399:
The NOTCH method includes many new, physically-motivated terms compared to the NDDO family of methods, is much less empirical than the other semi-empirical methods (almost all of its parameters are determined non-empirically), provides robust accuracy for bonds between uncommon element combinations,
211:
Within the framework of
Hartree–Fock calculations, some pieces of information (such as two-electron integrals) are sometimes approximated or completely omitted. In order to correct for this loss, semi-empirical methods are parametrized, that is their results are fitted by a set of parameters,
390:, are sometimes classified as semiempirical methods as well. More recent examples include the semiempirical quantum mechanical methods GFNn-xTB (n=0,1,2), which are particularly suited for the geometry, vibrational frequencies, and non-covalent interactions of large molecules.
896:
Michael J. S. Dewar; Eve G. Zoebisch; Eamonn F. Healy; James J. P. Stewart (1985). "Development and use of quantum molecular models. 75. Comparative tests of theoretical procedures for studying chemical reactions".
353:. Here the objective is to use parameters to fit experimental heats of formation, dipole moments, ionization potentials, and geometries. This is by far the largest group of semiempirical methods.
412:
304:. The implementations aimed to fit, not experiment, but ab initio minimum basis set results. These methods are now rarely used but the methodology is often the basis of later methods.
176:
370:. The OMx (x=1,2,3) methods can also be viewed as belonging to this class, although they are also suitable for ground-state applications; in particular, the combination of OM2 and
1246:"GFN2-xTB—An Accurate and Broadly Parametrized Self-Consistent Tight-Binding Quantum Chemical Method with Multipole Electrostatics and Density-Dependent Dispersion Contributions"
274:(PPP), can provide good estimates of the π-electronic excited states, when parameterized well. For many years, the PPP method outperformed ab initio excited state calculations.
204:
for treating large molecules where the full
Hartree–Fock method without the approximations is too expensive. The use of empirical parameters appears to allow some inclusion of
257:
approximation. Their results, however, can be very wrong if the molecule being computed is not similar enough to the molecules in the database used to parametrize the method.
1364:
739:
Pariser, Rudolph; Parr, Robert G. (1953). "A Semi-Empirical Theory of the
Electronic Spectra and Electronic Structure of Complex Unsaturated Molecules. II".
696:
Pariser, Rudolph; Parr, Robert G. (1953). "A Semi-Empirical Theory of the
Electronic Spectra and Electronic Structure of Complex Unsaturated Molecules. I.".
76:
1072:
Nanda, D. N.; Jug, Karl (1980). "SINDO1. A semiempirical SCF MO method for molecular binding energy and geometry I. Approximations and parametrization".
169:
64:
371:
98:
152:
110:
106:
162:
1010:"Optimization of parameters for semiempirical methods VI: More modifications to the NDDO approximations and re-optimization of parameters"
270:
These methods exist for the calculation of electronically excited states of polyenes, both cyclic and linear. These methods, such as the
213:
80:
271:
1115:
Dral, Pavlo O.; Wu, Xin; Spörkel, Lasse; Koslowski, Axel; Weber, Wolfgang; Steiger, Rainer; Scholten, Mirjam; Thiel, Walter (2016).
869:
Michael J. S. Dewar & Walter Thiel (1977). "Ground states of molecules. 38. The MNDO method. Approximations and parameters".
227:
114:
961:"Optimization of parameters for semiempirical methods V: Modification of NDDO approximations and application to 70 elements"
1058:
856:
322:
526:
Hückel, Erich (1932). "Quantentheoretische Beiträge zum
Problem der aromatischen und ungesättigten Verbindungen. III".
144:
34:
200:
formalism, but make many approximations and obtain some parameters from empirical data. They are very important in
140:
128:
42:
1166:"Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Benchmarks of Electronically Excited States"
254:
239:
212:
normally in such a way as to produce results that best agree with experimental data, but sometimes to agree with
121:
91:
68:
136:
49:
38:
56:
362:
Methods whose primary aim is to calculate excited states and hence predict electronic spectra. These include
1303:"Development of NOTCH, an all-electron, beyond-NDDO semiempirical method: Application to diatomic molecules"
1117:"Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Theory, Implementation, and Parameters"
201:
102:
226:
Semi-empirical methods follow what are often called empirical methods where the two-electron part of the
1314:
748:
705:
662:
586:
535:
492:
441:
205:
19:
640:
330:
84:
27:
1340:
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1097:
941:
628:
610:
559:
465:
1332:
1275:
1267:
1187:
1146:
1089:
1039:
990:
924:
James J. P. Stewart (1989). "Optimization of parameters for semiempirical methods I. Method".
799:
764:
721:
678:
602:
551:
508:
457:
191:
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614:
563:
469:
383:
132:
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1101:
945:
1207:"Density-functional tight binding—an approximate density-functional theory method"
1025:
976:
301:
1271:
1262:
1245:
1182:
1165:
1132:
1093:
803:
768:
725:
682:
606:
555:
512:
461:
1009:
960:
653:
Hoffmann, Roald (1963-09-15). "An
Extended HĂĽckel Theory. I. Hydrocarbons".
483:
Hückel, Erich (1931). "Quanstentheoretische Beiträge zum
Benzolproblem II".
1336:
1279:
1191:
1150:
1116:
1062:, Volume 2, Eds. K. B. Lipkowitz and D. B. Boyd, VCH, New York, 313, (1991)
1043:
994:
937:
859:, Volume 1, Eds. K. B. Lipkowitz and D. B. Boyd, VCH, New York, 45, (1990)
432:
Hückel, Erich (1931). "Quantentheoretische Beiträge zum
Benzolproblem I".
