25:
256:(HSAB) was proposed in 1963 in an attempt to unify the theories of reactivity in inorganic and organic chemistry. In this theory 'Hard' applies to species that are small, have high charge states, and are weakly
260:. 'Soft' applies to species that are large, have low charge states and are strongly polarizable. Acids and bases interact, and the most stable interactions are hard–hard and soft–soft.
502:
507:
271:, an approximate method in molecular quantum mechanics. This concept of "absolute hardness" was later connected with the concept of (absolute)
229:
to a more quantitative science. With another
Northwestern colleague, Arthur Atwater Frost, Pearson wrote in 1961 another classic text,
207:
176:
217:, his colleague at Northwestern wrote the influential monograph "Mechanisms of Inorganic Reactions", which integrated concepts from
522:
517:
492:
319:
497:
512:
246:
238:
68:
46:
39:
527:
210:(UCSB). He retired in 1989 but remained active in research in theoretical inorganic chemistry until his death.
429:
253:
196:
147:
370:
Mechanisms of inorganic reactions - A study of metal complexes in solution (Basolo, Fred; Pearson, Ralph G.)
291:
267:, he refined the HSAB theory into a quantitative method by calculating values of “absolute hardness” using
222:
427:
Pearson, R. G. (1988). "Absolute electronegativity and hardness: application to inorganic chemistry".
284:
268:
33:
203:
136:
226:
50:
487:
482:
8:
218:
192:
164:
446:
354:
206:, and taught chemistry at Northwestern faculty from 1946 until 1976, when he moved to
401:
272:
242:
234:
450:
438:
409:
381:
350:
315:
467:
257:
476:
264:
214:
442:
413:
385:
112:
231:
Kinetics and
Mechanism: A Study of Homogeneous Chemical Reactions
108:
316:"Ralph G. Pearson - Department of Chemistry - UC Santa Barbara"
191:(January 12, 1919 – October 12, 2022) was an American physical
241:). A subsequent edition was with John W. Moore as co-author (
399:
Pearson, Ralph G. (1963). "Hard and Soft Acids and Bases".
287:
503:
Members of the United States
National Academy of Sciences
202:
He received his Ph.D. in physical chemistry in 1943 from
341:
Ford, P. C. (1999). "Interview with Ralph G. Pearson".
275:. Pearson died on October 12, 2022, at the age of 103.
468:
398:
195:best known for the development of the concept of
474:
508:University of California, Santa Barbara faculty
426:
367:
340:
208:University of California at Santa Barbara
177:University of California at Santa Barbara
69:Learn how and when to remove this message
32:This article includes a list of general
368:Murmann, R. K. (1968). "Book review of
475:
320:University of California Santa Barbara
310:
308:
225:and signaled a shift from descriptive
148:hard and soft acid base theory (HSAB)
18:
305:
13:
38:it lacks sufficient corresponding
14:
539:
461:
23:
523:Northwestern University faculty
518:Northwestern University alumni
493:21st-century American chemists
420:
392:
361:
343:Coordination Chemistry Reviews
334:
263:In 1983 in collaboration with
1:
355:10.1016/S0010-8545(98)00223-9
298:
254:hard and soft acids and bases
197:hard and soft acids and bases
292:National Academy of Sciences
16:American chemist (1919–2022)
7:
498:American inorganic chemists
10:
544:
322:Chemistry and Biochemistry
278:
223:physical organic chemistry
513:American men centenarians
285:American Chemical Society
269:density functional theory
182:
170:
160:
153:
142:
132:
120:
90:
83:
252:A qualitative theory of
528:Scientists from Chicago
204:Northwestern University
174:Northwestern University
137:Northwestern University
53:more precise citations.
227:coordination chemistry
189:Ralph Gottfrid Pearson
95:Ralph Gottfrid Pearson
213:In 1958 Pearson and
443:10.1021/ic00277a030
430:Inorganic Chemistry
414:10.1021/ja00905a001
219:ligand field theory
165:Inorganic chemistry
386:10.1021/ed045pA146
408:(22): 3533–3539.
402:J. Am. Chem. Soc.
273:electronegativity
193:inorganic chemist
186:
185:
155:Scientific career
79:
78:
71:
535:
455:
454:
424:
418:
417:
396:
390:
389:
380:(2): A146–A148.
365:
359:
358:
338:
332:
331:
329:
327:
312:
127:
124:October 12, 2022
105:January 12, 1919
104:
102:
81:
80:
74:
67:
63:
60:
54:
49:this article by
40:inline citations
27:
26:
19:
543:
542:
538:
537:
536:
534:
533:
532:
473:
472:
464:
459:
458:
425:
421:
397:
393:
366:
362:
339:
335:
325:
323:
314:
313:
306:
301:
281:
175:
146:Development of
133:Alma mater
128:(aged 103)
125:
116:
106:
100:
98:
97:
96:
86:
75:
64:
58:
55:
45:Please help to
44:
28:
24:
17:
12:
11:
5:
541:
531:
530:
525:
520:
515:
510:
505:
500:
495:
490:
485:
471:
470:
463:
462:External links
460:
457:
456:
437:(4): 734–740.
419:
391:
360:
333:
303:
302:
300:
297:
296:
295:
288:
280:
277:
247:978-0471035589
184:
183:
180:
179:
172:
168:
167:
162:
158:
157:
151:
150:
144:
143:Known for
140:
139:
134:
130:
129:
122:
118:
117:
107:
94:
92:
88:
87:
84:
77:
76:
31:
29:
22:
15:
9:
6:
4:
3:
2:
540:
529:
526:
524:
521:
519:
516:
514:
511:
509:
506:
504:
501:
499:
496:
494:
491:
489:
486:
484:
481:
480:
478:
469:
466:
465:
452:
448:
444:
440:
436:
432:
431:
423:
415:
411:
407:
404:
403:
395:
387:
383:
379:
375:
374:J. Chem. Educ
371:
364:
356:
352:
348:
344:
337:
321:
317:
311:
309:
304:
293:
289:
286:
283:
282:
276:
274:
270:
266:
261:
259:
255:
250:
248:
244:
240:
239:9780471283478
236:
232:
228:
224:
220:
216:
211:
209:
205:
200:
198:
194:
190:
181:
178:
173:
169:
166:
163:
159:
156:
152:
149:
145:
141:
138:
135:
131:
123:
119:
114:
110:
93:
89:
85:Ralph Pearson
82:
73:
70:
62:
59:February 2013
52:
48:
42:
41:
35:
30:
21:
20:
434:
428:
422:
405:
400:
394:
377:
373:
369:
363:
346:
342:
336:
324:. Retrieved
262:
251:
230:
212:
201:
188:
187:
171:Institutions
154:
126:(2022-10-12)
65:
56:
37:
488:2022 deaths
483:1919 births
349:(1): 3–15.
326:October 17,
265:Robert Parr
258:polarizable
215:Fred Basolo
51:introducing
477:Categories
299:References
290:Member of
101:1919-01-12
34:references
451:55897650
199:(HSAB).
113:Illinois
279:Honours
109:Chicago
47:improve
449:
245:
237:
161:Fields
115:, U.S.
36:, but
447:S2CID
328:2022
294:1974
243:ISBN
235:ISBN
221:and
121:Died
91:Born
439:doi
410:doi
382:doi
372:".
351:doi
347:187
249:).
479::
445:.
435:27
433:.
406:85
378:45
376:.
345:.
318:.
307:^
111:,
453:.
441::
416:.
412::
388:.
384::
357:.
353::
330:.
233:(
103:)
99:(
72:)
66:(
61:)
57:(
43:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.