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Helium atom

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5088: 4821: 3683: 546: 5083:{\displaystyle {\begin{aligned}&{\boldsymbol {\sigma }}_{0}^{1}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}0&1\\1&0\end{pmatrix}}={\frac {1}{\sqrt {2}}}(\uparrow \downarrow +\downarrow \uparrow )\;;\\&{\boldsymbol {\sigma }}_{1}^{1}={\begin{pmatrix}1&0\\0&0\end{pmatrix}}=\;\uparrow \uparrow \;;\;\;{\boldsymbol {\sigma }}_{-1}^{1}={\begin{pmatrix}0&0\\0&1\end{pmatrix}}=\;\downarrow \downarrow \;.\end{aligned}}} 10574: 847: 5367: 3408: 1930: 12377: 449: 9335: 34: 10277: 564: 6221: 1450: 5158: 7424: 12117: 12113: 4418: 1623: 9052: 3678:{\displaystyle {\begin{aligned}&|\chi _{s=1,m=0}\rangle ={\frac {1}{\sqrt {2}}}(|\uparrow \rangle |\downarrow \rangle +|\downarrow \rangle |\uparrow \rangle )\;;\\&|\chi _{s=1,m=1}\rangle =\;|\uparrow \rangle |\uparrow \rangle \;;\;\;|\chi _{s=1,m=-1}\rangle =\;|\downarrow \rangle |\downarrow \rangle \;.\end{aligned}}} 4781: 11051: 5995: 1224: 12379:
The first integral is said to be analogous to classical potential due to Coulomb interaction, where the squares of wavefunctions are interpreted as electron density. However, no such classical analog exists for the J term. Using Green's theorem, one can show that the J terms are always positive. From
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This is closer to the experimental value, but if a better trial wave function is used, an even more accurate answer could be obtained. An ideal wave function would be one that doesn't ignore the influence of the other electron. In other words, each electron represents a cloud of negative charge which
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Alternatively, a more generalized representation of the above can be provided without considering the spatial and spin parts separately. This method is useful in situations where such manipulation is not possible, however, it can be applied wherever needed. Since the spin part is tensor product of
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The wavefunction belongs to the tensor product of combined spin states and combined spatial wavefunctions, and since this Hamiltonian only acts on spatial wavefunctions, we can neglect spin states until after solving the spatial wavefunction. This is possible since, for any general vector, one has
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as per symmetrization and total spin number requirement. It is observed that triplet states are symmetric and singlet states are antisymmetric. Since the total wavefunction is antisymmetric, a symmetric spatial wavefunction can only be paired with antisymmetric wavefunction and vice versa. Hence
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is a general combined spatial wavefunction. This energy, however, is not degenerate with multiplicity given by the dimension of the space of combined spin states because of a symmetrization postulate, which requires that physical solutions for identical fermions should be totally antisymmetric,
7221: 8888: 5537: 6445: 3309: 11606: 10569:{\displaystyle \langle H\rangle =8E_{1}+\langle V_{ee}\rangle =8E_{1}+\left({\frac {e^{2}}{4\pi \varepsilon _{0}}}\right)\left({\frac {8}{\pi a^{3}}}\right)^{2}\int {\frac {e^{-4(r_{1}+r_{2})/a}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}\,d^{3}\mathbf {r} _{1}\,d^{3}\mathbf {r} _{2}} 11891: 4334: 842:{\displaystyle H(\mathbf {r} _{1},\,\mathbf {r} _{2})=\sum _{i=1,2}\left(-{\frac {\hbar ^{2}}{2\mu }}\nabla _{r_{i}}^{2}-{\frac {Ze^{2}}{4\pi \varepsilon _{0}r_{i}}}\right)-{\frac {\hbar ^{2}}{M}}\nabla _{r_{1}}\cdot \nabla _{r_{2}}+{\frac {e^{2}}{4\pi \varepsilon _{0}r_{12}}}} 3783:
orthohelium (triplet state) has a symmetric spin wavefunction but an antisymmetric spatial wavefunction and parahelium (singlet state) has an antisymmetric spin wavefunction but a symmetric spatial wavefunction. Hence the type of wavefunction of each state is given above. The
5865: 5362:{\displaystyle \sigma _{x}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}1&0\\0&-1\end{pmatrix}},\quad \sigma _{y}={\frac {i}{\sqrt {2}}}{\begin{pmatrix}1&0\\0&1\end{pmatrix}},\quad \sigma _{z}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}0&1\\1&0\end{pmatrix}}.} 4668: 4628: 9574: 5403:
can be solved independently. This is identical to the previously discussed method of finding spatial wavefunction eigenstates independently of the spin states, here spatial wavefunctions of different spin states correspond to the different components of the matrix.
10901: 1925:{\displaystyle H|\Phi \rangle =\sum _{ij}c_{ij}H|\varphi _{i}\rangle |\chi _{j}\rangle =\sum _{ij}c_{ij}(H|\varphi _{i}\rangle )|\chi _{j}\rangle =E\sum _{ij}c_{ij}|\varphi _{i}\rangle |\chi _{j}\rangle =\sum _{ij}c_{ij}E|\varphi _{i}\rangle |\chi _{j}\rangle ,} 12372:{\displaystyle J=\int \int \psi _{100}(\mathbf {r} _{1})\psi _{nlm}(\mathbf {r} _{2}){\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}\psi _{nlm}^{\text{*}}(\mathbf {r} _{1})\psi _{100}^{\text{*}}(\mathbf {r} _{2})d^{3}\mathbf {r} _{1}d^{3}\mathbf {r} _{2}} 5628: 4064: 5980: 2356:
Since the Hamiltonian is independent of spin, it commutes with all spin operators. Since it is also rotationally invariant, the total x, y or z component of angular momentum operator also commutes with the Hamiltonian. From these commutation relations,
5740: 7143: 10273: 10068: 10886: 9918: 9330:{\displaystyle \Delta ^{(1)}=\int \int {\frac {Z^{6}}{\pi ^{2}a_{0}^{6}}}{\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}e^{-{\frac {2Z(r_{1}+r_{2})}{a_{0}}}}d^{3}\mathbf {r} _{1}d^{3}\mathbf {r} _{2}={\frac {5}{4}}{\frac {ke^{2}}{a_{0}}}} 3778: 11882:
has a minus symbol. Since due to the symmetrization postulate, the combined spatial wavefunctions differ on symmetric or antisymmetric nature, the J term is responsible for the splitting of energy levels between ortho and para helium states.
6549: 3401: 10581: 8636: 8662: 11418:. The variational approach has been refined to very high accuracy for a comprehensive regime of quantum states by G.W.F. Drake and co-workers as well as J.D. Morgan III, Jonathan Baker and Robert Hill using Hylleraas or Frankowski- 5418: 6280: 7561: 3193: 11391: 11441: 6840: 1546: 7896: 4274: 2756: 6533: 6216:{\displaystyle H=-{\frac {1}{2m}}\mathbf {p} _{1}^{2}-{\frac {1}{2m}}\mathbf {p} _{2}^{2}-{\frac {kZe^{2}}{\mathbf {r} _{1}}}-{\frac {kZe^{2}}{\mathbf {r} _{2}}}+{\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}.} 1445:{\displaystyle H=-{\frac {1}{2m}}\mathbf {p} _{1}^{2}-{\frac {1}{2m}}\mathbf {p} _{2}^{2}-{\frac {kZe^{2}}{\mathbf {r} _{1}}}-{\frac {kZe^{2}}{\mathbf {r} _{2}}}+{\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}.} 4422:
If the Hamiltonian had been spin dependent, we would not have been able to treat each these components independently as shown previously since the Hamiltonian need not act in the same manner for all four components.
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This shows that the other electron somewhat shields the nucleus reducing the effective charge from 2 to 1.69. This result matches with experimental results closely as well as the calculations of effective Z in
11681: 9047: 8969: 4524: 7419:{\displaystyle \psi _{\pm }^{(0)}(\mathbf {r} _{1}\,,\mathbf {r} _{2})={\frac {1}{\sqrt {2}}}(\psi _{a}(\mathbf {r} _{1})\psi _{b}(\mathbf {r} _{2})\pm \psi _{a}(\mathbf {r} _{2})\psi _{b}(\mathbf {r} _{1}))} 6907: 9399: 4136: 4826: 3413: 10091:
in this case, the screening constant is S = 0.30. For the ground state of helium, for the average shielding approximation, the screening effect of each electron on the other one is equivalent to about
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these, the diagram for energy level splitting can be roughly sketched. It also follows that for these states of helium, the energy of parallel spins cannot be more than that of antiparallel spins.
8160: 8121: 5153: 1073: 4529: 2323: 2200: 12108:{\displaystyle I=\int \int |\psi _{100}(\mathbf {r} _{1})|^{2}|\psi _{nlm}(\mathbf {r} _{2})|^{2}{\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}d^{3}\mathbf {r} _{1}d^{3}\mathbf {r} _{2}} 8643:
The Hartree–Fock method is used for a variety of atomic systems. However it is just an approximation, and there are more accurate and efficient methods used today to solve atomic systems. The "
10142: 9923: 4413:{\displaystyle {\boldsymbol {\psi }}={\begin{pmatrix}\psi _{\uparrow \uparrow }&\psi _{\uparrow \downarrow }\\\psi _{\downarrow \uparrow }&\psi _{\downarrow \downarrow }\end{pmatrix}}} 8316:
of each electrons cannot be made on one particle without affecting the other. This follows since the wavefunction is always a superposition of different states where each electron has unique
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are independent Coulomb field Hamiltonian of each electron. Since the unperturbed Hamiltonian is a sum of two independent Hamiltonians (i.e. are separable), the wavefunction must be of form
4458: 7657: 11168: 9759: 4327: 11308: 4175: 3687: 5547: 3313: 4776:{\displaystyle {\boldsymbol {\sigma }}_{0}^{0}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}0&1\\-1&0\end{pmatrix}}={\frac {1}{\sqrt {2}}}(\uparrow \downarrow -\downarrow \uparrow )} 3977: 9371: 895: 5874: 5389: 11800: 8436: 8375: 8314: 8253: 7891: 7830: 5637: 11046:{\displaystyle \langle H\rangle =2Z^{2}E_{1}+2(Z-2)\left({\frac {e^{2}}{4\pi \varepsilon _{0}}}\right)\left\langle {\frac {1}{r}}\right\rangle +\left\langle V_{ee}\right\rangle } 7464: 3173: 7036: 2931: 1581: 9618: 953: 924: 7213: 7178: 6977: 6942: 6271: 2270: 2235: 2147: 2112: 1616: 2508:
Other operators that commute with the Hamiltonian are the spatial exchange operator and the parity operator. However a good combination of mutually commuting operators are:
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The quantum mechanical description of the helium atom is of special interest, because it is the simplest multi-electron system and can be used to understand the concept of
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need not correspond to physical states of identical electrons as per the symmetrization postulate. Thus, to obtain physical solutions symmetrization of the wavefunctions
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of helium is known to fifteen digits. In Hartree–Fock theory, the electrons are assumed to move in a potential created by the nucleus and the other electrons.
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A good theoretical descriptions of helium including the perturbation term can be obtained within the Hartree–Fock and Thomas–Fermi approximations (see below).
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states). Since the spin exchange operator can be expressed in terms of dot product of spin vectors, eigenkets of spin exchange operators are also eigenkets of
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Baker, Jonathan D.; Freund, David E.; Hill, Robert Nyden; Morgan, John D. (1990-02-01). "Radius of convergence and analytic behavior of the 1/Z expansion".
7469: 6735:{\displaystyle H_{0}=-{\frac {1}{2m}}\mathbf {p} _{1}^{2}-{\frac {1}{2m}}\mathbf {p} _{2}^{2}-{\frac {kZe^{2}}{r_{1}}}-{\frac {kZe^{2}}{r_{2}}}=H_{1}+H_{2}} 10739:{\displaystyle \langle H\rangle =8E_{1}+{\frac {5}{4a}}\left({\frac {e^{2}}{4\pi \epsilon _{0}}}\right)=8E_{1}-{\frac {5}{2}}E_{1}=-109+34=-75{\text{ eV}}} 8077:{\textstyle \psi ^{(0)}(\mathbf {r} _{1},\mathbf {r} _{2})=\psi _{n_{1},\ell _{1},m_{1}}(\mathbf {r} _{1})\psi _{n_{2},\ell _{2},m_{2}}(\mathbf {r} _{2})} 4426:
The matrix can also be represented as a linear combination of any given basis of four orthogonal (in the vector-space of 2×2 matrices) constant matrices
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The minimum value of Z needs to be calculated, so taking a derivative with respect to Z and setting the equation to 0 will give the minimum value of Z:
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By using more complicated/accurate wave functions, the ground state energy of helium has been calculated closer and closer to the experimental value
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The energy that we obtained is too low because the repulsion term between the electrons was ignored, whose effect is to raise the energy levels. As
8883:{\displaystyle \psi _{0}(r_{1}\,,r_{2})=\psi _{1,0,0}(r_{1})\psi _{1,0,0}(r_{2})={\frac {Z^{3}}{\pi a_{0}^{3}}}e^{-{\frac {Z(r_{1}+r_{2})}{a_{0}}}}} 13144: 561:
of helium, considered as a three-body system of two electrons and a nucleus and after separating out the centre-of-mass motion, can be written as
5532:{\displaystyle {\boldsymbol {\psi }}_{ij}(\mathbf {r} _{1},\,\mathbf {r} _{2})=-{\boldsymbol {\psi }}_{ji}(\mathbf {r} _{2},\,\mathbf {r} _{1}).} 9620:
is small. The net effect of each electron on the motion of the other one is to screen somewhat the charge of the nucleus, so a simple guess for
6440:{\displaystyle H_{0}=-{\frac {1}{2m}}\mathbf {p} _{1}^{2}-{\frac {1}{2m}}\mathbf {p} _{2}^{2}-{\frac {kZe^{2}}{r_{1}}}-{\frac {kZe^{2}}{r_{2}}}} 11175: 3304:{\displaystyle |\chi _{s=0,m=0}\rangle ={\frac {1}{\sqrt {2}}}(|\uparrow \rangle |\downarrow \rangle -|\downarrow \rangle |\uparrow \rangle )} 12540: 1151: 11601:{\displaystyle H_{0}=-{\frac {1}{2}}\nabla _{r_{1}}^{2}-{\frac {1}{2}}\nabla _{r_{2}}^{2}-{\frac {kZe^{2}}{r_{1}}}-{\frac {kZe^{2}}{r_{2}}}} 12905:
J.D. Baker, R.N. Hill, and J.D. Morgan III (1989), "High Precision Calculation of Helium Atom Energy Levels", in AIP ConferenceProceedings
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G.W.F. Drake (2006). "Springer Handbook of Atomic, molecular, and Optical Physics", Edited by G.W.F. Drake (Springer, New York), 199-219.
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Since ground state corresponds to (1,0,0) state, there can only be one representation of such wavefunction whose spatial wavefunction is:
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Note that all wavefunction obtained thus far cannot be separated into wavefunctions of each particle (even for electrons with identical
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is the combined spin component. The Hamiltonian operator, since it only acts on the spatial component, gives the eigenvector equation:
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fold degenerate. For electrons, the total spin can have values of 0 or 1. A state with the quantum numbers: principal quantum number
12812:
Yan, Zong-Chao; Drake, G. W. F. (1995-06-12). "High Precision Calculation of Fine Structure Splittings in Helium and He-Like Ions".
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will influence the type of wavefunction required by symmetrization postulate which would in turn influence the energy of the state.
11092: 5860:{\displaystyle {\boldsymbol {\phi }}_{m}=\psi _{-}(\mathbf {r} _{1},\,\mathbf {r} _{2}){\boldsymbol {\sigma }}_{m}^{1},\;m=-1,0,1} 11274: 9756:
is the effective charge. The potential is a Coulomb interaction, so the corresponding individual electron energies are given by
958: 7699: 4623:{\textstyle {\boldsymbol {\psi }}=\sum _{ik}\phi _{i}^{k}(\mathbf {r} _{1},\,\mathbf {r} _{2}){\boldsymbol {\sigma }}_{k}^{i}} 1937: 12691: 12585: 8126: 8087: 13158:
D. Z. Kandula; C. Gohle; T. J. Pinkert; W. Ubachs; K. S. E. Eikema (2010). "Extreme Ultraviolet Frequency Comb Metrology".
5099: 1027: 11760: 9384:. A better approximation for ground state energy is obtained by choosing better trial wavefunction in variational method. 8194:) i.e. the wavefunctions are always in superposition of some kind. In other words, one cannot completely determine states 2275: 2152: 2485:, this would only be true in the absence of symmetrization postulate. Due to the symmetrization postulate, the choice of 9569:{\displaystyle {\bar {H'}}={\frac {ke^{2}}{r_{12}}}-{\frac {kZe^{2}}{r_{1}}}-V(r_{1})-{\frac {kZe^{2}}{r_{2}}}-V(r_{2})} 13106: 457: 13026:"Energies and relativistic corrections for the Rydberg states of helium: Variational results and asymptotic analysis" 12633: 5092:
It is easy to show, that the singlet state is invariant under all rotations (a scalar entity), while the triplet are
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gets bigger, our approach should yield better results, since the electron-electron repulsion term will get smaller.
5623:{\displaystyle {\boldsymbol {\phi }}=\psi _{+}(\mathbf {r} _{1},\,\mathbf {r} _{2}){\boldsymbol {\sigma }}_{0}^{0}} 4279: 469: 6226: 4141: 4059:{\displaystyle |\uparrow \rangle _{1}|\downarrow \rangle _{2}\neq |\downarrow \rangle _{1}|\uparrow \rangle _{2}} 558: 537:
in 1927. Its success was considered to be one of the earliest signs of validity of Schrödinger's wave mechanics.
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Following from the above approximation, effectively reducing three body problem to two body problem, we have:
5975:{\displaystyle \psi _{-}(\mathbf {r} _{1},\,\mathbf {r} _{2})=-\psi _{-}(\mathbf {r} _{2},\,\mathbf {r} _{1})} 10077:
was 1.70, that would make the expression above for the ground state energy agree with the experimental value
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The proper wave function then must be composed of the symmetric (+) and antisymmetric(−) linear combinations:
5735:{\displaystyle \psi _{+}(\mathbf {r} _{1},\,\mathbf {r} _{2})=\psi _{+}(\mathbf {r} _{2},\,\mathbf {r} _{1})} 4177:
describe the spin projection of both electrons in this coordinate system. The usual normalization condition,
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Schematic termscheme for Para- and Orthohelium with one electron in ground state 1s and one excited electron.
50: 9342: 7138:{\textstyle \psi (\mathbf {r} _{1},\mathbf {r} _{2})=\psi _{a}(\mathbf {r} _{1})\psi _{b}(\mathbf {r} _{2})} 5093: 854: 12414:. This value was measured experimentally. The theoretic value of Helium atom's second ionization energy is 5372: 258: 10268:{\displaystyle \psi _{0}(\mathbf {r} _{1},\,\mathbf {r} _{2})={\frac {8}{\pi a^{3}}}e^{-2(r_{1}+r_{2})/a}} 10063:{\displaystyle \psi _{0}(r_{1}\,,r_{2})={\sqrt {\frac {Z_{e}^{3}}{\pi a_{0}^{3}}}}e^{-Z_{e}(r_{1}+r_{2})}} 12477: 8319: 8258: 8197: 7835: 7774: 7429: 3119: 10881:{\displaystyle \psi (\mathbf {r} _{1},\mathbf {r} _{2})={\frac {Z^{3}}{\pi a^{3}}}e^{-Z(r_{1}+r_{2})/a}} 2876: 1551: 12607: 929: 900: 12389: 9913:{\displaystyle E_{0}=-{\frac {k(Z-S)^{2}e^{2}}{2a_{0}n^{2}}}=-{\frac {kZ_{e}^{2}e^{2}}{2a_{0}n^{2}}}} 8378: 5408: 5396: 209: 153: 7183: 7148: 6947: 6912: 3773:{\displaystyle \psi (\mathbf {r} _{1},\mathbf {r} _{2})=-\psi (\mathbf {r} _{2}\,,\mathbf {r} _{1})} 2240: 2205: 2117: 2082: 1586: 3396:{\displaystyle \psi (\mathbf {r} _{1},\mathbf {r} _{2})=\psi (\mathbf {r} _{2}\,,\mathbf {r} _{1})} 2936: 203: 10749:
somewhat shields the nucleus so that the other electron actually sees an effective nuclear charge
13229: 12909:, Relativistic, Quantum Electrodynamic, and Weak Interaction Effects in Atoms (AIP, New York),123 12532: 11427: 9589: 8165: 522: 11058: 10094: 7662: 7569: 5400: 2465:. Although the purely spatial form of the Hamiltonian implies that the energy is independent of 2328: 518: 12482: 11852: 11819: 8387: 3848:
spin Hilbert vector spaces, its basis can be represented by tensor product of each of the set,
1099: 514: 389: 2763: 12653:(in German). Vol. Bd. III (Quantenmechanik). Berlin: Akademie-Verlag. Kap. IX, pp. 218. 10127: 8647:" for helium and other few electron systems can be solved quite accurately. For example, the 8631:{\displaystyle E_{n_{1},n_{2}}^{(0)}=E_{n_{1}}+E_{n_{2}}=-{\frac {kZ^{2}e^{2}}{2a_{0}}}\left} 498: 12769:
Drake, G.W.F.; Van, Zong-Chao (1994). "Variational eigenvalues for the S states of helium".
1125: 13177: 13037: 12988: 12928: 12872: 12821: 12778: 12497: 554: 267: 142: 102: 11816:. If the combined spatial wavefunction is symmetric, its energy level has the + symbol in 8974:
We can find the first order correction in energy due to electron repulsion in Hamiltonian
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because then, the spin of the electrons are in a superposition of different spin states:
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This article is about the physics of atomic helium. For other properties of helium, see
13201: 13167: 13069: 12472: 11423: 7009: 6982: 2856: 2836: 2816: 2592: 2565: 2538: 2511: 2441: 2414: 1079: 1022:. It is important to note that it operates not in normal space, but in a 6-dimensional 502: 12884: 7556:{\displaystyle \psi _{+}^{(0)}=\psi _{a}(\mathbf {r} _{1})\psi _{a}(\mathbf {r} _{2})} 534: 13193: 13138: 13102: 13061: 13053: 12952: 12944: 12888: 12845: 12837: 12794: 12790: 12687: 12654: 12629: 12581: 12502: 12400: 8644: 5391:
in the above (scalar) Hamiltonian are neglected (e.g. an external magnetic field, or
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for the helium atom has not been found. However, various approximations, such as the
494: 13073: 11386:{\displaystyle {\frac {1}{2}}\left({\frac {3}{2}}\right)^{6}E_{1}=-77.5{\text{ eV}}} 13205: 13189: 13185: 13045: 13004: 12996: 12936: 12880: 12829: 12786: 12721: 12713: 12679: 12573: 11419: 11314: 6835:{\displaystyle H_{i}=-{\frac {1}{2m}}\mathbf {p} _{i}^{2}-{\frac {kZe^{2}}{r_{i}}}} 2488: 2468: 1541:{\textstyle |\Phi \rangle =\sum _{ij}c_{ij}|\varphi _{i}\rangle |\chi _{j}\rangle } 429: 336: 13124: 533:
of the atom. Historically, the first such helium spectrum calculation was done by
231: 13234: 12979: 11812: 172: 12833: 12512: 4269:{\textstyle \sum _{ij}\int d\mathbf {r} _{1}d\mathbf {r} _{2}|\psi _{ij}|^{2}=1} 13224: 13000: 12673: 12507: 4067: 2411:
also commutes with the Hamiltonian which implies that energy is independent of
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is a central potential which is chosen so that the effect of the perturbation
2751:{\displaystyle H|N,L,m_{l},S,m_{s}\rangle =E_{nls}|N,L,m_{l},S,m_{s}\rangle ,} 501:
to a nucleus containing two protons along with two neutrons, depending on the
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corrections to get full agreement with experiment to spectroscopic accuracy.
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A convenient basis consists of one anti-symmetric matrix (with total spin
13009: 3175:. Hence parahelium can also be said to be the spin anti-symmetric state ( 1219:
disappears, so that in operator language, the Hamiltonian simplifies to:
9734:{\displaystyle V(r)=-{\frac {k(Z-S)e^{2}}{r}}=-{\frac {kZ_{e}e^{2}}{r}}} 6528:{\displaystyle H'={\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}} 1212:{\textstyle {\frac {\hbar ^{2}}{M}}\nabla _{r_{1}}\cdot \nabla _{r_{2}}} 12628:(in German). VEB Bibliographisches Institut Leipzig. pp. 192–194. 349: 154: 133: 13101:. Vol. I. McGraw-Hill Book Company, Inc. 1960. pp. 486–487. 3818:
degeneracy solely comes from this spatial wavefunction. Note that for
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is 2 for helium. In the approximation of an infinitely heavy nucleus,
3967:{\displaystyle \{|\uparrow \rangle _{2}\,,|\downarrow \rangle _{2}\}} 3904:{\displaystyle \{|\uparrow \rangle _{1}\,,|\downarrow \rangle _{1}\}} 545: 278: 12970:
Scott, T. C.; Lüchow, A.; Bressanini, D.; Morgan, J. D. III (2007).
12725: 2071:{\textstyle |\psi _{j}\rangle =\sum _{i}c_{ij}|\varphi _{i}\rangle } 439:
Except where otherwise noted, data are given for materials in their
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In general, for (1s)(nl) state, in first order perturbation theory:
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We note that the ground state energy of unperturbed helium atom as:
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for helium with two electrons can be written as a sum of two terms:
510: 192: 13172: 12863:
Drake, G. W. F. (1999). "High Precision Theory of Atomic Helium".
11676:{\textstyle {\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}} 9042:{\textstyle {\frac {ke^{2}}{|\mathbf {r} _{1}-\mathbf {r} _{2}|}}} 8964:{\displaystyle E_{0}=-4{\frac {ke^{2}}{a_{0}}}=-108.8{\text{ eV}}} 7466:(both electrons have identical quantum numbers, parahelium only): 5411:, which for fermions (like electrons) requires antisymmetry under 4519:{\displaystyle \phi _{i}^{k}(\mathbf {r} _{1},\,\mathbf {r} _{2})} 101: 10121: 218: 6902:{\textstyle |\psi \rangle =|\psi _{1}\rangle |\psi _{2}\rangle } 5369:
Since all spin interaction terms between the four components of
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is the reduced mass of an electron with respect to the nucleus,
11849:, whereas for the antisymmetric combined spatial wavefunction, 10753:
that is less than 2. A wave function of this type is given by:
4131:{\displaystyle \psi _{ij}(\mathbf {r} _{1},\,\mathbf {r} _{2})} 4071: 490: 20: 8654: 10898:. The Hamiltonian using the wave function above is given by: 9339:
The energy for ground state of helium in first order becomes
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but are in fact orthogonal. In the considered approximation (
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Kramida, A.; Ralchenko, Yu.; Reader, J., and NIST ASD Team.
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List of quantum-mechanical systems with analytical solutions
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respectively. However, the spatial wavefunction of the form
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elements. This general spinor can be written as 2×2 matrix:
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Consider the same setting where unperturbed Hamiltonian is:
486: 183: 12623: 12394: 10084:= −2.903 a.u. of the ground state energy of helium. Since 4070:), the wave function can be represented as a second order 1015:{\displaystyle r_{12}=|\mathbf {r} _{1}-\mathbf {r} _{2}|} 7761:{\displaystyle \psi _{a}=\psi _{1s},\psi _{b}=\psi _{2s}} 11265:{\displaystyle {\frac {d}{dZ}}\left(\leftE_{1}\right)=0} 9920:
and the corresponding spatial wave function is given by
1992:{\displaystyle H|\psi _{j}\rangle =E|\psi _{j}\rangle ,} 13127:"NIST Atomic Spectra Database Ionization Energies Data" 33: 12425:. The total ground state energy of the helium atom is 11855: 11822: 11614: 11061: 10097: 9345: 8980: 8390: 8322: 8261: 8200: 8168: 8155:{\displaystyle |\downarrow \rangle |\uparrow \rangle } 8116:{\displaystyle |\uparrow \rangle |\downarrow \rangle } 7899: 7838: 7777: 7186: 7151: 7039: 7012: 6985: 6950: 6915: 6848: 5325: 5260: 5192: 5034: 4962: 4867: 4709: 4532: 4351: 4183: 3824: 3789: 3087: 3020: 2766: 2595: 2568: 2541: 2514: 2491: 2471: 2444: 2417: 2390: 2363: 2331: 2243: 2208: 2120: 2085: 2005: 1589: 1554: 1461: 1154: 12918: 12120: 11894: 11763: 11692: 11444: 11323: 11277: 11178: 11095: 10904: 10759: 10584: 10280: 10145: 9926: 9762: 9637: 9592: 9402: 9055: 8898: 8665: 8439: 8255:
of particle 1 and 2, or measurements of all details,
8129: 8090: 7702: 7665: 7609: 7572: 7472: 7432: 7224: 6748: 6552: 6455: 6283: 6235: 5998: 5877: 5752: 5640: 5550: 5421: 5375: 5161: 5148:{\displaystyle (\sigma _{x},\sigma _{y},\sigma _{z})} 5102: 4824: 4790: 4671: 4639: 4466: 4432: 4337: 4282: 4144: 4080: 3980: 3917: 3854: 3690: 3411: 3316: 3196: 3122: 3055: 2988: 2939: 2879: 2859: 2839: 2819: 2624: 2278: 2155: 1940: 1626: 1227: 1128: 1102: 1082: 1068:{\displaystyle (\mathbf {r} _{1},\,\mathbf {r} _{2})} 1030: 961: 932: 903: 857: 567: 6546:
is just the sum of the two hydrogenic Hamiltonians:
2318:{\displaystyle |\psi _{i}\rangle |\chi _{i}\rangle } 2195:{\displaystyle |\psi _{i}\rangle |\chi _{i}\rangle } 12624:Rennert, P.; Schmiedel, H.; Weißmantel, C. (1988). 12972:"The Nodal Surfaces of Helium Atom Eigenfunctions" 12820:(24). American Physical Society (APS): 4791–4794. 12712:Kramida, Alexander; Ralchenko, Yuri (2009-07-21). 12371: 12107: 11874: 11841: 11794: 11749: 11675: 11600: 11385: 11302: 11264: 11162: 11089:the expectation value of the Hamiltonian becomes: 11074: 11045: 10880: 10738: 10568: 10267: 10130:can be applied to the electron-electron potential 10110: 10062: 9912: 9733: 9612: 9568: 9365: 9329: 9041: 8963: 8882: 8630: 8422: 8369: 8308: 8247: 8186: 8154: 8115: 8076: 7885: 7824: 7760: 7688: 7651: 7595: 7555: 7458: 7418: 7207: 7172: 7137: 7025: 6998: 6971: 6936: 6901: 6834: 6734: 6527: 6439: 6265: 6215: 5974: 5859: 5734: 5622: 5531: 5383: 5361: 5147: 5082: 4802: 4775: 4651: 4622: 4518: 4452: 4412: 4321: 4268: 4169: 4130: 4058: 3966: 3903: 3844:, there is no degeneracy in spatial wavefunction. 3836: 3810: 3772: 3677: 3395: 3303: 3167: 3108: 3067: 3041: 3000: 2971: 2925: 2865: 2845: 2825: 2805: 2750: 2608: 2581: 2554: 2527: 2497: 2477: 2457: 2430: 2403: 2376: 2345: 2317: 2264: 2229: 2194: 2141: 2106: 2070: 1991: 1924: 1610: 1575: 1540: 1444: 1211: 1140: 1114: 1088: 1067: 1014: 947: 918: 889: 841: 13036:(5). American Physical Society (APS): 2378–2409. 12927:(3). American Physical Society (APS): 1247–1273. 12565: 11433: 11317:. Hence, we obtain the most accurate result yet: 1934:which implies that one should find solutions for 13216: 12711: 12572:. Cambridge University Press. pp. 455–459. 12383: 6275:where the zero-order unperturbed Hamiltonian is 2237:is the energy eigenket spatial wavefunction and 230: 12648: 11750:{\displaystyle E=E_{100}+E_{nlm}+\Delta ^{(1)}} 5415:(totally antisymmetric wavefunction condition) 5407:The spin here only comes into play through the 4453:{\displaystyle {\boldsymbol {\sigma }}_{k}^{i}} 77: 13024:Drake, G. W. F.; Yan, Zong-Chao (1992-09-01). 12566:Sakurai, J. J.; Napolitano, Jim (2017-09-21). 11404:represents the ionization energy of hydrogen. 10122:Ground state of Helium: The variational method 7652:{\displaystyle \psi _{a}=\psi _{b}=\psi _{1s}} 4784:and three symmetric matrices (with total spin 955:are the electron-nucleus distance vectors and 12541:National Center for Biotechnology Information 5413:simultaneous exchange of spin and coordinates 3181:) or orthohelium to be spin symmetric state ( 2353:is merely some superpostion of these states. 13143:: CS1 maint: multiple names: authors list ( 12738: 11163:{\displaystyle \langle H\rangle =\leftE_{1}} 11102: 11096: 10911: 10905: 10591: 10585: 10325: 10309: 10287: 10281: 8971:Which is 30% larger than experimental data. 8149: 8138: 8110: 8099: 7202: 7167: 6966: 6931: 6896: 6878: 6857: 5096:representations of an ordinary space vector 4322:{\displaystyle |i\rangle _{1}|j\rangle _{2}} 4310: 4292: 4047: 4029: 4008: 3990: 3961: 3952: 3930: 3918: 3898: 3889: 3867: 3855: 3664: 3653: 3638: 3593: 3582: 3567: 3517: 3506: 3492: 3481: 3452: 3295: 3284: 3270: 3259: 3230: 2742: 2674: 2340: 2312: 2294: 2259: 2224: 2189: 2171: 2136: 2101: 2065: 2021: 1983: 1959: 1916: 1898: 1848: 1830: 1780: 1759: 1706: 1688: 1638: 1605: 1570: 1535: 1517: 1470: 378:−269 °C (−452.20 °F; 4.15 K) 12533:"Helium - PubChem Public Chemical Database" 11303:{\displaystyle Z={\frac {27}{16}}\sim 1.69} 11055:After calculating the expectation value of 8655:Ground state of Helium: Perturbation method 8384:We can infer from these wavefunctions that 4170:{\displaystyle i,j=\,\uparrow ,\downarrow } 5832: 5072: 5068: 5005: 5004: 5000: 4996: 4928: 3667: 3644: 3601: 3600: 3596: 3573: 3523: 2616:. Hence the final solutions are given as: 141: 13171: 13008: 12753: 10543: 10520: 10174: 9950: 9747:is a screening constant and the quantity 8689: 8350: 8336: 8329: 8289: 8275: 8268: 8228: 8214: 8207: 7866: 7852: 7805: 7791: 7261: 5956: 5906: 5796: 5716: 5669: 5587: 5510: 5455: 4587: 4500: 4157: 4112: 3939: 3876: 3751: 3374: 1049: 589: 266: 13120: 13118: 13023: 12811: 12768: 12649:Landau, L. D.; Lifschitz, E. M. (1971). 11608:and perturbation is electron repulsion: 5985: 4276:, follows from the orthogonality of all 2079:imposing a restriction on the choice of 544: 12671: 12395:Experimental value of ionization energy 10894:as a variational parameter to minimize 10578:After integrating this, the result is: 9366:{\textstyle E\approx -74.8{\text{ eV}}} 5814: 5755: 5605: 5552: 5479: 5424: 5377: 5008: 4939: 4832: 4674: 4605: 4534: 4435: 4339: 2149:. Hence the solutions are of the form: 1583:is a combined spatial wavefunction and 208: 13217: 12605: 11422:basis functions. One needs to include 9373:compared to its experimental value of 7659:) for orthohelium, where consequently 6537:is the electron-electron interaction. 890:{\displaystyle \mu ={\frac {mM}{m+M}}} 13115: 12862: 12758:(Second ed.). Pearson Education. 10126:To obtain a more accurate energy the 5384:{\displaystyle {\boldsymbol {\psi }}} 303:Key: SWQJXJOGLNCZEY-UHFFFAOYSA-N 121: 12707: 12705: 12703: 12601: 12599: 12597: 12561: 12559: 11795:{\displaystyle \Delta ^{(1)}=I\pm J} 8370:{\textstyle (n\,,l\,,m_{l}\,,m_{s})} 8309:{\textstyle (n\,,l\,,m_{l}\,,m_{s})} 8248:{\textstyle (n\,,l\,,m_{l}\,,m_{s})} 7886:{\textstyle (n_{2}\,,l_{2}\,,m_{2})} 7825:{\textstyle (n_{1}\,,l_{1}\,,m_{1})} 428: 9387: 7459:{\displaystyle \psi _{a}=\psi _{b}} 3168:{\displaystyle S=(S_{1}+S_{2})^{2}} 221: 191: 13: 13099:Quantum Theory of Atomic Structure 13091: 12743:(2nd ed.). Pearson Education. 11857: 11824: 11765: 11732: 11507: 11472: 9057: 7768:) is the metastable ground state. 4460:with scalar function coefficients 2926:{\displaystyle J=|L-S|,\dots ,L+S} 2337: 1635: 1576:{\textstyle |\varphi _{i}\rangle } 1467: 1193: 1173: 1109: 778: 758: 661: 14: 13246: 12885:10.1238/physica.topical.083a00083 12756:Introduction to Quantum Mechanics 12739:Bransden, B. H.; Joachain, C. J. 12700: 12651:Lehrbuch der Theoretischen Physik 12594: 12556: 12553:Unsöld, Ann. Phys., 82 (1927) 355 7566:This explains the absence of the 2272:is a spin wavefunction such that 12359: 12337: 12312: 12279: 12235: 12220: 12182: 12148: 12095: 12073: 12043: 12028: 11978: 11927: 11655: 11640: 10783: 10768: 10556: 10533: 10502: 10487: 10177: 10161: 9275: 9253: 9162: 9147: 9021: 9006: 8061: 8000: 7936: 7921: 7540: 7512: 7400: 7372: 7341: 7313: 7267: 7251: 7122: 7094: 7063: 7048: 6782: 6621: 6586: 6507: 6492: 6352: 6317: 6192: 6177: 6137: 6100: 6060: 6025: 5959: 5943: 5909: 5893: 5799: 5783: 5719: 5703: 5672: 5656: 5590: 5574: 5513: 5497: 5458: 5442: 4590: 4574: 4503: 4487: 4220: 4205: 4115: 4099: 3757: 3741: 3714: 3699: 3405:and triplet states are given as: 3380: 3364: 3340: 3325: 1421: 1406: 1366: 1329: 1289: 1254: 1052: 1036: 997: 982: 948:{\displaystyle \mathbf {r} _{2}} 935: 919:{\displaystyle \mathbf {r} _{1}} 906: 592: 576: 447: 32: 13151: 13080: 13017: 12963: 12912: 12899: 12856: 12805: 12762: 12747: 12675:Principles of Quantum Mechanics 8433:The corresponding energies are: 7208:{\textstyle |\psi _{2}\rangle } 7173:{\textstyle |\psi _{1}\rangle } 6972:{\textstyle |\psi _{2}\rangle } 6937:{\textstyle |\psi _{1}\rangle } 5294: 5229: 2265:{\textstyle |\chi _{i}\rangle } 2230:{\textstyle |\psi _{i}\rangle } 2142:{\textstyle |\psi _{i}\rangle } 2107:{\textstyle |\chi _{i}\rangle } 1611:{\textstyle |\chi _{i}\rangle } 1148:and the mass polarization term 540: 443:(at 25 °C , 100 kPa). 13190:10.1103/PhysRevLett.105.063001 12741:Physics of Atoms and Molecules 12732: 12665: 12642: 12617: 12547: 12525: 12322: 12307: 12289: 12274: 12246: 12214: 12192: 12177: 12158: 12143: 12054: 12022: 11993: 11988: 11973: 11953: 11942: 11937: 11922: 11908: 11867: 11861: 11834: 11828: 11775: 11769: 11742: 11736: 11666: 11634: 11434:Perturbation theory for Helium 10958: 10946: 10865: 10839: 10793: 10763: 10513: 10481: 10466: 10440: 10252: 10226: 10187: 10156: 10055: 10029: 9964: 9937: 9798: 9785: 9674: 9662: 9647: 9641: 9604: 9563: 9550: 9506: 9493: 9414: 9223: 9197: 9173: 9141: 9067: 9061: 9032: 9000: 8862: 8836: 8782: 8769: 8744: 8731: 8703: 8676: 8476: 8470: 8364: 8323: 8303: 8262: 8242: 8201: 8146: 8142: 8135: 8131: 8107: 8103: 8096: 8092: 8071: 8056: 8010: 7995: 7946: 7916: 7911: 7905: 7880: 7839: 7819: 7778: 7550: 7535: 7522: 7507: 7489: 7483: 7413: 7410: 7395: 7382: 7367: 7351: 7336: 7323: 7308: 7295: 7277: 7246: 7241: 7235: 7188: 7153: 7132: 7117: 7104: 7089: 7073: 7043: 6952: 6917: 6882: 6864: 6850: 6518: 6486: 6203: 6171: 5969: 5938: 5919: 5888: 5809: 5778: 5729: 5698: 5682: 5651: 5600: 5569: 5523: 5492: 5468: 5437: 5142: 5103: 5069: 4997: 4925: 4922: 4916: 4913: 4770: 4767: 4761: 4758: 4600: 4569: 4513: 4482: 4397: 4385: 4371: 4359: 4302: 4284: 4250: 4231: 4164: 4158: 4125: 4094: 4043: 4039: 4025: 4021: 4004: 4000: 3986: 3982: 3948: 3944: 3926: 3922: 3885: 3881: 3863: 3859: 3805: 3790: 3767: 3736: 3724: 3694: 3661: 3657: 3650: 3646: 3603: 3590: 3586: 3579: 3575: 3535: 3520: 3514: 3510: 3503: 3499: 3489: 3485: 3478: 3474: 3470: 3420: 3390: 3359: 3350: 3320: 3298: 3292: 3288: 3281: 3277: 3267: 3263: 3256: 3252: 3248: 3198: 3190:The singlet state is given as: 3156: 3129: 2901: 2887: 2800: 2785: 2782: 2767: 2697: 2629: 2333: 2298: 2280: 2245: 2210: 2175: 2157: 2122: 2087: 2051: 2007: 1969: 1945: 1902: 1884: 1834: 1816: 1766: 1762: 1745: 1738: 1692: 1674: 1631: 1591: 1556: 1521: 1503: 1463: 1432: 1400: 1062: 1031: 1008: 976: 602: 571: 525:, can be used to estimate the 342: 1: 12777:(4–5). Elsevier BV: 486–490. 12519: 12384:First excited state of Helium 5155:, with the three components: 2972:{\displaystyle n^{2S+1}L_{J}} 12871:(1). IOP Publishing: 83–92. 12791:10.1016/0009-2614(94)01085-4 12754:Griffiths, David I. (2005). 12513:"Helium atom" on Wikiversity 8377:. This is in agreement with 8187:{\textstyle \sigma _{0}^{0}} 7426:or for the special cases of 6449:while the perturbation term: 7: 12834:10.1103/physrevlett.74.4791 12465: 11075:{\textstyle {\frac {1}{r}}} 10111:{\textstyle {\frac {1}{3}}} 9613:{\displaystyle {\bar {H'}}} 3081:, so called as there exist 3014:, so called as there exist 2873:and total angular momentum 2346:{\textstyle |\Phi \rangle } 10: 13251: 13001:10.1103/PhysRevA.75.060101 12626:Kleine Enzyklopädie Physik 12387: 11875:{\textstyle \Delta ^{(1)}} 11842:{\textstyle \Delta ^{(1)}} 8423:{\textstyle E=E_{a}+E_{b}} 7689:{\displaystyle 2^{3}S_{1}} 7596:{\displaystyle 1^{3}S_{1}} 6266:{\displaystyle H=H_{0}+H'} 5544:is then the singlet state 18: 12714:"Atomic Spectra Database" 12684:10.1007/978-1-4757-0576-8 12390:Fermi heap and Fermi hole 8379:Pauli exclusion principle 5409:Pauli exclusion principle 5397:angular momentum coupling 3075:are called orthohelium ( 3008:, are called parahelium ( 2853:, angular quantum number 2806:{\textstyle (2l+1)(2s+1)} 1115:{\displaystyle M=\infty } 437: 411: 382: 329: 312: 287: 61: 49: 44: 31: 13050:10.1103/physreva.46.2378 12941:10.1103/physreva.41.1247 12771:Chemical Physics Letters 12569:Modern Quantum Mechanics 11886:They are calculated as: 10139:using the wave function 10118:of the electric charge. 2982:States corresponding to 493:. Helium is composed of 489:of the chemical element 407:126.151-126.155 J K mol 12814:Physical Review Letters 12478:Araki–Sucher correction 5094:spherical vector tensor 505:, held together by the 12483:Hydrogen molecular ion 12373: 12109: 11876: 11843: 11796: 11751: 11677: 11602: 11428:quantum electrodynamic 11387: 11304: 11266: 11164: 11076: 11047: 10882: 10740: 10570: 10269: 10112: 10064: 9914: 9735: 9614: 9570: 9367: 9331: 9043: 8965: 8884: 8632: 8424: 8371: 8310: 8249: 8188: 8156: 8117: 8078: 7893:where wavefunction is 7887: 7826: 7762: 7690: 7653: 7597: 7557: 7460: 7420: 7209: 7174: 7139: 7027: 7000: 6973: 6938: 6903: 6836: 6736: 6529: 6441: 6267: 6217: 5976: 5861: 5736: 5624: 5533: 5385: 5363: 5149: 5084: 4804: 4777: 4653: 4624: 4520: 4454: 4414: 4323: 4270: 4171: 4132: 4060: 3968: 3911:with each of the set, 3905: 3838: 3812: 3774: 3679: 3397: 3305: 3169: 3110: 3069: 3043: 3002: 2973: 2927: 2867: 2847: 2827: 2807: 2752: 2610: 2583: 2556: 2529: 2499: 2479: 2459: 2432: 2405: 2378: 2347: 2319: 2266: 2231: 2196: 2143: 2108: 2072: 1993: 1926: 1612: 1577: 1542: 1446: 1213: 1142: 1141:{\displaystyle \mu =m} 1116: 1090: 1076:. The nuclear charge, 1069: 1016: 949: 920: 891: 843: 550: 12578:10.1017/9781108499996 12374: 12110: 11877: 11844: 11797: 11752: 11678: 11603: 11388: 11305: 11267: 11165: 11077: 11048: 10883: 10741: 10571: 10270: 10128:variational principle 10113: 10065: 9915: 9736: 9615: 9571: 9368: 9332: 9044: 8966: 8885: 8633: 8425: 8372: 8311: 8250: 8189: 8157: 8118: 8079: 7888: 7827: 7763: 7691: 7654: 7598: 7558: 7461: 7421: 7210: 7175: 7140: 7028: 7001: 6974: 6939: 6904: 6837: 6737: 6530: 6442: 6268: 6218: 5986:Approximation methods 5977: 5862: 5746:is the triplet state 5737: 5625: 5534: 5401:Schrödinger equations 5386: 5364: 5150: 5085: 4810:, corresponding to a 4805: 4778: 4659:, corresponding to a 4654: 4625: 4521: 4455: 4415: 4324: 4271: 4172: 4133: 4061: 3969: 3906: 3839: 3813: 3775: 3680: 3398: 3306: 3170: 3111: 3070: 3044: 3003: 2974: 2928: 2868: 2848: 2828: 2808: 2753: 2611: 2584: 2557: 2530: 2500: 2480: 2460: 2433: 2406: 2404:{\textstyle L_{\pm }} 2379: 2377:{\textstyle S_{\pm }} 2348: 2325:is antisymmetric and 2320: 2267: 2232: 2197: 2144: 2109: 2073: 1994: 1927: 1613: 1578: 1543: 1447: 1214: 1143: 1117: 1091: 1070: 1017: 950: 921: 892: 844: 548: 499:electromagnetic force 51:Systematic IUPAC name 13129:. Gaithersburg, MD: 12672:Shankar, R. (1994). 12606:Littlejohn, Robert. 12498:Quantum field theory 12118: 11892: 11853: 11820: 11802:where I is known as 11761: 11690: 11612: 11442: 11321: 11275: 11176: 11093: 11059: 10902: 10757: 10582: 10278: 10143: 10095: 9924: 9760: 9635: 9590: 9400: 9343: 9053: 8978: 8896: 8663: 8437: 8388: 8320: 8259: 8198: 8166: 8127: 8088: 7897: 7836: 7775: 7700: 7663: 7607: 7570: 7470: 7430: 7222: 7184: 7149: 7037: 7010: 6983: 6948: 6913: 6846: 6746: 6550: 6453: 6281: 6233: 5996: 5875: 5750: 5638: 5548: 5419: 5393:relativistic effects 5373: 5159: 5100: 4822: 4788: 4669: 4637: 4530: 4464: 4430: 4335: 4280: 4181: 4142: 4138:, where the indices 4078: 3978: 3915: 3852: 3822: 3787: 3688: 3409: 3314: 3194: 3120: 3085: 3053: 3018: 2986: 2937: 2877: 2857: 2837: 2817: 2764: 2760:where the energy is 2622: 2593: 2566: 2539: 2512: 2489: 2469: 2442: 2415: 2388: 2361: 2329: 2276: 2241: 2206: 2153: 2118: 2083: 2003: 1938: 1624: 1587: 1552: 1459: 1225: 1152: 1126: 1100: 1080: 1028: 1024:configuration space 959: 930: 901: 855: 565: 555:quantum entanglement 519:Schrödinger equation 515:closed-form solution 13182:2010PhRvL.105f3001K 13042:1992PhRvA..46.2378D 12993:2007PhRvA..75f0101S 12933:1990PhRvA..41.1247B 12877:1999PhST...83...83D 12826:1995PhRvL..74.4791Y 12783:1994CPL...229..486D 12537:The PubChem Project 12306: 12273: 11527: 11492: 10006: 9987: 9871: 9118: 8818: 8620: 8595: 8480: 8183: 7493: 7245: 6796: 6635: 6600: 6366: 6331: 6074: 6039: 5828: 5619: 5025: 4953: 4846: 4803:{\displaystyle S=1} 4688: 4652:{\displaystyle S=0} 4619: 4568: 4481: 4449: 4068:Pauli approximation 3811:{\textstyle (2l+1)} 3109:{\textstyle 2s+1=3} 3068:{\displaystyle S=1} 3042:{\textstyle 2s+1=1} 3001:{\displaystyle S=0} 2114:based on solutions 1303: 1268: 681: 523:Hartree–Fock method 360: g·mol 28: 12473:Isotopes of helium 12369: 12292: 12253: 12105: 11872: 11839: 11806:and J is known as 11792: 11747: 11673: 11598: 11506: 11471: 11383: 11300: 11262: 11160: 11072: 11043: 10878: 10736: 10566: 10265: 10108: 10060: 9992: 9973: 9910: 9857: 9731: 9610: 9566: 9363: 9327: 9104: 9039: 8961: 8880: 8804: 8628: 8606: 8581: 8440: 8420: 8367: 8306: 8245: 8184: 8169: 8152: 8113: 8074: 7883: 7822: 7758: 7686: 7649: 7593: 7553: 7473: 7456: 7416: 7225: 7205: 7170: 7135: 7026:{\textstyle H_{2}} 7023: 6999:{\textstyle H_{1}} 6996: 6969: 6934: 6899: 6832: 6780: 6732: 6619: 6584: 6525: 6437: 6350: 6315: 6263: 6213: 6058: 6023: 5972: 5857: 5812: 5732: 5620: 5603: 5529: 5381: 5359: 5350: 5285: 5220: 5145: 5080: 5078: 5070:↓ ↓ 5059: 5006: 4998:↑ ↑ 4987: 4937: 4923:↓ ↑ 4917:↑ ↓ 4892: 4830: 4800: 4773: 4768:↓ ↑ 4762:↑ ↓ 4737: 4672: 4649: 4620: 4603: 4554: 4553: 4516: 4467: 4450: 4433: 4410: 4404: 4398:↓ ↓ 4386:↓ ↑ 4372:↑ ↓ 4360:↑ ↑ 4319: 4266: 4196: 4167: 4128: 4074:with 4 components 4056: 3964: 3901: 3834: 3808: 3770: 3675: 3673: 3393: 3301: 3165: 3106: 3065: 3039: 2998: 2969: 2923: 2863: 2843: 2823: 2803: 2748: 2609:{\textstyle S_{z}} 2606: 2582:{\textstyle S^{2}} 2579: 2555:{\textstyle L_{z}} 2552: 2528:{\textstyle L^{2}} 2525: 2495: 2475: 2458:{\textstyle m_{s}} 2455: 2431:{\textstyle m_{l}} 2428: 2401: 2374: 2343: 2315: 2262: 2227: 2192: 2139: 2104: 2068: 2036: 1989: 1922: 1866: 1801: 1724: 1656: 1608: 1573: 1538: 1488: 1442: 1287: 1252: 1209: 1138: 1112: 1086: 1065: 1012: 945: 916: 887: 839: 660: 629: 551: 470:Infobox references 26: 13030:Physical Review A 12921:Physical Review A 12693:978-1-4757-0578-2 12587:978-1-108-49999-6 12503:Quantum mechanics 12401:ionization energy 12304: 12271: 12251: 12059: 11808:exchange integral 11671: 11596: 11561: 11504: 11469: 11381: 11347: 11332: 11292: 11231: 11192: 11140: 11070: 11013: 10995: 10826: 10734: 10695: 10662: 10626: 10518: 10412: 10381: 10213: 10106: 10009: 10008: 9908: 9843: 9729: 9691: 9607: 9542: 9485: 9450: 9417: 9361: 9325: 9296: 9237: 9178: 9120: 9037: 8959: 8945: 8876: 8820: 8645:many-body problem 8621: 8596: 8569: 7293: 7292: 6979:are eigenkets of 6830: 6778: 6704: 6669: 6617: 6582: 6523: 6435: 6400: 6348: 6313: 6208: 6147: 6110: 6056: 6021: 5871:spatial function 5634:spatial function 5318: 5317: 5253: 5252: 5185: 5184: 4911: 4910: 4860: 4859: 4756: 4755: 4702: 4701: 4541: 4184: 3974:. Note that here 3468: 3467: 3246: 3245: 2866:{\displaystyle L} 2846:{\displaystyle S} 2826:{\displaystyle n} 2027: 1854: 1789: 1712: 1644: 1476: 1437: 1376: 1339: 1285: 1250: 1170: 1089:{\displaystyle Z} 885: 837: 755: 730: 658: 608: 478:Chemical compound 476: 475: 103:Interactive image 13242: 13210: 13209: 13175: 13155: 13149: 13148: 13142: 13134: 13122: 13113: 13112: 13095: 13089: 13084: 13078: 13077: 13021: 13015: 13014: 13012: 12976: 12967: 12961: 12960: 12916: 12910: 12903: 12897: 12896: 12860: 12854: 12853: 12809: 12803: 12802: 12766: 12760: 12759: 12751: 12745: 12744: 12736: 12730: 12729: 12709: 12698: 12697: 12669: 12663: 12662: 12646: 12640: 12639: 12621: 12615: 12614: 12612: 12603: 12592: 12591: 12563: 12554: 12551: 12545: 12544: 12529: 12461: 12459: 12456: 12450: 12444: 12441: 12435: 12433: 12430: 12424: 12422: 12419: 12413: 12411: 12408: 12378: 12376: 12375: 12370: 12368: 12367: 12362: 12356: 12355: 12346: 12345: 12340: 12334: 12333: 12321: 12320: 12315: 12305: 12302: 12300: 12288: 12287: 12282: 12272: 12269: 12267: 12252: 12250: 12249: 12244: 12243: 12238: 12229: 12228: 12223: 12217: 12211: 12210: 12209: 12196: 12191: 12190: 12185: 12176: 12175: 12157: 12156: 12151: 12142: 12141: 12114: 12112: 12111: 12106: 12104: 12103: 12098: 12092: 12091: 12082: 12081: 12076: 12070: 12069: 12060: 12058: 12057: 12052: 12051: 12046: 12037: 12036: 12031: 12025: 12019: 12018: 12017: 12004: 12002: 12001: 11996: 11987: 11986: 11981: 11972: 11971: 11956: 11951: 11950: 11945: 11936: 11935: 11930: 11921: 11920: 11911: 11881: 11879: 11878: 11873: 11871: 11870: 11848: 11846: 11845: 11840: 11838: 11837: 11801: 11799: 11798: 11793: 11779: 11778: 11756: 11754: 11753: 11748: 11746: 11745: 11727: 11726: 11708: 11707: 11682: 11680: 11679: 11674: 11672: 11670: 11669: 11664: 11663: 11658: 11649: 11648: 11643: 11637: 11631: 11630: 11629: 11616: 11607: 11605: 11604: 11599: 11597: 11595: 11594: 11585: 11584: 11583: 11567: 11562: 11560: 11559: 11550: 11549: 11548: 11532: 11526: 11521: 11520: 11519: 11505: 11497: 11491: 11486: 11485: 11484: 11470: 11462: 11454: 11453: 11417: 11415: 11412: 11403: 11392: 11390: 11389: 11384: 11382: 11379: 11368: 11367: 11358: 11357: 11352: 11348: 11340: 11333: 11325: 11315:screening effect 11309: 11307: 11306: 11301: 11293: 11285: 11271: 11269: 11268: 11263: 11255: 11251: 11250: 11249: 11240: 11236: 11232: 11224: 11219: 11218: 11193: 11191: 11180: 11169: 11167: 11166: 11161: 11159: 11158: 11149: 11145: 11141: 11133: 11128: 11127: 11081: 11079: 11078: 11073: 11071: 11063: 11052: 11050: 11049: 11044: 11042: 11038: 11037: 11018: 11014: 11006: 11000: 10996: 10994: 10993: 10992: 10976: 10975: 10966: 10939: 10938: 10929: 10928: 10887: 10885: 10884: 10879: 10877: 10876: 10872: 10864: 10863: 10851: 10850: 10827: 10825: 10824: 10823: 10810: 10809: 10800: 10792: 10791: 10786: 10777: 10776: 10771: 10745: 10743: 10742: 10737: 10735: 10732: 10706: 10705: 10696: 10688: 10683: 10682: 10667: 10663: 10661: 10660: 10659: 10643: 10642: 10633: 10627: 10625: 10614: 10609: 10608: 10575: 10573: 10572: 10567: 10565: 10564: 10559: 10553: 10552: 10542: 10541: 10536: 10530: 10529: 10519: 10517: 10516: 10511: 10510: 10505: 10496: 10495: 10490: 10484: 10478: 10477: 10473: 10465: 10464: 10452: 10451: 10428: 10423: 10422: 10417: 10413: 10411: 10410: 10409: 10393: 10386: 10382: 10380: 10379: 10378: 10362: 10361: 10352: 10343: 10342: 10324: 10323: 10305: 10304: 10274: 10272: 10271: 10266: 10264: 10263: 10259: 10251: 10250: 10238: 10237: 10214: 10212: 10211: 10210: 10194: 10186: 10185: 10180: 10170: 10169: 10164: 10155: 10154: 10138: 10117: 10115: 10114: 10109: 10107: 10099: 10090: 10069: 10067: 10066: 10061: 10059: 10058: 10054: 10053: 10041: 10040: 10028: 10027: 10010: 10007: 10005: 10000: 9986: 9981: 9972: 9971: 9963: 9962: 9949: 9948: 9936: 9935: 9919: 9917: 9916: 9911: 9909: 9907: 9906: 9905: 9896: 9895: 9882: 9881: 9880: 9870: 9865: 9852: 9844: 9842: 9841: 9840: 9831: 9830: 9817: 9816: 9815: 9806: 9805: 9780: 9772: 9771: 9755: 9746: 9740: 9738: 9737: 9732: 9730: 9725: 9724: 9723: 9714: 9713: 9700: 9692: 9687: 9686: 9685: 9657: 9630: 9619: 9617: 9616: 9611: 9609: 9608: 9603: 9595: 9585: 9575: 9573: 9572: 9567: 9562: 9561: 9543: 9541: 9540: 9531: 9530: 9529: 9513: 9505: 9504: 9486: 9484: 9483: 9474: 9473: 9472: 9456: 9451: 9449: 9448: 9439: 9438: 9437: 9424: 9419: 9418: 9413: 9405: 9395: 9388:Screening effect 9383: 9381: 9378: 9372: 9370: 9369: 9364: 9362: 9359: 9336: 9334: 9333: 9328: 9326: 9324: 9323: 9314: 9313: 9312: 9299: 9297: 9289: 9284: 9283: 9278: 9272: 9271: 9262: 9261: 9256: 9250: 9249: 9240: 9239: 9238: 9236: 9235: 9226: 9222: 9221: 9209: 9208: 9189: 9179: 9177: 9176: 9171: 9170: 9165: 9156: 9155: 9150: 9144: 9138: 9137: 9136: 9123: 9121: 9119: 9117: 9112: 9103: 9102: 9092: 9091: 9082: 9071: 9070: 9048: 9046: 9045: 9040: 9038: 9036: 9035: 9030: 9029: 9024: 9015: 9014: 9009: 9003: 8997: 8996: 8995: 8982: 8970: 8968: 8967: 8962: 8960: 8957: 8946: 8944: 8943: 8934: 8933: 8932: 8919: 8908: 8907: 8889: 8887: 8886: 8881: 8879: 8878: 8877: 8875: 8874: 8865: 8861: 8860: 8848: 8847: 8831: 8821: 8819: 8817: 8812: 8799: 8798: 8789: 8781: 8780: 8768: 8767: 8743: 8742: 8730: 8729: 8702: 8701: 8688: 8687: 8675: 8674: 8637: 8635: 8634: 8629: 8627: 8623: 8622: 8619: 8614: 8602: 8597: 8594: 8589: 8577: 8570: 8568: 8567: 8566: 8553: 8552: 8551: 8542: 8541: 8528: 8520: 8519: 8518: 8517: 8500: 8499: 8498: 8497: 8479: 8468: 8467: 8466: 8454: 8453: 8429: 8427: 8426: 8421: 8419: 8418: 8406: 8405: 8376: 8374: 8373: 8368: 8363: 8362: 8349: 8348: 8315: 8313: 8312: 8307: 8302: 8301: 8288: 8287: 8254: 8252: 8251: 8246: 8241: 8240: 8227: 8226: 8193: 8191: 8190: 8185: 8182: 8177: 8161: 8159: 8158: 8153: 8145: 8134: 8122: 8120: 8119: 8114: 8106: 8095: 8083: 8081: 8080: 8075: 8070: 8069: 8064: 8055: 8054: 8053: 8052: 8040: 8039: 8027: 8026: 8009: 8008: 8003: 7994: 7993: 7992: 7991: 7979: 7978: 7966: 7965: 7945: 7944: 7939: 7930: 7929: 7924: 7915: 7914: 7892: 7890: 7889: 7884: 7879: 7878: 7865: 7864: 7851: 7850: 7831: 7829: 7828: 7823: 7818: 7817: 7804: 7803: 7790: 7789: 7767: 7765: 7764: 7759: 7757: 7756: 7741: 7740: 7728: 7727: 7712: 7711: 7695: 7693: 7692: 7687: 7685: 7684: 7675: 7674: 7658: 7656: 7655: 7650: 7648: 7647: 7632: 7631: 7619: 7618: 7602: 7600: 7599: 7594: 7592: 7591: 7582: 7581: 7562: 7560: 7559: 7554: 7549: 7548: 7543: 7534: 7533: 7521: 7520: 7515: 7506: 7505: 7492: 7481: 7465: 7463: 7462: 7457: 7455: 7454: 7442: 7441: 7425: 7423: 7422: 7417: 7409: 7408: 7403: 7394: 7393: 7381: 7380: 7375: 7366: 7365: 7350: 7349: 7344: 7335: 7334: 7322: 7321: 7316: 7307: 7306: 7294: 7288: 7284: 7276: 7275: 7270: 7260: 7259: 7254: 7244: 7233: 7215:is carried out. 7214: 7212: 7211: 7206: 7201: 7200: 7191: 7179: 7177: 7176: 7171: 7166: 7165: 7156: 7144: 7142: 7141: 7136: 7131: 7130: 7125: 7116: 7115: 7103: 7102: 7097: 7088: 7087: 7072: 7071: 7066: 7057: 7056: 7051: 7032: 7030: 7029: 7024: 7022: 7021: 7005: 7003: 7002: 6997: 6995: 6994: 6978: 6976: 6975: 6970: 6965: 6964: 6955: 6943: 6941: 6940: 6935: 6930: 6929: 6920: 6908: 6906: 6905: 6900: 6895: 6894: 6885: 6877: 6876: 6867: 6853: 6841: 6839: 6838: 6833: 6831: 6829: 6828: 6819: 6818: 6817: 6801: 6795: 6790: 6785: 6779: 6777: 6766: 6758: 6757: 6741: 6739: 6738: 6733: 6731: 6730: 6718: 6717: 6705: 6703: 6702: 6693: 6692: 6691: 6675: 6670: 6668: 6667: 6658: 6657: 6656: 6640: 6634: 6629: 6624: 6618: 6616: 6605: 6599: 6594: 6589: 6583: 6581: 6570: 6562: 6561: 6545: 6534: 6532: 6531: 6526: 6524: 6522: 6521: 6516: 6515: 6510: 6501: 6500: 6495: 6489: 6483: 6482: 6481: 6468: 6463: 6446: 6444: 6443: 6438: 6436: 6434: 6433: 6424: 6423: 6422: 6406: 6401: 6399: 6398: 6389: 6388: 6387: 6371: 6365: 6360: 6355: 6349: 6347: 6336: 6330: 6325: 6320: 6314: 6312: 6301: 6293: 6292: 6272: 6270: 6269: 6264: 6262: 6251: 6250: 6222: 6220: 6219: 6214: 6209: 6207: 6206: 6201: 6200: 6195: 6186: 6185: 6180: 6174: 6168: 6167: 6166: 6153: 6148: 6146: 6145: 6140: 6134: 6133: 6132: 6116: 6111: 6109: 6108: 6103: 6097: 6096: 6095: 6079: 6073: 6068: 6063: 6057: 6055: 6044: 6038: 6033: 6028: 6022: 6020: 6009: 5981: 5979: 5978: 5973: 5968: 5967: 5962: 5952: 5951: 5946: 5937: 5936: 5918: 5917: 5912: 5902: 5901: 5896: 5887: 5886: 5866: 5864: 5863: 5858: 5827: 5822: 5817: 5808: 5807: 5802: 5792: 5791: 5786: 5777: 5776: 5764: 5763: 5758: 5741: 5739: 5738: 5733: 5728: 5727: 5722: 5712: 5711: 5706: 5697: 5696: 5681: 5680: 5675: 5665: 5664: 5659: 5650: 5649: 5629: 5627: 5626: 5621: 5618: 5613: 5608: 5599: 5598: 5593: 5583: 5582: 5577: 5568: 5567: 5555: 5538: 5536: 5535: 5530: 5522: 5521: 5516: 5506: 5505: 5500: 5491: 5490: 5482: 5467: 5466: 5461: 5451: 5450: 5445: 5436: 5435: 5427: 5390: 5388: 5387: 5382: 5380: 5368: 5366: 5365: 5360: 5355: 5354: 5319: 5313: 5309: 5304: 5303: 5290: 5289: 5254: 5248: 5244: 5239: 5238: 5225: 5224: 5186: 5180: 5176: 5171: 5170: 5154: 5152: 5151: 5146: 5141: 5140: 5128: 5127: 5115: 5114: 5089: 5087: 5086: 5081: 5079: 5064: 5063: 5024: 5019: 5011: 4992: 4991: 4952: 4947: 4942: 4935: 4912: 4906: 4902: 4897: 4896: 4861: 4855: 4851: 4845: 4840: 4835: 4828: 4809: 4807: 4806: 4801: 4782: 4780: 4779: 4774: 4757: 4751: 4747: 4742: 4741: 4703: 4697: 4693: 4687: 4682: 4677: 4658: 4656: 4655: 4650: 4629: 4627: 4626: 4621: 4618: 4613: 4608: 4599: 4598: 4593: 4583: 4582: 4577: 4567: 4562: 4552: 4537: 4525: 4523: 4522: 4517: 4512: 4511: 4506: 4496: 4495: 4490: 4480: 4475: 4459: 4457: 4456: 4451: 4448: 4443: 4438: 4419: 4417: 4416: 4411: 4409: 4408: 4401: 4400: 4389: 4388: 4375: 4374: 4363: 4362: 4342: 4328: 4326: 4325: 4320: 4318: 4317: 4305: 4300: 4299: 4287: 4275: 4273: 4272: 4267: 4259: 4258: 4253: 4247: 4246: 4234: 4229: 4228: 4223: 4214: 4213: 4208: 4195: 4176: 4174: 4173: 4168: 4137: 4135: 4134: 4129: 4124: 4123: 4118: 4108: 4107: 4102: 4093: 4092: 4065: 4063: 4062: 4057: 4055: 4054: 4042: 4037: 4036: 4024: 4016: 4015: 4003: 3998: 3997: 3985: 3973: 3971: 3970: 3965: 3960: 3959: 3947: 3938: 3937: 3925: 3910: 3908: 3907: 3902: 3897: 3896: 3884: 3875: 3874: 3862: 3843: 3841: 3840: 3837:{\textstyle l=0} 3835: 3817: 3815: 3814: 3809: 3779: 3777: 3776: 3771: 3766: 3765: 3760: 3750: 3749: 3744: 3723: 3722: 3717: 3708: 3707: 3702: 3684: 3682: 3681: 3676: 3674: 3660: 3649: 3637: 3636: 3606: 3589: 3578: 3566: 3565: 3538: 3530: 3513: 3502: 3488: 3477: 3469: 3463: 3459: 3451: 3450: 3423: 3415: 3402: 3400: 3399: 3394: 3389: 3388: 3383: 3373: 3372: 3367: 3349: 3348: 3343: 3334: 3333: 3328: 3310: 3308: 3307: 3302: 3291: 3280: 3266: 3255: 3247: 3241: 3237: 3229: 3228: 3201: 3174: 3172: 3171: 3166: 3164: 3163: 3154: 3153: 3141: 3140: 3115: 3113: 3112: 3107: 3074: 3072: 3071: 3066: 3048: 3046: 3045: 3040: 3007: 3005: 3004: 2999: 2978: 2976: 2975: 2970: 2968: 2967: 2958: 2957: 2932: 2930: 2929: 2924: 2904: 2890: 2872: 2870: 2869: 2864: 2852: 2850: 2849: 2844: 2832: 2830: 2829: 2824: 2812: 2810: 2809: 2804: 2757: 2755: 2754: 2749: 2741: 2740: 2722: 2721: 2700: 2695: 2694: 2673: 2672: 2654: 2653: 2632: 2615: 2613: 2612: 2607: 2605: 2604: 2588: 2586: 2585: 2580: 2578: 2577: 2561: 2559: 2558: 2553: 2551: 2550: 2534: 2532: 2531: 2526: 2524: 2523: 2504: 2502: 2501: 2496: 2484: 2482: 2481: 2476: 2464: 2462: 2461: 2456: 2454: 2453: 2437: 2435: 2434: 2429: 2427: 2426: 2410: 2408: 2407: 2402: 2400: 2399: 2383: 2381: 2380: 2375: 2373: 2372: 2352: 2350: 2349: 2344: 2336: 2324: 2322: 2321: 2316: 2311: 2310: 2301: 2293: 2292: 2283: 2271: 2269: 2268: 2263: 2258: 2257: 2248: 2236: 2234: 2233: 2228: 2223: 2222: 2213: 2201: 2199: 2198: 2193: 2188: 2187: 2178: 2170: 2169: 2160: 2148: 2146: 2145: 2140: 2135: 2134: 2125: 2113: 2111: 2110: 2105: 2100: 2099: 2090: 2077: 2075: 2074: 2069: 2064: 2063: 2054: 2049: 2048: 2035: 2020: 2019: 2010: 1998: 1996: 1995: 1990: 1982: 1981: 1972: 1958: 1957: 1948: 1931: 1929: 1928: 1923: 1915: 1914: 1905: 1897: 1896: 1887: 1879: 1878: 1865: 1847: 1846: 1837: 1829: 1828: 1819: 1814: 1813: 1800: 1779: 1778: 1769: 1758: 1757: 1748: 1737: 1736: 1723: 1705: 1704: 1695: 1687: 1686: 1677: 1669: 1668: 1655: 1634: 1617: 1615: 1614: 1609: 1604: 1603: 1594: 1582: 1580: 1579: 1574: 1569: 1568: 1559: 1547: 1545: 1544: 1539: 1534: 1533: 1524: 1516: 1515: 1506: 1501: 1500: 1487: 1466: 1451: 1449: 1448: 1443: 1438: 1436: 1435: 1430: 1429: 1424: 1415: 1414: 1409: 1403: 1397: 1396: 1395: 1382: 1377: 1375: 1374: 1369: 1363: 1362: 1361: 1345: 1340: 1338: 1337: 1332: 1326: 1325: 1324: 1308: 1302: 1297: 1292: 1286: 1284: 1273: 1267: 1262: 1257: 1251: 1249: 1238: 1218: 1216: 1215: 1210: 1208: 1207: 1206: 1205: 1188: 1187: 1186: 1185: 1171: 1166: 1165: 1156: 1147: 1145: 1144: 1139: 1121: 1119: 1118: 1113: 1095: 1093: 1092: 1087: 1074: 1072: 1071: 1066: 1061: 1060: 1055: 1045: 1044: 1039: 1021: 1019: 1018: 1013: 1011: 1006: 1005: 1000: 991: 990: 985: 979: 971: 970: 954: 952: 951: 946: 944: 943: 938: 925: 923: 922: 917: 915: 914: 909: 896: 894: 893: 888: 886: 884: 873: 865: 848: 846: 845: 840: 838: 836: 835: 834: 825: 824: 808: 807: 798: 793: 792: 791: 790: 773: 772: 771: 770: 756: 751: 750: 741: 736: 732: 731: 729: 728: 727: 718: 717: 701: 700: 699: 686: 680: 675: 674: 673: 659: 657: 649: 648: 639: 628: 601: 600: 595: 585: 584: 579: 460: 454: 451: 450: 432: 403: 383:Thermochemistry 359: 358: 344: 337:Chemical formula 270: 234: 223: 212: 195: 173:Gmelin Reference 156: 145: 125: 105: 81: 36: 29: 25: 13250: 13249: 13245: 13244: 13243: 13241: 13240: 13239: 13215: 13214: 13213: 13160:Phys. Rev. Lett 13156: 13152: 13136: 13135: 13123: 13116: 13109: 13097: 13096: 13092: 13085: 13081: 13022: 13018: 12974: 12968: 12964: 12917: 12913: 12904: 12900: 12865:Physica Scripta 12861: 12857: 12810: 12806: 12767: 12763: 12752: 12748: 12737: 12733: 12726:10.18434/t4w30f 12710: 12701: 12694: 12678:. p. 274. 12670: 12666: 12647: 12643: 12636: 12622: 12618: 12610: 12604: 12595: 12588: 12564: 12557: 12552: 12548: 12531: 12530: 12526: 12522: 12517: 12468: 12457: 12454: 12452: 12451:, which equals 12442: 12439: 12437: 12431: 12428: 12426: 12420: 12417: 12415: 12409: 12406: 12404: 12399:Helium's first 12397: 12392: 12386: 12363: 12358: 12357: 12351: 12347: 12341: 12336: 12335: 12329: 12325: 12316: 12311: 12310: 12301: 12296: 12283: 12278: 12277: 12268: 12257: 12245: 12239: 12234: 12233: 12224: 12219: 12218: 12213: 12212: 12205: 12201: 12197: 12195: 12186: 12181: 12180: 12165: 12161: 12152: 12147: 12146: 12137: 12133: 12119: 12116: 12115: 12099: 12094: 12093: 12087: 12083: 12077: 12072: 12071: 12065: 12061: 12053: 12047: 12042: 12041: 12032: 12027: 12026: 12021: 12020: 12013: 12009: 12005: 12003: 11997: 11992: 11991: 11982: 11977: 11976: 11961: 11957: 11952: 11946: 11941: 11940: 11931: 11926: 11925: 11916: 11912: 11907: 11893: 11890: 11889: 11860: 11856: 11854: 11851: 11850: 11827: 11823: 11821: 11818: 11817: 11813:exchange energy 11804:direct integral 11768: 11764: 11762: 11759: 11758: 11735: 11731: 11716: 11712: 11703: 11699: 11691: 11688: 11687: 11665: 11659: 11654: 11653: 11644: 11639: 11638: 11633: 11632: 11625: 11621: 11617: 11615: 11613: 11610: 11609: 11590: 11586: 11579: 11575: 11568: 11566: 11555: 11551: 11544: 11540: 11533: 11531: 11522: 11515: 11511: 11510: 11496: 11487: 11480: 11476: 11475: 11461: 11449: 11445: 11443: 11440: 11439: 11436: 11413: 11410: 11408: 11402: 11396: 11378: 11363: 11359: 11353: 11339: 11335: 11334: 11324: 11322: 11319: 11318: 11284: 11276: 11273: 11272: 11245: 11241: 11223: 11214: 11210: 11203: 11199: 11198: 11194: 11184: 11179: 11177: 11174: 11173: 11154: 11150: 11132: 11123: 11119: 11112: 11108: 11094: 11091: 11090: 11088: 11062: 11060: 11057: 11056: 11030: 11026: 11022: 11005: 11001: 10988: 10984: 10977: 10971: 10967: 10965: 10961: 10934: 10930: 10924: 10920: 10903: 10900: 10899: 10868: 10859: 10855: 10846: 10842: 10832: 10828: 10819: 10815: 10811: 10805: 10801: 10799: 10787: 10782: 10781: 10772: 10767: 10766: 10758: 10755: 10754: 10731: 10701: 10697: 10687: 10678: 10674: 10655: 10651: 10644: 10638: 10634: 10632: 10628: 10618: 10613: 10604: 10600: 10583: 10580: 10579: 10560: 10555: 10554: 10548: 10544: 10537: 10532: 10531: 10525: 10521: 10512: 10506: 10501: 10500: 10491: 10486: 10485: 10480: 10479: 10469: 10460: 10456: 10447: 10443: 10433: 10429: 10427: 10418: 10405: 10401: 10397: 10392: 10388: 10387: 10374: 10370: 10363: 10357: 10353: 10351: 10347: 10338: 10334: 10316: 10312: 10300: 10296: 10279: 10276: 10275: 10255: 10246: 10242: 10233: 10229: 10219: 10215: 10206: 10202: 10198: 10193: 10181: 10176: 10175: 10165: 10160: 10159: 10150: 10146: 10144: 10141: 10140: 10137: 10131: 10124: 10098: 10096: 10093: 10092: 10085: 10083: 10076: 10049: 10045: 10036: 10032: 10023: 10019: 10015: 10011: 10001: 9996: 9988: 9982: 9977: 9970: 9958: 9954: 9944: 9940: 9931: 9927: 9925: 9922: 9921: 9901: 9897: 9891: 9887: 9883: 9876: 9872: 9866: 9861: 9853: 9851: 9836: 9832: 9826: 9822: 9818: 9811: 9807: 9801: 9797: 9781: 9779: 9767: 9763: 9761: 9758: 9757: 9754: 9748: 9742: 9719: 9715: 9709: 9705: 9701: 9699: 9681: 9677: 9658: 9656: 9636: 9633: 9632: 9621: 9596: 9594: 9593: 9591: 9588: 9587: 9576: 9557: 9553: 9536: 9532: 9525: 9521: 9514: 9512: 9500: 9496: 9479: 9475: 9468: 9464: 9457: 9455: 9444: 9440: 9433: 9429: 9425: 9423: 9406: 9404: 9403: 9401: 9398: 9397: 9393: 9390: 9379: 9376: 9374: 9358: 9344: 9341: 9340: 9319: 9315: 9308: 9304: 9300: 9298: 9288: 9279: 9274: 9273: 9267: 9263: 9257: 9252: 9251: 9245: 9241: 9231: 9227: 9217: 9213: 9204: 9200: 9190: 9188: 9184: 9180: 9172: 9166: 9161: 9160: 9151: 9146: 9145: 9140: 9139: 9132: 9128: 9124: 9122: 9113: 9108: 9098: 9094: 9093: 9087: 9083: 9081: 9060: 9056: 9054: 9051: 9050: 9031: 9025: 9020: 9019: 9010: 9005: 9004: 8999: 8998: 8991: 8987: 8983: 8981: 8979: 8976: 8975: 8956: 8939: 8935: 8928: 8924: 8920: 8918: 8903: 8899: 8897: 8894: 8893: 8870: 8866: 8856: 8852: 8843: 8839: 8832: 8830: 8826: 8822: 8813: 8808: 8800: 8794: 8790: 8788: 8776: 8772: 8751: 8747: 8738: 8734: 8713: 8709: 8697: 8693: 8683: 8679: 8670: 8666: 8664: 8661: 8660: 8657: 8615: 8610: 8601: 8590: 8585: 8576: 8575: 8571: 8562: 8558: 8554: 8547: 8543: 8537: 8533: 8529: 8527: 8513: 8509: 8508: 8504: 8493: 8489: 8488: 8484: 8469: 8462: 8458: 8449: 8445: 8444: 8438: 8435: 8434: 8414: 8410: 8401: 8397: 8389: 8386: 8385: 8358: 8354: 8344: 8340: 8321: 8318: 8317: 8297: 8293: 8283: 8279: 8260: 8257: 8256: 8236: 8232: 8222: 8218: 8199: 8196: 8195: 8178: 8173: 8167: 8164: 8163: 8141: 8130: 8128: 8125: 8124: 8102: 8091: 8089: 8086: 8085: 8065: 8060: 8059: 8048: 8044: 8035: 8031: 8022: 8018: 8017: 8013: 8004: 7999: 7998: 7987: 7983: 7974: 7970: 7961: 7957: 7956: 7952: 7940: 7935: 7934: 7925: 7920: 7919: 7904: 7900: 7898: 7895: 7894: 7874: 7870: 7860: 7856: 7846: 7842: 7837: 7834: 7833: 7813: 7809: 7799: 7795: 7785: 7781: 7776: 7773: 7772: 7749: 7745: 7736: 7732: 7720: 7716: 7707: 7703: 7701: 7698: 7697: 7680: 7676: 7670: 7666: 7664: 7661: 7660: 7640: 7636: 7627: 7623: 7614: 7610: 7608: 7605: 7604: 7587: 7583: 7577: 7573: 7571: 7568: 7567: 7544: 7539: 7538: 7529: 7525: 7516: 7511: 7510: 7501: 7497: 7482: 7477: 7471: 7468: 7467: 7450: 7446: 7437: 7433: 7431: 7428: 7427: 7404: 7399: 7398: 7389: 7385: 7376: 7371: 7370: 7361: 7357: 7345: 7340: 7339: 7330: 7326: 7317: 7312: 7311: 7302: 7298: 7283: 7271: 7266: 7265: 7255: 7250: 7249: 7234: 7229: 7223: 7220: 7219: 7196: 7192: 7187: 7185: 7182: 7181: 7161: 7157: 7152: 7150: 7147: 7146: 7126: 7121: 7120: 7111: 7107: 7098: 7093: 7092: 7083: 7079: 7067: 7062: 7061: 7052: 7047: 7046: 7038: 7035: 7034: 7017: 7013: 7011: 7008: 7007: 6990: 6986: 6984: 6981: 6980: 6960: 6956: 6951: 6949: 6946: 6945: 6925: 6921: 6916: 6914: 6911: 6910: 6890: 6886: 6881: 6872: 6868: 6863: 6849: 6847: 6844: 6843: 6824: 6820: 6813: 6809: 6802: 6800: 6791: 6786: 6781: 6770: 6765: 6753: 6749: 6747: 6744: 6743: 6726: 6722: 6713: 6709: 6698: 6694: 6687: 6683: 6676: 6674: 6663: 6659: 6652: 6648: 6641: 6639: 6630: 6625: 6620: 6609: 6604: 6595: 6590: 6585: 6574: 6569: 6557: 6553: 6551: 6548: 6547: 6544: 6538: 6517: 6511: 6506: 6505: 6496: 6491: 6490: 6485: 6484: 6477: 6473: 6469: 6467: 6456: 6454: 6451: 6450: 6429: 6425: 6418: 6414: 6407: 6405: 6394: 6390: 6383: 6379: 6372: 6370: 6361: 6356: 6351: 6340: 6335: 6326: 6321: 6316: 6305: 6300: 6288: 6284: 6282: 6279: 6278: 6255: 6246: 6242: 6234: 6231: 6230: 6202: 6196: 6191: 6190: 6181: 6176: 6175: 6170: 6169: 6162: 6158: 6154: 6152: 6141: 6136: 6135: 6128: 6124: 6117: 6115: 6104: 6099: 6098: 6091: 6087: 6080: 6078: 6069: 6064: 6059: 6048: 6043: 6034: 6029: 6024: 6013: 6008: 5997: 5994: 5993: 5988: 5963: 5958: 5957: 5947: 5942: 5941: 5932: 5928: 5913: 5908: 5907: 5897: 5892: 5891: 5882: 5878: 5876: 5873: 5872: 5823: 5818: 5813: 5803: 5798: 5797: 5787: 5782: 5781: 5772: 5768: 5759: 5754: 5753: 5751: 5748: 5747: 5723: 5718: 5717: 5707: 5702: 5701: 5692: 5688: 5676: 5671: 5670: 5660: 5655: 5654: 5645: 5641: 5639: 5636: 5635: 5614: 5609: 5604: 5594: 5589: 5588: 5578: 5573: 5572: 5563: 5559: 5551: 5549: 5546: 5545: 5517: 5512: 5511: 5501: 5496: 5495: 5483: 5478: 5477: 5462: 5457: 5456: 5446: 5441: 5440: 5428: 5423: 5422: 5420: 5417: 5416: 5376: 5374: 5371: 5370: 5349: 5348: 5343: 5337: 5336: 5331: 5321: 5320: 5308: 5299: 5295: 5284: 5283: 5278: 5272: 5271: 5266: 5256: 5255: 5243: 5234: 5230: 5219: 5218: 5210: 5204: 5203: 5198: 5188: 5187: 5175: 5166: 5162: 5160: 5157: 5156: 5136: 5132: 5123: 5119: 5110: 5106: 5101: 5098: 5097: 5077: 5076: 5058: 5057: 5052: 5046: 5045: 5040: 5030: 5029: 5020: 5012: 5007: 4986: 4985: 4980: 4974: 4973: 4968: 4958: 4957: 4948: 4943: 4938: 4933: 4932: 4901: 4891: 4890: 4885: 4879: 4878: 4873: 4863: 4862: 4850: 4841: 4836: 4831: 4825: 4823: 4820: 4819: 4789: 4786: 4785: 4783: 4746: 4736: 4735: 4730: 4721: 4720: 4715: 4705: 4704: 4692: 4683: 4678: 4673: 4670: 4667: 4666: 4638: 4635: 4634: 4614: 4609: 4604: 4594: 4589: 4588: 4578: 4573: 4572: 4563: 4558: 4545: 4533: 4531: 4528: 4527: 4507: 4502: 4501: 4491: 4486: 4485: 4476: 4471: 4465: 4462: 4461: 4444: 4439: 4434: 4431: 4428: 4427: 4403: 4402: 4396: 4392: 4390: 4384: 4380: 4377: 4376: 4370: 4366: 4364: 4358: 4354: 4347: 4346: 4338: 4336: 4333: 4332: 4313: 4309: 4301: 4295: 4291: 4283: 4281: 4278: 4277: 4254: 4249: 4248: 4239: 4235: 4230: 4224: 4219: 4218: 4209: 4204: 4203: 4188: 4182: 4179: 4178: 4143: 4140: 4139: 4119: 4114: 4113: 4103: 4098: 4097: 4085: 4081: 4079: 4076: 4075: 4050: 4046: 4038: 4032: 4028: 4020: 4011: 4007: 3999: 3993: 3989: 3981: 3979: 3976: 3975: 3955: 3951: 3943: 3933: 3929: 3921: 3916: 3913: 3912: 3892: 3888: 3880: 3870: 3866: 3858: 3853: 3850: 3849: 3823: 3820: 3819: 3788: 3785: 3784: 3761: 3756: 3755: 3745: 3740: 3739: 3718: 3713: 3712: 3703: 3698: 3697: 3689: 3686: 3685: 3672: 3671: 3656: 3645: 3611: 3607: 3602: 3585: 3574: 3543: 3539: 3534: 3528: 3527: 3509: 3498: 3484: 3473: 3458: 3428: 3424: 3419: 3412: 3410: 3407: 3406: 3384: 3379: 3378: 3368: 3363: 3362: 3344: 3339: 3338: 3329: 3324: 3323: 3315: 3312: 3311: 3287: 3276: 3262: 3251: 3236: 3206: 3202: 3197: 3195: 3192: 3191: 3159: 3155: 3149: 3145: 3136: 3132: 3121: 3118: 3117: 3086: 3083: 3082: 3054: 3051: 3050: 3019: 3016: 3015: 2987: 2984: 2983: 2963: 2959: 2944: 2940: 2938: 2935: 2934: 2900: 2886: 2878: 2875: 2874: 2858: 2855: 2854: 2838: 2835: 2834: 2818: 2815: 2814: 2765: 2762: 2761: 2736: 2732: 2717: 2713: 2696: 2684: 2680: 2668: 2664: 2649: 2645: 2628: 2623: 2620: 2619: 2600: 2596: 2594: 2591: 2590: 2573: 2569: 2567: 2564: 2563: 2546: 2542: 2540: 2537: 2536: 2519: 2515: 2513: 2510: 2509: 2490: 2487: 2486: 2470: 2467: 2466: 2449: 2445: 2443: 2440: 2439: 2422: 2418: 2416: 2413: 2412: 2395: 2391: 2389: 2386: 2385: 2368: 2364: 2362: 2359: 2358: 2332: 2330: 2327: 2326: 2306: 2302: 2297: 2288: 2284: 2279: 2277: 2274: 2273: 2253: 2249: 2244: 2242: 2239: 2238: 2218: 2214: 2209: 2207: 2204: 2203: 2183: 2179: 2174: 2165: 2161: 2156: 2154: 2151: 2150: 2130: 2126: 2121: 2119: 2116: 2115: 2095: 2091: 2086: 2084: 2081: 2080: 2059: 2055: 2050: 2041: 2037: 2031: 2015: 2011: 2006: 2004: 2001: 2000: 1977: 1973: 1968: 1953: 1949: 1944: 1939: 1936: 1935: 1910: 1906: 1901: 1892: 1888: 1883: 1871: 1867: 1858: 1842: 1838: 1833: 1824: 1820: 1815: 1806: 1802: 1793: 1774: 1770: 1765: 1753: 1749: 1744: 1729: 1725: 1716: 1700: 1696: 1691: 1682: 1678: 1673: 1661: 1657: 1648: 1630: 1625: 1622: 1621: 1599: 1595: 1590: 1588: 1585: 1584: 1564: 1560: 1555: 1553: 1550: 1549: 1529: 1525: 1520: 1511: 1507: 1502: 1493: 1489: 1480: 1462: 1460: 1457: 1456: 1431: 1425: 1420: 1419: 1410: 1405: 1404: 1399: 1398: 1391: 1387: 1383: 1381: 1370: 1365: 1364: 1357: 1353: 1346: 1344: 1333: 1328: 1327: 1320: 1316: 1309: 1307: 1298: 1293: 1288: 1277: 1272: 1263: 1258: 1253: 1242: 1237: 1226: 1223: 1222: 1201: 1197: 1196: 1192: 1181: 1177: 1176: 1172: 1161: 1157: 1155: 1153: 1150: 1149: 1127: 1124: 1123: 1101: 1098: 1097: 1081: 1078: 1077: 1056: 1051: 1050: 1040: 1035: 1034: 1029: 1026: 1025: 1007: 1001: 996: 995: 986: 981: 980: 975: 966: 962: 960: 957: 956: 939: 934: 933: 931: 928: 927: 910: 905: 904: 902: 899: 898: 874: 866: 864: 856: 853: 852: 830: 826: 820: 816: 809: 803: 799: 797: 786: 782: 781: 777: 766: 762: 761: 757: 746: 742: 740: 723: 719: 713: 709: 702: 695: 691: 687: 685: 676: 669: 665: 664: 650: 644: 640: 638: 634: 630: 612: 596: 591: 590: 580: 575: 574: 566: 563: 562: 543: 535:Albrecht Unsöld 479: 472: 467: 466: 465:  ?) 456: 452: 448: 444: 421: 404: 401: 394: 391: 368:Colourless gas 356: 354: 339: 325: 320: 319: 308: 305: 304: 301: 295: 294: 273: 253: 237: 224: 198: 175: 166: 148: 128: 108: 95: 84: 71: 57: 56: 40: 37: 24: 17: 12: 11: 5: 13248: 13238: 13237: 13232: 13230:Quantum models 13227: 13212: 13211: 13150: 13114: 13108:978-0070580404 13107: 13090: 13079: 13016: 12962: 12911: 12898: 12855: 12804: 12761: 12746: 12731: 12699: 12692: 12664: 12641: 12634: 12616: 12593: 12586: 12555: 12546: 12523: 12521: 12518: 12516: 12515: 12510: 12508:Quantum states 12505: 12500: 12495: 12490: 12485: 12480: 12475: 12469: 12467: 12464: 12396: 12393: 12388:Main article: 12385: 12382: 12366: 12361: 12354: 12350: 12344: 12339: 12332: 12328: 12324: 12319: 12314: 12309: 12299: 12295: 12291: 12286: 12281: 12276: 12266: 12263: 12260: 12256: 12248: 12242: 12237: 12232: 12227: 12222: 12216: 12208: 12204: 12200: 12194: 12189: 12184: 12179: 12174: 12171: 12168: 12164: 12160: 12155: 12150: 12145: 12140: 12136: 12132: 12129: 12126: 12123: 12102: 12097: 12090: 12086: 12080: 12075: 12068: 12064: 12056: 12050: 12045: 12040: 12035: 12030: 12024: 12016: 12012: 12008: 12000: 11995: 11990: 11985: 11980: 11975: 11970: 11967: 11964: 11960: 11955: 11949: 11944: 11939: 11934: 11929: 11924: 11919: 11915: 11910: 11906: 11903: 11900: 11897: 11869: 11866: 11863: 11859: 11836: 11833: 11830: 11826: 11791: 11788: 11785: 11782: 11777: 11774: 11771: 11767: 11744: 11741: 11738: 11734: 11730: 11725: 11722: 11719: 11715: 11711: 11706: 11702: 11698: 11695: 11668: 11662: 11657: 11652: 11647: 11642: 11636: 11628: 11624: 11620: 11593: 11589: 11582: 11578: 11574: 11571: 11565: 11558: 11554: 11547: 11543: 11539: 11536: 11530: 11525: 11518: 11514: 11509: 11503: 11500: 11495: 11490: 11483: 11479: 11474: 11468: 11465: 11460: 11457: 11452: 11448: 11435: 11432: 11400: 11377: 11374: 11371: 11366: 11362: 11356: 11351: 11346: 11343: 11338: 11331: 11328: 11299: 11296: 11291: 11288: 11283: 11280: 11261: 11258: 11254: 11248: 11244: 11239: 11235: 11230: 11227: 11222: 11217: 11213: 11209: 11206: 11202: 11197: 11190: 11187: 11183: 11157: 11153: 11148: 11144: 11139: 11136: 11131: 11126: 11122: 11118: 11115: 11111: 11107: 11104: 11101: 11098: 11086: 11069: 11066: 11041: 11036: 11033: 11029: 11025: 11021: 11017: 11012: 11009: 11004: 10999: 10991: 10987: 10983: 10980: 10974: 10970: 10964: 10960: 10957: 10954: 10951: 10948: 10945: 10942: 10937: 10933: 10927: 10923: 10919: 10916: 10913: 10910: 10907: 10875: 10871: 10867: 10862: 10858: 10854: 10849: 10845: 10841: 10838: 10835: 10831: 10822: 10818: 10814: 10808: 10804: 10798: 10795: 10790: 10785: 10780: 10775: 10770: 10765: 10762: 10730: 10727: 10724: 10721: 10718: 10715: 10712: 10709: 10704: 10700: 10694: 10691: 10686: 10681: 10677: 10673: 10670: 10666: 10658: 10654: 10650: 10647: 10641: 10637: 10631: 10624: 10621: 10617: 10612: 10607: 10603: 10599: 10596: 10593: 10590: 10587: 10563: 10558: 10551: 10547: 10540: 10535: 10528: 10524: 10515: 10509: 10504: 10499: 10494: 10489: 10483: 10476: 10472: 10468: 10463: 10459: 10455: 10450: 10446: 10442: 10439: 10436: 10432: 10426: 10421: 10416: 10408: 10404: 10400: 10396: 10391: 10385: 10377: 10373: 10369: 10366: 10360: 10356: 10350: 10346: 10341: 10337: 10333: 10330: 10327: 10322: 10319: 10315: 10311: 10308: 10303: 10299: 10295: 10292: 10289: 10286: 10283: 10262: 10258: 10254: 10249: 10245: 10241: 10236: 10232: 10228: 10225: 10222: 10218: 10209: 10205: 10201: 10197: 10192: 10189: 10184: 10179: 10173: 10168: 10163: 10158: 10153: 10149: 10135: 10123: 10120: 10105: 10102: 10081: 10074: 10057: 10052: 10048: 10044: 10039: 10035: 10031: 10026: 10022: 10018: 10014: 10004: 9999: 9995: 9991: 9985: 9980: 9976: 9969: 9966: 9961: 9957: 9953: 9947: 9943: 9939: 9934: 9930: 9904: 9900: 9894: 9890: 9886: 9879: 9875: 9869: 9864: 9860: 9856: 9850: 9847: 9839: 9835: 9829: 9825: 9821: 9814: 9810: 9804: 9800: 9796: 9793: 9790: 9787: 9784: 9778: 9775: 9770: 9766: 9752: 9728: 9722: 9718: 9712: 9708: 9704: 9698: 9695: 9690: 9684: 9680: 9676: 9673: 9670: 9667: 9664: 9661: 9655: 9652: 9649: 9646: 9643: 9640: 9606: 9602: 9599: 9565: 9560: 9556: 9552: 9549: 9546: 9539: 9535: 9528: 9524: 9520: 9517: 9511: 9508: 9503: 9499: 9495: 9492: 9489: 9482: 9478: 9471: 9467: 9463: 9460: 9454: 9447: 9443: 9436: 9432: 9428: 9422: 9416: 9412: 9409: 9389: 9386: 9357: 9354: 9351: 9348: 9322: 9318: 9311: 9307: 9303: 9295: 9292: 9287: 9282: 9277: 9270: 9266: 9260: 9255: 9248: 9244: 9234: 9230: 9225: 9220: 9216: 9212: 9207: 9203: 9199: 9196: 9193: 9187: 9183: 9175: 9169: 9164: 9159: 9154: 9149: 9143: 9135: 9131: 9127: 9116: 9111: 9107: 9101: 9097: 9090: 9086: 9080: 9077: 9074: 9069: 9066: 9063: 9059: 9034: 9028: 9023: 9018: 9013: 9008: 9002: 8994: 8990: 8986: 8955: 8952: 8949: 8942: 8938: 8931: 8927: 8923: 8917: 8914: 8911: 8906: 8902: 8873: 8869: 8864: 8859: 8855: 8851: 8846: 8842: 8838: 8835: 8829: 8825: 8816: 8811: 8807: 8803: 8797: 8793: 8787: 8784: 8779: 8775: 8771: 8766: 8763: 8760: 8757: 8754: 8750: 8746: 8741: 8737: 8733: 8728: 8725: 8722: 8719: 8716: 8712: 8708: 8705: 8700: 8696: 8692: 8686: 8682: 8678: 8673: 8669: 8656: 8653: 8626: 8618: 8613: 8609: 8605: 8600: 8593: 8588: 8584: 8580: 8574: 8565: 8561: 8557: 8550: 8546: 8540: 8536: 8532: 8526: 8523: 8516: 8512: 8507: 8503: 8496: 8492: 8487: 8483: 8478: 8475: 8472: 8465: 8461: 8457: 8452: 8448: 8443: 8417: 8413: 8409: 8404: 8400: 8396: 8393: 8366: 8361: 8357: 8353: 8347: 8343: 8339: 8335: 8332: 8328: 8325: 8305: 8300: 8296: 8292: 8286: 8282: 8278: 8274: 8271: 8267: 8264: 8244: 8239: 8235: 8231: 8225: 8221: 8217: 8213: 8210: 8206: 8203: 8181: 8176: 8172: 8151: 8148: 8144: 8140: 8137: 8133: 8112: 8109: 8105: 8101: 8098: 8094: 8073: 8068: 8063: 8058: 8051: 8047: 8043: 8038: 8034: 8030: 8025: 8021: 8016: 8012: 8007: 8002: 7997: 7990: 7986: 7982: 7977: 7973: 7969: 7964: 7960: 7955: 7951: 7948: 7943: 7938: 7933: 7928: 7923: 7918: 7913: 7910: 7907: 7903: 7882: 7877: 7873: 7869: 7863: 7859: 7855: 7849: 7845: 7841: 7821: 7816: 7812: 7808: 7802: 7798: 7794: 7788: 7784: 7780: 7755: 7752: 7748: 7744: 7739: 7735: 7731: 7726: 7723: 7719: 7715: 7710: 7706: 7683: 7679: 7673: 7669: 7646: 7643: 7639: 7635: 7630: 7626: 7622: 7617: 7613: 7590: 7586: 7580: 7576: 7552: 7547: 7542: 7537: 7532: 7528: 7524: 7519: 7514: 7509: 7504: 7500: 7496: 7491: 7488: 7485: 7480: 7476: 7453: 7449: 7445: 7440: 7436: 7415: 7412: 7407: 7402: 7397: 7392: 7388: 7384: 7379: 7374: 7369: 7364: 7360: 7356: 7353: 7348: 7343: 7338: 7333: 7329: 7325: 7320: 7315: 7310: 7305: 7301: 7297: 7291: 7287: 7282: 7279: 7274: 7269: 7264: 7258: 7253: 7248: 7243: 7240: 7237: 7232: 7228: 7204: 7199: 7195: 7190: 7169: 7164: 7160: 7155: 7134: 7129: 7124: 7119: 7114: 7110: 7106: 7101: 7096: 7091: 7086: 7082: 7078: 7075: 7070: 7065: 7060: 7055: 7050: 7045: 7042: 7020: 7016: 6993: 6989: 6968: 6963: 6959: 6954: 6933: 6928: 6924: 6919: 6898: 6893: 6889: 6884: 6880: 6875: 6871: 6866: 6862: 6859: 6856: 6852: 6827: 6823: 6816: 6812: 6808: 6805: 6799: 6794: 6789: 6784: 6776: 6773: 6769: 6764: 6761: 6756: 6752: 6729: 6725: 6721: 6716: 6712: 6708: 6701: 6697: 6690: 6686: 6682: 6679: 6673: 6666: 6662: 6655: 6651: 6647: 6644: 6638: 6633: 6628: 6623: 6615: 6612: 6608: 6603: 6598: 6593: 6588: 6580: 6577: 6573: 6568: 6565: 6560: 6556: 6542: 6520: 6514: 6509: 6504: 6499: 6494: 6488: 6480: 6476: 6472: 6466: 6462: 6459: 6432: 6428: 6421: 6417: 6413: 6410: 6404: 6397: 6393: 6386: 6382: 6378: 6375: 6369: 6364: 6359: 6354: 6346: 6343: 6339: 6334: 6329: 6324: 6319: 6311: 6308: 6304: 6299: 6296: 6291: 6287: 6261: 6258: 6254: 6249: 6245: 6241: 6238: 6212: 6205: 6199: 6194: 6189: 6184: 6179: 6173: 6165: 6161: 6157: 6151: 6144: 6139: 6131: 6127: 6123: 6120: 6114: 6107: 6102: 6094: 6090: 6086: 6083: 6077: 6072: 6067: 6062: 6054: 6051: 6047: 6042: 6037: 6032: 6027: 6019: 6016: 6012: 6007: 6004: 6001: 5987: 5984: 5971: 5966: 5961: 5955: 5950: 5945: 5940: 5935: 5931: 5927: 5924: 5921: 5916: 5911: 5905: 5900: 5895: 5890: 5885: 5881: 5869:antisymmetric 5856: 5853: 5850: 5847: 5844: 5841: 5838: 5835: 5831: 5826: 5821: 5816: 5811: 5806: 5801: 5795: 5790: 5785: 5780: 5775: 5771: 5767: 5762: 5757: 5731: 5726: 5721: 5715: 5710: 5705: 5700: 5695: 5691: 5687: 5684: 5679: 5674: 5668: 5663: 5658: 5653: 5648: 5644: 5617: 5612: 5607: 5602: 5597: 5592: 5586: 5581: 5576: 5571: 5566: 5562: 5558: 5554: 5528: 5525: 5520: 5515: 5509: 5504: 5499: 5494: 5489: 5486: 5481: 5476: 5473: 5470: 5465: 5460: 5454: 5449: 5444: 5439: 5434: 5431: 5426: 5379: 5358: 5353: 5347: 5344: 5342: 5339: 5338: 5335: 5332: 5330: 5327: 5326: 5324: 5316: 5312: 5307: 5302: 5298: 5293: 5288: 5282: 5279: 5277: 5274: 5273: 5270: 5267: 5265: 5262: 5261: 5259: 5251: 5247: 5242: 5237: 5233: 5228: 5223: 5217: 5214: 5211: 5209: 5206: 5205: 5202: 5199: 5197: 5194: 5193: 5191: 5183: 5179: 5174: 5169: 5165: 5144: 5139: 5135: 5131: 5126: 5122: 5118: 5113: 5109: 5105: 5075: 5071: 5067: 5062: 5056: 5053: 5051: 5048: 5047: 5044: 5041: 5039: 5036: 5035: 5033: 5028: 5023: 5018: 5015: 5010: 5003: 4999: 4995: 4990: 4984: 4981: 4979: 4976: 4975: 4972: 4969: 4967: 4964: 4963: 4961: 4956: 4951: 4946: 4941: 4936: 4934: 4931: 4927: 4924: 4921: 4918: 4915: 4909: 4905: 4900: 4895: 4889: 4886: 4884: 4881: 4880: 4877: 4874: 4872: 4869: 4868: 4866: 4858: 4854: 4849: 4844: 4839: 4834: 4829: 4827: 4799: 4796: 4793: 4772: 4769: 4766: 4763: 4760: 4754: 4750: 4745: 4740: 4734: 4731: 4729: 4726: 4723: 4722: 4719: 4716: 4714: 4711: 4710: 4708: 4700: 4696: 4691: 4686: 4681: 4676: 4648: 4645: 4642: 4617: 4612: 4607: 4602: 4597: 4592: 4586: 4581: 4576: 4571: 4566: 4561: 4557: 4551: 4548: 4544: 4540: 4536: 4515: 4510: 4505: 4499: 4494: 4489: 4484: 4479: 4474: 4470: 4447: 4442: 4437: 4407: 4399: 4395: 4391: 4387: 4383: 4379: 4378: 4373: 4369: 4365: 4361: 4357: 4353: 4352: 4350: 4345: 4341: 4316: 4312: 4308: 4304: 4298: 4294: 4290: 4286: 4265: 4262: 4257: 4252: 4245: 4242: 4238: 4233: 4227: 4222: 4217: 4212: 4207: 4202: 4199: 4194: 4191: 4187: 4166: 4163: 4160: 4156: 4153: 4150: 4147: 4127: 4122: 4117: 4111: 4106: 4101: 4096: 4091: 4088: 4084: 4053: 4049: 4045: 4041: 4035: 4031: 4027: 4023: 4019: 4014: 4010: 4006: 4002: 3996: 3992: 3988: 3984: 3963: 3958: 3954: 3950: 3946: 3942: 3936: 3932: 3928: 3924: 3920: 3900: 3895: 3891: 3887: 3883: 3879: 3873: 3869: 3865: 3861: 3857: 3833: 3830: 3827: 3807: 3804: 3801: 3798: 3795: 3792: 3769: 3764: 3759: 3754: 3748: 3743: 3738: 3735: 3732: 3729: 3726: 3721: 3716: 3711: 3706: 3701: 3696: 3693: 3670: 3666: 3663: 3659: 3655: 3652: 3648: 3643: 3640: 3635: 3632: 3629: 3626: 3623: 3620: 3617: 3614: 3610: 3605: 3599: 3595: 3592: 3588: 3584: 3581: 3577: 3572: 3569: 3564: 3561: 3558: 3555: 3552: 3549: 3546: 3542: 3537: 3533: 3531: 3529: 3526: 3522: 3519: 3516: 3512: 3508: 3505: 3501: 3497: 3494: 3491: 3487: 3483: 3480: 3476: 3472: 3466: 3462: 3457: 3454: 3449: 3446: 3443: 3440: 3437: 3434: 3431: 3427: 3422: 3418: 3416: 3414: 3392: 3387: 3382: 3377: 3371: 3366: 3361: 3358: 3355: 3352: 3347: 3342: 3337: 3332: 3327: 3322: 3319: 3300: 3297: 3294: 3290: 3286: 3283: 3279: 3275: 3272: 3269: 3265: 3261: 3258: 3254: 3250: 3244: 3240: 3235: 3232: 3227: 3224: 3221: 3218: 3215: 3212: 3209: 3205: 3200: 3162: 3158: 3152: 3148: 3144: 3139: 3135: 3131: 3128: 3125: 3105: 3102: 3099: 3096: 3093: 3090: 3064: 3061: 3058: 3038: 3035: 3032: 3029: 3026: 3023: 2997: 2994: 2991: 2966: 2962: 2956: 2953: 2950: 2947: 2943: 2933:is denoted by 2922: 2919: 2916: 2913: 2910: 2907: 2903: 2899: 2896: 2893: 2889: 2885: 2882: 2862: 2842: 2822: 2802: 2799: 2796: 2793: 2790: 2787: 2784: 2781: 2778: 2775: 2772: 2769: 2747: 2744: 2739: 2735: 2731: 2728: 2725: 2720: 2716: 2712: 2709: 2706: 2703: 2699: 2693: 2690: 2687: 2683: 2679: 2676: 2671: 2667: 2663: 2660: 2657: 2652: 2648: 2644: 2641: 2638: 2635: 2631: 2627: 2603: 2599: 2576: 2572: 2549: 2545: 2522: 2518: 2498:{\textstyle s} 2494: 2478:{\textstyle s} 2474: 2452: 2448: 2425: 2421: 2398: 2394: 2371: 2367: 2342: 2339: 2335: 2314: 2309: 2305: 2300: 2296: 2291: 2287: 2282: 2261: 2256: 2252: 2247: 2226: 2221: 2217: 2212: 2191: 2186: 2182: 2177: 2173: 2168: 2164: 2159: 2138: 2133: 2129: 2124: 2103: 2098: 2094: 2089: 2067: 2062: 2058: 2053: 2047: 2044: 2040: 2034: 2030: 2026: 2023: 2018: 2014: 2009: 1988: 1985: 1980: 1976: 1971: 1967: 1964: 1961: 1956: 1952: 1947: 1943: 1921: 1918: 1913: 1909: 1904: 1900: 1895: 1891: 1886: 1882: 1877: 1874: 1870: 1864: 1861: 1857: 1853: 1850: 1845: 1841: 1836: 1832: 1827: 1823: 1818: 1812: 1809: 1805: 1799: 1796: 1792: 1788: 1785: 1782: 1777: 1773: 1768: 1764: 1761: 1756: 1752: 1747: 1743: 1740: 1735: 1732: 1728: 1722: 1719: 1715: 1711: 1708: 1703: 1699: 1694: 1690: 1685: 1681: 1676: 1672: 1667: 1664: 1660: 1654: 1651: 1647: 1643: 1640: 1637: 1633: 1629: 1607: 1602: 1598: 1593: 1572: 1567: 1563: 1558: 1537: 1532: 1528: 1523: 1519: 1514: 1510: 1505: 1499: 1496: 1492: 1486: 1483: 1479: 1475: 1472: 1469: 1465: 1441: 1434: 1428: 1423: 1418: 1413: 1408: 1402: 1394: 1390: 1386: 1380: 1373: 1368: 1360: 1356: 1352: 1349: 1343: 1336: 1331: 1323: 1319: 1315: 1312: 1306: 1301: 1296: 1291: 1283: 1280: 1276: 1271: 1266: 1261: 1256: 1248: 1245: 1241: 1236: 1233: 1230: 1204: 1200: 1195: 1191: 1184: 1180: 1175: 1169: 1164: 1160: 1137: 1134: 1131: 1111: 1108: 1105: 1085: 1064: 1059: 1054: 1048: 1043: 1038: 1033: 1010: 1004: 999: 994: 989: 984: 978: 974: 969: 965: 942: 937: 913: 908: 883: 880: 877: 872: 869: 863: 860: 833: 829: 823: 819: 815: 812: 806: 802: 796: 789: 785: 780: 776: 769: 765: 760: 754: 749: 745: 739: 735: 726: 722: 716: 712: 708: 705: 698: 694: 690: 684: 679: 672: 668: 663: 656: 653: 647: 643: 637: 633: 627: 624: 621: 618: 615: 611: 607: 604: 599: 594: 588: 583: 578: 573: 570: 542: 539: 477: 474: 473: 468: 446: 445: 441:standard state 438: 435: 434: 422: 417: 414: 413: 409: 408: 405: 399: 388: 385: 384: 380: 379: 376: 370: 369: 366: 362: 361: 352: 346: 345: 340: 335: 332: 331: 327: 326: 324: 323: 315: 314: 313: 310: 309: 307: 306: 302: 299: 298: 290: 289: 288: 285: 284: 281: 275: 274: 272: 271: 263: 261: 255: 254: 252: 251: 247: 245: 239: 238: 236: 235: 227: 225: 217: 214: 213: 206: 200: 199: 197: 196: 188: 186: 180: 179: 176: 171: 168: 167: 165: 164: 160: 158: 150: 149: 147: 146: 138: 136: 130: 129: 127: 126: 118: 116: 110: 109: 107: 106: 98: 96: 89: 86: 85: 83: 82: 74: 72: 67: 64: 63: 59: 58: 54: 53: 47: 46: 42: 41: 38: 16:Atom of helium 15: 9: 6: 4: 3: 2: 13247: 13236: 13233: 13231: 13228: 13226: 13223: 13222: 13220: 13207: 13203: 13199: 13195: 13191: 13187: 13183: 13179: 13174: 13169: 13166:(6): 063001. 13165: 13161: 13154: 13146: 13140: 13132: 13128: 13121: 13119: 13110: 13104: 13100: 13094: 13088: 13083: 13075: 13071: 13067: 13063: 13059: 13055: 13051: 13047: 13043: 13039: 13035: 13031: 13027: 13020: 13011: 13010:11383/1679348 13006: 13002: 12998: 12994: 12990: 12987:(6): 060101. 12986: 12982: 12981: 12973: 12966: 12958: 12954: 12950: 12946: 12942: 12938: 12934: 12930: 12926: 12922: 12915: 12908: 12902: 12894: 12890: 12886: 12882: 12878: 12874: 12870: 12866: 12859: 12851: 12847: 12843: 12839: 12835: 12831: 12827: 12823: 12819: 12815: 12808: 12800: 12796: 12792: 12788: 12784: 12780: 12776: 12772: 12765: 12757: 12750: 12742: 12735: 12727: 12723: 12719: 12715: 12708: 12706: 12704: 12695: 12689: 12685: 12681: 12677: 12676: 12668: 12660: 12656: 12652: 12645: 12637: 12635:3-323-00011-0 12631: 12627: 12620: 12609: 12602: 12600: 12598: 12589: 12583: 12579: 12575: 12571: 12570: 12562: 12560: 12550: 12542: 12538: 12534: 12528: 12524: 12514: 12511: 12509: 12506: 12504: 12501: 12499: 12496: 12494: 12491: 12489: 12486: 12484: 12481: 12479: 12476: 12474: 12471: 12470: 12463: 12448: 12402: 12391: 12381: 12364: 12352: 12348: 12342: 12330: 12326: 12317: 12297: 12293: 12284: 12264: 12261: 12258: 12254: 12240: 12230: 12225: 12206: 12202: 12198: 12187: 12172: 12169: 12166: 12162: 12153: 12138: 12134: 12130: 12127: 12124: 12121: 12100: 12088: 12084: 12078: 12066: 12062: 12048: 12038: 12033: 12014: 12010: 12006: 11998: 11983: 11968: 11965: 11962: 11958: 11947: 11932: 11917: 11913: 11904: 11901: 11898: 11895: 11887: 11884: 11864: 11831: 11815: 11814: 11809: 11805: 11789: 11786: 11783: 11780: 11772: 11739: 11728: 11723: 11720: 11717: 11713: 11709: 11704: 11700: 11696: 11693: 11684: 11660: 11650: 11645: 11626: 11622: 11618: 11591: 11587: 11580: 11576: 11572: 11569: 11563: 11556: 11552: 11545: 11541: 11537: 11534: 11528: 11523: 11516: 11512: 11501: 11498: 11493: 11488: 11481: 11477: 11466: 11463: 11458: 11455: 11450: 11446: 11431: 11429: 11425: 11421: 11405: 11399: 11395:Where again, 11393: 11375: 11372: 11369: 11364: 11360: 11354: 11349: 11344: 11341: 11336: 11329: 11326: 11316: 11310: 11297: 11294: 11289: 11286: 11281: 11278: 11259: 11256: 11252: 11246: 11242: 11237: 11233: 11228: 11225: 11220: 11215: 11211: 11207: 11204: 11200: 11195: 11188: 11185: 11181: 11170: 11155: 11151: 11146: 11142: 11137: 11134: 11129: 11124: 11120: 11116: 11113: 11109: 11105: 11099: 11085: 11067: 11064: 11053: 11039: 11034: 11031: 11027: 11023: 11019: 11015: 11010: 11007: 11002: 10997: 10989: 10985: 10981: 10978: 10972: 10968: 10962: 10955: 10952: 10949: 10943: 10940: 10935: 10931: 10925: 10921: 10917: 10914: 10908: 10897: 10893: 10888: 10873: 10869: 10860: 10856: 10852: 10847: 10843: 10836: 10833: 10829: 10820: 10816: 10812: 10806: 10802: 10796: 10788: 10778: 10773: 10760: 10752: 10746: 10728: 10725: 10722: 10719: 10716: 10713: 10710: 10707: 10702: 10698: 10692: 10689: 10684: 10679: 10675: 10671: 10668: 10664: 10656: 10652: 10648: 10645: 10639: 10635: 10629: 10622: 10619: 10615: 10610: 10605: 10601: 10597: 10594: 10588: 10576: 10561: 10549: 10545: 10538: 10526: 10522: 10507: 10497: 10492: 10474: 10470: 10461: 10457: 10453: 10448: 10444: 10437: 10434: 10430: 10424: 10419: 10414: 10406: 10402: 10398: 10394: 10389: 10383: 10375: 10371: 10367: 10364: 10358: 10354: 10348: 10344: 10339: 10335: 10331: 10328: 10320: 10317: 10313: 10306: 10301: 10297: 10293: 10290: 10284: 10260: 10256: 10247: 10243: 10239: 10234: 10230: 10223: 10220: 10216: 10207: 10203: 10199: 10195: 10190: 10182: 10171: 10166: 10151: 10147: 10134: 10129: 10119: 10103: 10100: 10088: 10080: 10073: 10050: 10046: 10042: 10037: 10033: 10024: 10020: 10016: 10012: 10002: 9997: 9993: 9989: 9983: 9978: 9974: 9967: 9959: 9955: 9951: 9945: 9941: 9932: 9928: 9902: 9898: 9892: 9888: 9884: 9877: 9873: 9867: 9862: 9858: 9854: 9848: 9845: 9837: 9833: 9827: 9823: 9819: 9812: 9808: 9802: 9794: 9791: 9788: 9782: 9776: 9773: 9768: 9764: 9751: 9745: 9726: 9720: 9716: 9710: 9706: 9702: 9696: 9693: 9688: 9682: 9678: 9671: 9668: 9665: 9659: 9653: 9650: 9644: 9638: 9628: 9624: 9600: 9597: 9583: 9579: 9558: 9554: 9547: 9544: 9537: 9533: 9526: 9522: 9518: 9515: 9509: 9501: 9497: 9490: 9487: 9480: 9476: 9469: 9465: 9461: 9458: 9452: 9445: 9441: 9434: 9430: 9426: 9420: 9410: 9407: 9385: 9355: 9352: 9349: 9346: 9337: 9320: 9316: 9309: 9305: 9301: 9293: 9290: 9285: 9280: 9268: 9264: 9258: 9246: 9242: 9232: 9228: 9218: 9214: 9210: 9205: 9201: 9194: 9191: 9185: 9181: 9167: 9157: 9152: 9133: 9129: 9125: 9114: 9109: 9105: 9099: 9095: 9088: 9084: 9078: 9075: 9072: 9064: 9026: 9016: 9011: 8992: 8988: 8984: 8972: 8953: 8950: 8947: 8940: 8936: 8929: 8925: 8921: 8915: 8912: 8909: 8904: 8900: 8890: 8871: 8867: 8857: 8853: 8849: 8844: 8840: 8833: 8827: 8823: 8814: 8809: 8805: 8801: 8795: 8791: 8785: 8777: 8773: 8764: 8761: 8758: 8755: 8752: 8748: 8739: 8735: 8726: 8723: 8720: 8717: 8714: 8710: 8706: 8698: 8694: 8690: 8684: 8680: 8671: 8667: 8652: 8650: 8646: 8641: 8638: 8624: 8616: 8611: 8607: 8603: 8598: 8591: 8586: 8582: 8578: 8572: 8563: 8559: 8555: 8548: 8544: 8538: 8534: 8530: 8524: 8521: 8514: 8510: 8505: 8501: 8494: 8490: 8485: 8481: 8473: 8463: 8459: 8455: 8450: 8446: 8441: 8431: 8415: 8411: 8407: 8402: 8398: 8394: 8391: 8382: 8380: 8359: 8355: 8351: 8345: 8341: 8337: 8333: 8330: 8326: 8298: 8294: 8290: 8284: 8280: 8276: 8272: 8269: 8265: 8237: 8233: 8229: 8223: 8219: 8215: 8211: 8208: 8204: 8179: 8174: 8170: 8066: 8049: 8045: 8041: 8036: 8032: 8028: 8023: 8019: 8014: 8005: 7988: 7984: 7980: 7975: 7971: 7967: 7962: 7958: 7953: 7949: 7941: 7931: 7926: 7908: 7901: 7875: 7871: 7867: 7861: 7857: 7853: 7847: 7843: 7814: 7810: 7806: 7800: 7796: 7792: 7786: 7782: 7769: 7753: 7750: 7746: 7742: 7737: 7733: 7729: 7724: 7721: 7717: 7713: 7708: 7704: 7681: 7677: 7671: 7667: 7644: 7641: 7637: 7633: 7628: 7624: 7620: 7615: 7611: 7588: 7584: 7578: 7574: 7564: 7545: 7530: 7526: 7517: 7502: 7498: 7494: 7486: 7478: 7474: 7451: 7447: 7443: 7438: 7434: 7405: 7390: 7386: 7377: 7362: 7358: 7354: 7346: 7331: 7327: 7318: 7303: 7299: 7289: 7285: 7280: 7272: 7262: 7256: 7238: 7230: 7226: 7216: 7197: 7193: 7162: 7158: 7127: 7112: 7108: 7099: 7084: 7080: 7076: 7068: 7058: 7053: 7040: 7018: 7014: 6991: 6987: 6961: 6957: 6926: 6922: 6891: 6887: 6873: 6869: 6860: 6854: 6825: 6821: 6814: 6810: 6806: 6803: 6797: 6792: 6787: 6774: 6771: 6767: 6762: 6759: 6754: 6750: 6727: 6723: 6719: 6714: 6710: 6706: 6699: 6695: 6688: 6684: 6680: 6677: 6671: 6664: 6660: 6653: 6649: 6645: 6642: 6636: 6631: 6626: 6613: 6610: 6606: 6601: 6596: 6591: 6578: 6575: 6571: 6566: 6563: 6558: 6554: 6541: 6535: 6512: 6502: 6497: 6478: 6474: 6470: 6464: 6460: 6457: 6447: 6430: 6426: 6419: 6415: 6411: 6408: 6402: 6395: 6391: 6384: 6380: 6376: 6373: 6367: 6362: 6357: 6344: 6341: 6337: 6332: 6327: 6322: 6309: 6306: 6302: 6297: 6294: 6289: 6285: 6276: 6273: 6259: 6256: 6252: 6247: 6243: 6239: 6236: 6228: 6223: 6210: 6197: 6187: 6182: 6163: 6159: 6155: 6149: 6142: 6129: 6125: 6121: 6118: 6112: 6105: 6092: 6088: 6084: 6081: 6075: 6070: 6065: 6052: 6049: 6045: 6040: 6035: 6030: 6017: 6014: 6010: 6005: 6002: 5999: 5991: 5983: 5964: 5953: 5948: 5933: 5929: 5925: 5922: 5914: 5903: 5898: 5883: 5879: 5870: 5854: 5851: 5848: 5845: 5842: 5839: 5836: 5833: 5829: 5824: 5819: 5804: 5793: 5788: 5773: 5769: 5765: 5760: 5745: 5724: 5713: 5708: 5693: 5689: 5685: 5677: 5666: 5661: 5646: 5642: 5633: 5615: 5610: 5595: 5584: 5579: 5564: 5560: 5556: 5543: 5539: 5526: 5518: 5507: 5502: 5487: 5484: 5474: 5471: 5463: 5452: 5447: 5432: 5429: 5414: 5410: 5405: 5402: 5398: 5394: 5356: 5351: 5345: 5340: 5333: 5328: 5322: 5314: 5310: 5305: 5300: 5296: 5291: 5286: 5280: 5275: 5268: 5263: 5257: 5249: 5245: 5240: 5235: 5231: 5226: 5221: 5215: 5212: 5207: 5200: 5195: 5189: 5181: 5177: 5172: 5167: 5163: 5137: 5133: 5129: 5124: 5120: 5116: 5111: 5107: 5095: 5090: 5073: 5065: 5060: 5054: 5049: 5042: 5037: 5031: 5026: 5021: 5016: 5013: 5001: 4993: 4988: 4982: 4977: 4970: 4965: 4959: 4954: 4949: 4944: 4929: 4919: 4907: 4903: 4898: 4893: 4887: 4882: 4875: 4870: 4864: 4856: 4852: 4847: 4842: 4837: 4817: 4815: 4814: 4813:triplet state 4797: 4794: 4791: 4764: 4752: 4748: 4743: 4738: 4732: 4727: 4724: 4717: 4712: 4706: 4698: 4694: 4689: 4684: 4679: 4664: 4663: 4662:singlet state 4646: 4643: 4640: 4631: 4615: 4610: 4595: 4584: 4579: 4564: 4559: 4555: 4549: 4546: 4542: 4538: 4508: 4497: 4492: 4477: 4472: 4468: 4445: 4440: 4424: 4420: 4405: 4393: 4381: 4367: 4355: 4348: 4343: 4330: 4314: 4306: 4296: 4288: 4263: 4260: 4255: 4243: 4240: 4236: 4225: 4215: 4210: 4200: 4197: 4192: 4189: 4185: 4161: 4154: 4151: 4148: 4145: 4120: 4109: 4104: 4089: 4086: 4082: 4073: 4069: 4051: 4033: 4017: 4012: 3994: 3956: 3940: 3934: 3893: 3877: 3871: 3845: 3831: 3828: 3825: 3802: 3799: 3796: 3793: 3780: 3762: 3752: 3746: 3733: 3730: 3727: 3719: 3709: 3704: 3691: 3668: 3641: 3633: 3630: 3627: 3624: 3621: 3618: 3615: 3612: 3608: 3597: 3570: 3562: 3559: 3556: 3553: 3550: 3547: 3544: 3540: 3532: 3524: 3495: 3464: 3460: 3455: 3447: 3444: 3441: 3438: 3435: 3432: 3429: 3425: 3417: 3403: 3385: 3375: 3369: 3356: 3353: 3345: 3335: 3330: 3317: 3273: 3242: 3238: 3233: 3225: 3222: 3219: 3216: 3213: 3210: 3207: 3203: 3188: 3186: 3185: 3184:triplet state 3180: 3179: 3178:singlet state 3160: 3150: 3146: 3142: 3137: 3133: 3126: 3123: 3103: 3100: 3097: 3094: 3091: 3088: 3080: 3079: 3078:triplet state 3062: 3059: 3056: 3036: 3033: 3030: 3027: 3024: 3021: 3013: 3012: 3011:singlet state 2995: 2992: 2989: 2980: 2964: 2960: 2954: 2951: 2948: 2945: 2941: 2920: 2917: 2914: 2911: 2908: 2905: 2897: 2894: 2891: 2883: 2880: 2860: 2840: 2833:, total spin 2820: 2797: 2794: 2791: 2788: 2779: 2776: 2773: 2770: 2758: 2745: 2737: 2733: 2729: 2726: 2723: 2718: 2714: 2710: 2707: 2704: 2701: 2691: 2688: 2685: 2681: 2677: 2669: 2665: 2661: 2658: 2655: 2650: 2646: 2642: 2639: 2636: 2633: 2625: 2617: 2601: 2597: 2574: 2570: 2547: 2543: 2520: 2516: 2506: 2492: 2472: 2450: 2446: 2423: 2419: 2396: 2392: 2369: 2365: 2354: 2307: 2303: 2289: 2285: 2254: 2250: 2219: 2215: 2184: 2180: 2166: 2162: 2131: 2127: 2096: 2092: 2060: 2056: 2045: 2042: 2038: 2032: 2028: 2024: 2016: 2012: 1986: 1978: 1974: 1965: 1962: 1954: 1950: 1941: 1932: 1919: 1911: 1907: 1893: 1889: 1880: 1875: 1872: 1868: 1862: 1859: 1855: 1851: 1843: 1839: 1825: 1821: 1810: 1807: 1803: 1797: 1794: 1790: 1786: 1783: 1775: 1771: 1754: 1750: 1741: 1733: 1730: 1726: 1720: 1717: 1713: 1709: 1701: 1697: 1683: 1679: 1670: 1665: 1662: 1658: 1652: 1649: 1645: 1641: 1627: 1619: 1600: 1596: 1565: 1561: 1530: 1526: 1512: 1508: 1497: 1494: 1490: 1484: 1481: 1477: 1473: 1452: 1439: 1426: 1416: 1411: 1392: 1388: 1384: 1378: 1371: 1358: 1354: 1350: 1347: 1341: 1334: 1321: 1317: 1313: 1310: 1304: 1299: 1294: 1281: 1278: 1274: 1269: 1264: 1259: 1246: 1243: 1239: 1234: 1231: 1228: 1220: 1202: 1198: 1189: 1182: 1178: 1167: 1162: 1158: 1135: 1132: 1129: 1106: 1103: 1083: 1075: 1057: 1046: 1041: 1002: 992: 987: 972: 967: 963: 940: 911: 881: 878: 875: 870: 867: 861: 858: 849: 831: 827: 821: 817: 813: 810: 804: 800: 794: 787: 783: 774: 767: 763: 752: 747: 743: 737: 733: 724: 720: 714: 710: 706: 703: 696: 692: 688: 682: 677: 670: 666: 654: 651: 645: 641: 635: 631: 625: 622: 619: 616: 613: 609: 605: 597: 586: 581: 568: 560: 556: 547: 538: 536: 532: 528: 524: 520: 516: 512: 509:. Unlike for 508: 504: 500: 497:bound by the 496: 495:two electrons 492: 488: 484: 471: 464: 459: 442: 436: 431: 426: 423: 420: 416: 415: 412:Pharmacology 410: 406: 398: 393: 387: 386: 381: 377: 375: 374:Boiling point 372: 371: 367: 364: 363: 353: 351: 348: 347: 341: 338: 334: 333: 328: 322: 321: 318: 311: 297: 296: 293: 286: 282: 280: 277: 276: 269: 265: 264: 262: 260: 257: 256: 249: 248: 246: 244: 241: 240: 233: 229: 228: 226: 220: 216: 215: 211: 207: 205: 202: 201: 194: 190: 189: 187: 185: 182: 181: 177: 174: 170: 169: 162: 161: 159: 157: 152: 151: 144: 140: 139: 137: 135: 132: 131: 124: 120: 119: 117: 115: 112: 111: 104: 100: 99: 97: 93: 88: 87: 80: 76: 75: 73: 70: 66: 65: 60: 52: 48: 43: 35: 30: 22: 13163: 13159: 13153: 13098: 13093: 13082: 13033: 13029: 13019: 12984: 12980:Phys. Rev. A 12978: 12965: 12924: 12920: 12914: 12906: 12901: 12868: 12864: 12858: 12817: 12813: 12807: 12774: 12770: 12764: 12755: 12749: 12740: 12734: 12717: 12674: 12667: 12650: 12644: 12625: 12619: 12568: 12549: 12536: 12527: 12488:Lithium atom 12460:(26) Ry 12447:Atomic units 12434:(25) eV 12412:(25) eV 12398: 11888: 11885: 11811: 11807: 11803: 11685: 11437: 11424:relativistic 11416:(25) eV 11406: 11397: 11394: 11311: 11171: 11083: 11054: 10895: 10891: 10889: 10750: 10747: 10577: 10132: 10125: 10086: 10078: 10071: 9749: 9743: 9626: 9622: 9581: 9577: 9391: 9382:(25) eV 9338: 8973: 8891: 8658: 8649:ground state 8642: 8639: 8432: 8383: 7770: 7603:state (with 7565: 7217: 6539: 6536: 6448: 6277: 6274: 6224: 5992: 5989: 5868: 5743: 5631: 5541: 5540: 5412: 5406: 5399:), the four 5091: 4818: 4811: 4660: 4632: 4425: 4421: 4331: 3846: 3781: 3404: 3189: 3182: 3176: 3076: 3009: 2981: 2759: 2618: 2507: 2355: 1933: 1620: 1453: 1221: 1023: 850: 552: 541:Introduction 531:wavefunction 527:ground state 507:strong force 482: 480: 396: 243:RTECS number 62:Identifiers 27:Helium atom 12423:(2) eV 6227:Hamiltonian 5744:orthohelium 3049:state) and 559:Hamiltonian 529:energy and 483:helium atom 365:Appearance 330:Properties 300:InChI=1S/He 123:CHEBI:33681 13219:Categories 12520:References 12445:(13)  5632:symmetric 5542:Parahelium 350:Molar mass 268:206GF3GB41 134:ChemSpider 90:3D model ( 69:CAS Number 13173:1004.5110 13058:1050-2947 12949:1050-2947 12893:0031-8949 12842:0031-9007 12799:0009-2614 12294:ψ 12255:ψ 12231:− 12163:ψ 12135:ψ 12131:∫ 12128:∫ 12039:− 11959:ψ 11914:ψ 11905:∫ 11902:∫ 11858:Δ 11825:Δ 11787:± 11766:Δ 11733:Δ 11651:− 11564:− 11529:− 11508:∇ 11494:− 11473:∇ 11459:− 11373:− 11295:∼ 11205:− 11114:− 11103:⟩ 11097:⟨ 10986:ε 10982:π 10953:− 10912:⟩ 10906:⟨ 10890:Treating 10834:− 10813:π 10761:ψ 10726:− 10711:− 10685:− 10653:ϵ 10649:π 10592:⟩ 10586:⟨ 10498:− 10435:− 10425:∫ 10399:π 10372:ε 10368:π 10326:⟩ 10310:⟨ 10288:⟩ 10282:⟨ 10221:− 10200:π 10148:ψ 10017:− 9990:π 9929:ψ 9849:− 9792:− 9777:− 9697:− 9669:− 9654:− 9605:¯ 9545:− 9510:− 9488:− 9453:− 9415:¯ 9353:− 9350:≈ 9186:− 9158:− 9096:π 9079:∫ 9076:∫ 9058:Δ 9017:− 8951:− 8913:− 8828:− 8802:π 8749:ψ 8711:ψ 8668:ψ 8525:− 8171:σ 8150:⟩ 8147:↑ 8139:⟩ 8136:↓ 8111:⟩ 8108:↓ 8100:⟩ 8097:↑ 8033:ℓ 8015:ψ 7972:ℓ 7954:ψ 7902:ψ 7747:ψ 7734:ψ 7718:ψ 7705:ψ 7638:ψ 7625:ψ 7612:ψ 7527:ψ 7499:ψ 7475:ψ 7448:ψ 7435:ψ 7387:ψ 7359:ψ 7355:± 7328:ψ 7300:ψ 7231:± 7227:ψ 7203:⟩ 7194:ψ 7168:⟩ 7159:ψ 7109:ψ 7081:ψ 7041:ψ 6967:⟩ 6958:ψ 6932:⟩ 6923:ψ 6897:⟩ 6888:ψ 6879:⟩ 6870:ψ 6858:⟩ 6855:ψ 6798:− 6763:− 6672:− 6637:− 6602:− 6567:− 6503:− 6403:− 6368:− 6333:− 6298:− 6188:− 6113:− 6076:− 6041:− 6006:− 5934:− 5930:ψ 5926:− 5884:− 5880:ψ 5840:− 5815:σ 5774:− 5770:ψ 5756:ϕ 5690:ψ 5643:ψ 5606:σ 5561:ψ 5553:ϕ 5480:ψ 5475:− 5425:ψ 5378:ψ 5297:σ 5232:σ 5213:− 5164:σ 5134:σ 5121:σ 5108:σ 5014:− 5009:σ 4940:σ 4833:σ 4765:− 4725:− 4675:σ 4606:σ 4556:ϕ 4543:∑ 4535:ψ 4469:ϕ 4436:σ 4394:ψ 4382:ψ 4368:ψ 4356:ψ 4340:ψ 4311:⟩ 4293:⟩ 4237:ψ 4198:∫ 4186:∑ 4165:↓ 4159:↑ 4083:ψ 4048:⟩ 4044:↑ 4030:⟩ 4026:↓ 4018:≠ 4009:⟩ 4005:↓ 3991:⟩ 3987:↑ 3953:⟩ 3949:↓ 3931:⟩ 3927:↑ 3890:⟩ 3886:↓ 3868:⟩ 3864:↑ 3734:ψ 3731:− 3692:ψ 3665:⟩ 3662:↓ 3654:⟩ 3651:↓ 3639:⟩ 3631:− 3609:χ 3594:⟩ 3591:↑ 3583:⟩ 3580:↑ 3568:⟩ 3541:χ 3518:⟩ 3515:↑ 3507:⟩ 3504:↓ 3493:⟩ 3490:↓ 3482:⟩ 3479:↑ 3453:⟩ 3426:χ 3357:ψ 3318:ψ 3296:⟩ 3293:↑ 3285:⟩ 3282:↓ 3274:− 3271:⟩ 3268:↓ 3260:⟩ 3257:↑ 3231:⟩ 3204:χ 2909:… 2895:− 2743:⟩ 2675:⟩ 2397:± 2370:± 2341:⟩ 2338:Φ 2313:⟩ 2304:χ 2295:⟩ 2286:ψ 2260:⟩ 2251:χ 2225:⟩ 2216:ψ 2190:⟩ 2181:χ 2172:⟩ 2163:ψ 2137:⟩ 2128:ψ 2102:⟩ 2093:χ 2066:⟩ 2057:φ 2029:∑ 2022:⟩ 2013:ψ 1984:⟩ 1975:ψ 1960:⟩ 1951:ψ 1917:⟩ 1908:χ 1899:⟩ 1890:φ 1856:∑ 1849:⟩ 1840:χ 1831:⟩ 1822:φ 1791:∑ 1781:⟩ 1772:χ 1760:⟩ 1751:φ 1714:∑ 1707:⟩ 1698:χ 1689:⟩ 1680:φ 1646:∑ 1639:⟩ 1636:Φ 1606:⟩ 1597:χ 1571:⟩ 1562:φ 1536:⟩ 1527:χ 1518:⟩ 1509:φ 1478:∑ 1471:⟩ 1468:Φ 1417:− 1342:− 1305:− 1270:− 1235:− 1194:∇ 1190:⋅ 1174:∇ 1159:ℏ 1130:μ 1110:∞ 993:− 859:μ 818:ε 814:π 779:∇ 775:⋅ 759:∇ 744:ℏ 738:− 711:ε 707:π 683:− 662:∇ 655:μ 642:ℏ 636:− 610:∑ 390:Std molar 279:UN number 250:MH6520000 163:231-168-5 155:EC Number 79:7440-59-7 13198:20867977 13139:cite web 13074:36134307 12850:10058600 12659:25750516 12608:"Helium" 12466:See also 11380: eV 11040:⟩ 11024:⟨ 11016:⟩ 11003:⟨ 10733: eV 9601:′ 9411:′ 9360: eV 8958: eV 6461:′ 6260:′ 5867:with an 1122:we have 511:hydrogen 433:) 419:ATC code 39:Helium-4 13206:2499460 13178:Bibcode 13066:9908396 13038:Bibcode 12989:Bibcode 12957:9903218 12929:Bibcode 12873:Bibcode 12822:Bibcode 12779:Bibcode 12539:. USA: 12427:−79.005 12416:−54.417 12405:−24.587 11420:Pekeris 11409:−79.005 9375:−79.005 5630:with a 5395:, like 517:to the 503:isotope 463:what is 461: ( 427: ( 425:V03AN03 392:entropy 219:PubChem 13235:Helium 13204:  13196:  13105:  13072:  13064:  13056:  12955:  12947:  12891:  12848:  12840:  12797:  12690:  12657:  12632:  12584:  12453:−5.806 12438:−2.903 9741:where 7696:(with 6909:where 4072:spinor 2589:, and 2202:where 1999:where 1548:where 851:where 557:. The 491:helium 485:is an 458:verify 455:  317:SMILES 210:Helium 193:D04420 178:16294 55:Helium 45:Names 21:Helium 13225:Atoms 13202:S2CID 13168:arXiv 13070:S2CID 12975:(PDF) 12611:(PDF) 12436:, or 11757:with: 8954:108.8 8162:from 6742:where 6225:This 1455:that 355:4.002 292:InChI 283:1046 232:23987 143:22423 114:ChEBI 92:JSmol 13194:PMID 13145:link 13131:NIST 13103:ISBN 13062:PMID 13054:ISSN 12953:PMID 12945:ISSN 12889:ISSN 12846:PMID 12838:ISSN 12795:ISSN 12718:NIST 12688:ISBN 12655:OCLC 12630:ISBN 12582:ISBN 12449:a.u. 11426:and 11376:77.5 11298:1.69 11082:and 9356:74.8 8123:and 7832:and 7180:and 7006:and 6944:and 5742:and 2438:and 2384:and 926:and 513:, a 487:atom 259:UNII 204:MeSH 184:KEGG 13186:doi 13164:105 13046:doi 13005:hdl 12997:doi 12937:doi 12907:189 12881:doi 12869:T83 12830:doi 12787:doi 12775:229 12722:doi 12680:doi 12574:doi 12455:771 12440:385 12432:539 12429:154 12418:763 12410:936 12407:387 12403:is 12298:100 12139:100 11918:100 11810:or 11705:100 11414:539 11411:154 10714:109 10089:= 2 10070:If 9631:is 9380:539 9377:154 4526:as 3187:). 430:WHO 400:298 357:602 222:CID 13221:: 13200:. 13192:. 13184:. 13176:. 13162:. 13141:}} 13137:{{ 13117:^ 13068:. 13060:. 13052:. 13044:. 13034:46 13032:. 13028:. 13003:. 12995:. 12985:75 12983:. 12977:. 12951:. 12943:. 12935:. 12925:41 12923:. 12887:. 12879:. 12867:. 12844:. 12836:. 12828:. 12818:74 12816:. 12793:. 12785:. 12773:. 12720:. 12716:. 12702:^ 12686:. 12596:^ 12580:. 12558:^ 12535:. 12462:. 12458:66 12443:83 12421:11 11683:. 11290:16 11287:27 11226:27 11135:27 11087:ee 10729:75 10720:34 10136:ee 9446:12 8430:. 8381:. 7563:. 5982:. 4816:) 4630:. 2979:. 2562:, 2535:, 968:12 832:12 481:A 343:He 13208:. 13188:: 13180:: 13170:: 13147:) 13133:. 13111:. 13076:. 13048:: 13040:: 13013:. 13007:: 12999:: 12991:: 12959:. 12939:: 12931:: 12895:. 12883:: 12875:: 12852:. 12832:: 12824:: 12801:. 12789:: 12781:: 12728:. 12724:: 12696:. 12682:: 12661:. 12638:. 12613:. 12590:. 12576:: 12543:. 12365:2 12360:r 12353:3 12349:d 12343:1 12338:r 12331:3 12327:d 12323:) 12318:2 12313:r 12308:( 12303:* 12290:) 12285:1 12280:r 12275:( 12270:* 12265:m 12262:l 12259:n 12247:| 12241:2 12236:r 12226:1 12221:r 12215:| 12207:2 12203:e 12199:k 12193:) 12188:2 12183:r 12178:( 12173:m 12170:l 12167:n 12159:) 12154:1 12149:r 12144:( 12125:= 12122:J 12101:2 12096:r 12089:3 12085:d 12079:1 12074:r 12067:3 12063:d 12055:| 12049:2 12044:r 12034:1 12029:r 12023:| 12015:2 12011:e 12007:k 11999:2 11994:| 11989:) 11984:2 11979:r 11974:( 11969:m 11966:l 11963:n 11954:| 11948:2 11943:| 11938:) 11933:1 11928:r 11923:( 11909:| 11899:= 11896:I 11868:) 11865:1 11862:( 11835:) 11832:1 11829:( 11790:J 11784:I 11781:= 11776:) 11773:1 11770:( 11743:) 11740:1 11737:( 11729:+ 11724:m 11721:l 11718:n 11714:E 11710:+ 11701:E 11697:= 11694:E 11667:| 11661:2 11656:r 11646:1 11641:r 11635:| 11627:2 11623:e 11619:k 11592:2 11588:r 11581:2 11577:e 11573:Z 11570:k 11557:1 11553:r 11546:2 11542:e 11538:Z 11535:k 11524:2 11517:2 11513:r 11502:2 11499:1 11489:2 11482:1 11478:r 11467:2 11464:1 11456:= 11451:0 11447:H 11401:1 11398:E 11370:= 11365:1 11361:E 11355:6 11350:) 11345:2 11342:3 11337:( 11330:2 11327:1 11282:= 11279:Z 11260:0 11257:= 11253:) 11247:1 11243:E 11238:] 11234:Z 11229:4 11221:+ 11216:2 11212:Z 11208:2 11201:[ 11196:( 11189:Z 11186:d 11182:d 11156:1 11152:E 11147:] 11143:Z 11138:4 11130:+ 11125:2 11121:Z 11117:2 11110:[ 11106:= 11100:H 11084:V 11068:r 11065:1 11035:e 11032:e 11028:V 11020:+ 11011:r 11008:1 10998:) 10990:0 10979:4 10973:2 10969:e 10963:( 10959:) 10956:2 10950:Z 10947:( 10944:2 10941:+ 10936:1 10932:E 10926:2 10922:Z 10918:2 10915:= 10909:H 10896:H 10892:Z 10874:a 10870:/ 10866:) 10861:2 10857:r 10853:+ 10848:1 10844:r 10840:( 10837:Z 10830:e 10821:3 10817:a 10807:3 10803:Z 10797:= 10794:) 10789:2 10784:r 10779:, 10774:1 10769:r 10764:( 10751:Z 10723:= 10717:+ 10708:= 10703:1 10699:E 10693:2 10690:5 10680:1 10676:E 10672:8 10669:= 10665:) 10657:0 10646:4 10640:2 10636:e 10630:( 10623:a 10620:4 10616:5 10611:+ 10606:1 10602:E 10598:8 10595:= 10589:H 10562:2 10557:r 10550:3 10546:d 10539:1 10534:r 10527:3 10523:d 10514:| 10508:2 10503:r 10493:1 10488:r 10482:| 10475:a 10471:/ 10467:) 10462:2 10458:r 10454:+ 10449:1 10445:r 10441:( 10438:4 10431:e 10420:2 10415:) 10407:3 10403:a 10395:8 10390:( 10384:) 10376:0 10365:4 10359:2 10355:e 10349:( 10345:+ 10340:1 10336:E 10332:8 10329:= 10321:e 10318:e 10314:V 10307:+ 10302:1 10298:E 10294:8 10291:= 10285:H 10261:a 10257:/ 10253:) 10248:2 10244:r 10240:+ 10235:1 10231:r 10227:( 10224:2 10217:e 10208:3 10204:a 10196:8 10191:= 10188:) 10183:2 10178:r 10172:, 10167:1 10162:r 10157:( 10152:0 10133:V 10104:3 10101:1 10087:Z 10082:0 10079:E 10075:e 10072:Z 10056:) 10051:2 10047:r 10043:+ 10038:1 10034:r 10030:( 10025:e 10021:Z 10013:e 10003:3 9998:0 9994:a 9984:3 9979:e 9975:Z 9968:= 9965:) 9960:2 9956:r 9952:, 9946:1 9942:r 9938:( 9933:0 9903:2 9899:n 9893:0 9889:a 9885:2 9878:2 9874:e 9868:2 9863:e 9859:Z 9855:k 9846:= 9838:2 9834:n 9828:0 9824:a 9820:2 9813:2 9809:e 9803:2 9799:) 9795:S 9789:Z 9786:( 9783:k 9774:= 9769:0 9765:E 9753:e 9750:Z 9744:S 9727:r 9721:2 9717:e 9711:e 9707:Z 9703:k 9694:= 9689:r 9683:2 9679:e 9675:) 9672:S 9666:Z 9663:( 9660:k 9651:= 9648:) 9645:r 9642:( 9639:V 9629:) 9627:r 9625:( 9623:V 9598:H 9584:) 9582:r 9580:( 9578:V 9564:) 9559:2 9555:r 9551:( 9548:V 9538:2 9534:r 9527:2 9523:e 9519:Z 9516:k 9507:) 9502:1 9498:r 9494:( 9491:V 9481:1 9477:r 9470:2 9466:e 9462:Z 9459:k 9442:r 9435:2 9431:e 9427:k 9421:= 9408:H 9394:Z 9347:E 9321:0 9317:a 9310:2 9306:e 9302:k 9294:4 9291:5 9286:= 9281:2 9276:r 9269:3 9265:d 9259:1 9254:r 9247:3 9243:d 9233:0 9229:a 9224:) 9219:2 9215:r 9211:+ 9206:1 9202:r 9198:( 9195:Z 9192:2 9182:e 9174:| 9168:2 9163:r 9153:1 9148:r 9142:| 9134:2 9130:e 9126:k 9115:6 9110:0 9106:a 9100:2 9089:6 9085:Z 9073:= 9068:) 9065:1 9062:( 9049:: 9033:| 9027:2 9022:r 9012:1 9007:r 9001:| 8993:2 8989:e 8985:k 8948:= 8941:0 8937:a 8930:2 8926:e 8922:k 8916:4 8910:= 8905:0 8901:E 8872:0 8868:a 8863:) 8858:2 8854:r 8850:+ 8845:1 8841:r 8837:( 8834:Z 8824:e 8815:3 8810:0 8806:a 8796:3 8792:Z 8786:= 8783:) 8778:2 8774:r 8770:( 8765:0 8762:, 8759:0 8756:, 8753:1 8745:) 8740:1 8736:r 8732:( 8727:0 8724:, 8721:0 8718:, 8715:1 8707:= 8704:) 8699:2 8695:r 8691:, 8685:1 8681:r 8677:( 8672:0 8625:] 8617:2 8612:2 8608:n 8604:1 8599:+ 8592:2 8587:1 8583:n 8579:1 8573:[ 8564:0 8560:a 8556:2 8549:2 8545:e 8539:2 8535:Z 8531:k 8522:= 8515:2 8511:n 8506:E 8502:+ 8495:1 8491:n 8486:E 8482:= 8477:) 8474:0 8471:( 8464:2 8460:n 8456:, 8451:1 8447:n 8442:E 8416:b 8412:E 8408:+ 8403:a 8399:E 8395:= 8392:E 8365:) 8360:s 8356:m 8352:, 8346:l 8342:m 8338:, 8334:l 8331:, 8327:n 8324:( 8304:) 8299:s 8295:m 8291:, 8285:l 8281:m 8277:, 8273:l 8270:, 8266:n 8263:( 8243:) 8238:s 8234:m 8230:, 8224:l 8220:m 8216:, 8212:l 8209:, 8205:n 8202:( 8180:0 8175:0 8143:| 8132:| 8104:| 8093:| 8072:) 8067:2 8062:r 8057:( 8050:2 8046:m 8042:, 8037:2 8029:, 8024:2 8020:n 8011:) 8006:1 8001:r 7996:( 7989:1 7985:m 7981:, 7976:1 7968:, 7963:1 7959:n 7950:= 7947:) 7942:2 7937:r 7932:, 7927:1 7922:r 7917:( 7912:) 7909:0 7906:( 7881:) 7876:2 7872:m 7868:, 7862:2 7858:l 7854:, 7848:2 7844:n 7840:( 7820:) 7815:1 7811:m 7807:, 7801:1 7797:l 7793:, 7787:1 7783:n 7779:( 7754:s 7751:2 7743:= 7738:b 7730:, 7725:s 7722:1 7714:= 7709:a 7682:1 7678:S 7672:3 7668:2 7645:s 7642:1 7634:= 7629:b 7621:= 7616:a 7589:1 7585:S 7579:3 7575:1 7551:) 7546:2 7541:r 7536:( 7531:a 7523:) 7518:1 7513:r 7508:( 7503:a 7495:= 7490:) 7487:0 7484:( 7479:+ 7452:b 7444:= 7439:a 7414:) 7411:) 7406:1 7401:r 7396:( 7391:b 7383:) 7378:2 7373:r 7368:( 7363:a 7352:) 7347:2 7342:r 7337:( 7332:b 7324:) 7319:1 7314:r 7309:( 7304:a 7296:( 7290:2 7286:1 7281:= 7278:) 7273:2 7268:r 7263:, 7257:1 7252:r 7247:( 7242:) 7239:0 7236:( 7198:2 7189:| 7163:1 7154:| 7133:) 7128:2 7123:r 7118:( 7113:b 7105:) 7100:1 7095:r 7090:( 7085:a 7077:= 7074:) 7069:2 7064:r 7059:, 7054:1 7049:r 7044:( 7019:2 7015:H 6992:1 6988:H 6962:2 6953:| 6927:1 6918:| 6892:2 6883:| 6874:1 6865:| 6861:= 6851:| 6826:i 6822:r 6815:2 6811:e 6807:Z 6804:k 6793:2 6788:i 6783:p 6775:m 6772:2 6768:1 6760:= 6755:i 6751:H 6728:2 6724:H 6720:+ 6715:1 6711:H 6707:= 6700:2 6696:r 6689:2 6685:e 6681:Z 6678:k 6665:1 6661:r 6654:2 6650:e 6646:Z 6643:k 6632:2 6627:2 6622:p 6614:m 6611:2 6607:1 6597:2 6592:1 6587:p 6579:m 6576:2 6572:1 6564:= 6559:0 6555:H 6543:0 6540:H 6519:| 6513:2 6508:r 6498:1 6493:r 6487:| 6479:2 6475:e 6471:k 6465:= 6458:H 6431:2 6427:r 6420:2 6416:e 6412:Z 6409:k 6396:1 6392:r 6385:2 6381:e 6377:Z 6374:k 6363:2 6358:2 6353:p 6345:m 6342:2 6338:1 6328:2 6323:1 6318:p 6310:m 6307:2 6303:1 6295:= 6290:0 6286:H 6257:H 6253:+ 6248:0 6244:H 6240:= 6237:H 6211:. 6204:| 6198:2 6193:r 6183:1 6178:r 6172:| 6164:2 6160:e 6156:k 6150:+ 6143:2 6138:r 6130:2 6126:e 6122:Z 6119:k 6106:1 6101:r 6093:2 6089:e 6085:Z 6082:k 6071:2 6066:2 6061:p 6053:m 6050:2 6046:1 6036:2 6031:1 6026:p 6018:m 6015:2 6011:1 6003:= 6000:H 5970:) 5965:1 5960:r 5954:, 5949:2 5944:r 5939:( 5923:= 5920:) 5915:2 5910:r 5904:, 5899:1 5894:r 5889:( 5855:1 5852:, 5849:0 5846:, 5843:1 5837:= 5834:m 5830:, 5825:1 5820:m 5810:) 5805:2 5800:r 5794:, 5789:1 5784:r 5779:( 5766:= 5761:m 5730:) 5725:1 5720:r 5714:, 5709:2 5704:r 5699:( 5694:+ 5686:= 5683:) 5678:2 5673:r 5667:, 5662:1 5657:r 5652:( 5647:+ 5616:0 5611:0 5601:) 5596:2 5591:r 5585:, 5580:1 5575:r 5570:( 5565:+ 5557:= 5527:. 5524:) 5519:1 5514:r 5508:, 5503:2 5498:r 5493:( 5488:i 5485:j 5472:= 5469:) 5464:2 5459:r 5453:, 5448:1 5443:r 5438:( 5433:j 5430:i 5357:. 5352:) 5346:0 5341:1 5334:1 5329:0 5323:( 5315:2 5311:1 5306:= 5301:z 5292:, 5287:) 5281:1 5276:0 5269:0 5264:1 5258:( 5250:2 5246:i 5241:= 5236:y 5227:, 5222:) 5216:1 5208:0 5201:0 5196:1 5190:( 5182:2 5178:1 5173:= 5168:x 5143:) 5138:z 5130:, 5125:y 5117:, 5112:x 5104:( 5074:. 5066:= 5061:) 5055:1 5050:0 5043:0 5038:0 5032:( 5027:= 5022:1 5017:1 5002:; 4994:= 4989:) 4983:0 4978:0 4971:0 4966:1 4960:( 4955:= 4950:1 4945:1 4930:; 4926:) 4920:+ 4914:( 4908:2 4904:1 4899:= 4894:) 4888:0 4883:1 4876:1 4871:0 4865:( 4857:2 4853:1 4848:= 4843:1 4838:0 4798:1 4795:= 4792:S 4771:) 4759:( 4753:2 4749:1 4744:= 4739:) 4733:0 4728:1 4718:1 4713:0 4707:( 4699:2 4695:1 4690:= 4685:0 4680:0 4665:) 4647:0 4644:= 4641:S 4616:i 4611:k 4601:) 4596:2 4591:r 4585:, 4580:1 4575:r 4570:( 4565:k 4560:i 4550:k 4547:i 4539:= 4514:) 4509:2 4504:r 4498:, 4493:1 4488:r 4483:( 4478:k 4473:i 4446:i 4441:k 4406:) 4349:( 4344:= 4315:2 4307:j 4303:| 4297:1 4289:i 4285:| 4264:1 4261:= 4256:2 4251:| 4244:j 4241:i 4232:| 4226:2 4221:r 4216:d 4211:1 4206:r 4201:d 4193:j 4190:i 4162:, 4155:= 4152:j 4149:, 4146:i 4126:) 4121:2 4116:r 4110:, 4105:1 4100:r 4095:( 4090:j 4087:i 4052:2 4040:| 4034:1 4022:| 4013:2 4001:| 3995:1 3983:| 3962:} 3957:2 3945:| 3941:, 3935:2 3923:| 3919:{ 3899:} 3894:1 3882:| 3878:, 3872:1 3860:| 3856:{ 3832:0 3829:= 3826:l 3806:) 3803:1 3800:+ 3797:l 3794:2 3791:( 3768:) 3763:1 3758:r 3753:, 3747:2 3742:r 3737:( 3728:= 3725:) 3720:2 3715:r 3710:, 3705:1 3700:r 3695:( 3669:. 3658:| 3647:| 3642:= 3634:1 3628:= 3625:m 3622:, 3619:1 3616:= 3613:s 3604:| 3598:; 3587:| 3576:| 3571:= 3563:1 3560:= 3557:m 3554:, 3551:1 3548:= 3545:s 3536:| 3525:; 3521:) 3511:| 3500:| 3496:+ 3486:| 3475:| 3471:( 3465:2 3461:1 3456:= 3448:0 3445:= 3442:m 3439:, 3436:1 3433:= 3430:s 3421:| 3391:) 3386:1 3381:r 3376:, 3370:2 3365:r 3360:( 3354:= 3351:) 3346:2 3341:r 3336:, 3331:1 3326:r 3321:( 3299:) 3289:| 3278:| 3264:| 3253:| 3249:( 3243:2 3239:1 3234:= 3226:0 3223:= 3220:m 3217:, 3214:0 3211:= 3208:s 3199:| 3161:2 3157:) 3151:2 3147:S 3143:+ 3138:1 3134:S 3130:( 3127:= 3124:S 3104:3 3101:= 3098:1 3095:+ 3092:s 3089:2 3063:1 3060:= 3057:S 3037:1 3034:= 3031:1 3028:+ 3025:s 3022:2 2996:0 2993:= 2990:S 2965:J 2961:L 2955:1 2952:+ 2949:S 2946:2 2942:n 2921:S 2918:+ 2915:L 2912:, 2906:, 2902:| 2898:S 2892:L 2888:| 2884:= 2881:J 2861:L 2841:S 2821:n 2801:) 2798:1 2795:+ 2792:s 2789:2 2786:( 2783:) 2780:1 2777:+ 2774:l 2771:2 2768:( 2746:, 2738:s 2734:m 2730:, 2727:S 2724:, 2719:l 2715:m 2711:, 2708:L 2705:, 2702:N 2698:| 2692:s 2689:l 2686:n 2682:E 2678:= 2670:s 2666:m 2662:, 2659:S 2656:, 2651:l 2647:m 2643:, 2640:L 2637:, 2634:N 2630:| 2626:H 2602:z 2598:S 2575:2 2571:S 2548:z 2544:L 2521:2 2517:L 2493:s 2473:s 2451:s 2447:m 2424:l 2420:m 2393:L 2366:S 2334:| 2308:i 2299:| 2290:i 2281:| 2255:i 2246:| 2220:i 2211:| 2185:i 2176:| 2167:i 2158:| 2132:i 2123:| 2097:i 2088:| 2061:i 2052:| 2046:j 2043:i 2039:c 2033:i 2025:= 2017:j 2008:| 1987:, 1979:j 1970:| 1966:E 1963:= 1955:j 1946:| 1942:H 1920:, 1912:j 1903:| 1894:i 1885:| 1881:E 1876:j 1873:i 1869:c 1863:j 1860:i 1852:= 1844:j 1835:| 1826:i 1817:| 1811:j 1808:i 1804:c 1798:j 1795:i 1787:E 1784:= 1776:j 1767:| 1763:) 1755:i 1746:| 1742:H 1739:( 1734:j 1731:i 1727:c 1721:j 1718:i 1710:= 1702:j 1693:| 1684:i 1675:| 1671:H 1666:j 1663:i 1659:c 1653:j 1650:i 1642:= 1632:| 1628:H 1601:i 1592:| 1566:i 1557:| 1531:j 1522:| 1513:i 1504:| 1498:j 1495:i 1491:c 1485:j 1482:i 1474:= 1464:| 1440:. 1433:| 1427:2 1422:r 1412:1 1407:r 1401:| 1393:2 1389:e 1385:k 1379:+ 1372:2 1367:r 1359:2 1355:e 1351:Z 1348:k 1335:1 1330:r 1322:2 1318:e 1314:Z 1311:k 1300:2 1295:2 1290:p 1282:m 1279:2 1275:1 1265:2 1260:1 1255:p 1247:m 1244:2 1240:1 1232:= 1229:H 1203:2 1199:r 1183:1 1179:r 1168:M 1163:2 1136:m 1133:= 1107:= 1104:M 1084:Z 1063:) 1058:2 1053:r 1047:, 1042:1 1037:r 1032:( 1009:| 1003:2 998:r 988:1 983:r 977:| 973:= 964:r 941:2 936:r 912:1 907:r 882:M 879:+ 876:m 871:M 868:m 862:= 828:r 822:0 811:4 805:2 801:e 795:+ 788:2 784:r 768:1 764:r 753:M 748:2 734:) 725:i 721:r 715:0 704:4 697:2 693:e 689:Z 678:2 671:i 667:r 652:2 646:2 632:( 626:2 623:, 620:1 617:= 614:i 606:= 603:) 598:2 593:r 587:, 582:1 577:r 572:( 569:H 453:N 402:) 397:S 395:( 94:) 23:.

Index

Helium

Systematic IUPAC name
CAS Number
7440-59-7
JSmol
Interactive image
ChEBI
CHEBI:33681
ChemSpider
22423
EC Number
Gmelin Reference
KEGG
D04420
MeSH
Helium
PubChem
23987
RTECS number
UNII
206GF3GB41
UN number
InChI
SMILES
Chemical formula
Molar mass
Boiling point
Std molar
entropy

ATC code

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