795:
782:
Pople, J. A. (1953). "Electron interaction in unsaturated hydrocarbons".
910:
882:
643:, Molecular Orbital Theory for Organic Chemists, Wiley, New York, (1961)
1085:
598:
577:
HĂĽckel, Erich (1933). "Die freien
Radikale der organischen Chemie IV".
547:
504:
453:
1327:
1302:
1244:
Bannwarth, Christoph; Ehlert, Sebastian; Grimme, Stefan (2019-03-12).
1222:
760:
717:
674:
289:
1206:
367:
363:
334:
318:
314:
230:
is not explicitly included. For π-electron systems, this was the
387:
350:
338:
326:
297:
293:
1164:
Tuna, Deniz; Lu, You; Koslowski, Axel; Thiel, Walter (2016).
585:(9–10). Springer Science and Business Media LLC: 632–668.
534:(9–10). Springer Science and Business Media LLC: 628–648.
413:
List of quantum chemistry and solid-state physics software
374:
is an important tool for excited state molecular dynamics.
491:(5–6). Springer Science and Business Media LLC: 310–337.
440:(3–4). Springer Science and Business Media LLC: 204–286.
249:
Semi-empirical calculations are much faster than their
1080:(2). Springer Science and Business Media LLC: 95–106.
631:, B. O'Leary and R. B. Mallion, Academic Press, 1978.
282:These methods can be grouped into several groups:
833:, Prentice Hall, 4th edition, (1991), pg 579–580
400:and is applicable to ground and excited states.
329:computer programs originally from the group of
170:
8:
278:Methods restricted to all valence electrons.
1205:Seifert, Gotthard; Joswig, Jan-Ole (2012).
253:counterparts, mostly due to the use of the
77:Multi-configurational self-consistent field
1250:Journal of Chemical Theory and Computation
1170:Journal of Chemical Theory and Computation
1121:Journal of Chemical Theory and Computation
790:. Royal Society of Chemistry (RSC): 1375.
386:, e.g. a large family of methods known as
177:
163:
15:
1326:
1261:
1181:
1140:
1033:
984:
899:Journal of the American Chemical Society
871:Journal of the American Chemical Society
238:. For all valence electron systems, the
99:Time-dependent density functional theory
61:Semi-empirical quantum chemistry methods
1365:Semiempirical quantum chemistry methods
846:, Wiley, Chichester, (2002), pg 126–131
424:
120:
90:
48:
26:
18:
926:The Journal of Computational Chemistry
111:Linearized augmented-plane-wave method
107:Orbital-free density functional theory
1211:WIREs Computational Molecular Science
844:Essentials of Computational Chemistry
7:
818:Approximate Molecular Orbital Theory
627:HĂĽckel Theory for Organic Chemists,
1301:Wang, Zikuan; Neese, Frank (2023).
784:Transactions of the Faraday Society
81:Quantum chemistry composite methods
1059:Reviews in Computational Chemistry
857:Reviews in Computational Chemistry
65:Møller–Plesset perturbation theory
14:
266:Methods restricted to π-electrons
661:(6). AIP Publishing: 1397–1412.
1307:The Journal of Chemical Physics
741:The Journal of Chemical Physics
698:The Journal of Chemical Physics
655:The Journal of Chemical Physics
115:Projector augmented wave method
747:(5). AIP Publishing: 767–776.
704:(3). AIP Publishing: 466–471.
1:
1014:Journal of Molecular Modeling
1008:Stewart, James J. P. (2013).
965:Journal of Molecular Modeling
959:Stewart, James J. P. (2007).
261:Preferred application domains
153:Korringa–Kohn–Rostoker method
222:Type of simplifications used
816:J. Pople and D. Beveridge,
145:Empty lattice approximation
1381:
208:effects into the methods.
129:Nearly free electron model
43:Modern valence bond theory
1026:10.1007/s00894-012-1667-x
977:10.1007/s00894-007-0233-4
272:Pariser–Parr–Pople method
255:zero differential overlap
122:Electronic band structure
92:Density functional theory
69:Configuration interaction
1263:10.1021/acs.jctc.8b01176
1183:10.1021/acs.jctc.6b00403
1133:10.1021/acs.jctc.5b01046
313:Methods that are in the
300:that were introduced by
137:Muffin-tin approximation
50:Molecular orbital theory
39:Generalized valence bond
1074:Theoretica Chimica Acta
202:computational chemistry
141:k·p perturbation theory
579:Zeitschrift fĂĽr Physik
528:Zeitschrift fĂĽr Physik
485:Zeitschrift fĂĽr Physik
434:Zeitschrift fĂĽr Physik
240:extended HĂĽckel method
35:Coulson–Fischer theory
938:10.1002/jcc.540100208
384:Tight-binding methods
820:, McGraw–Hill, 1970.
796:10.1039/tf9534901375
206:electron correlation
20:Electronic structure
1319:2023JChPh.158r4102W
911:10.1021/ja00299a024
883:10.1021/ja00457a004
753:1953JChPh..21..767P
710:1953JChPh..21..466P
667:1963JChPh..39.1397H
641:Andrew Streitwieser
591:1933ZPhy...83..632H
540:1932ZPhy...76..628H
497:1931ZPhy...72..310H
446:1931ZPhy...70..204H
85:Quantum Monte Carlo
57:Hartree–Fock method
28:Valence bond theory
1086:10.1007/bf00574898
855:J. J. P. Stewart,
599:10.1007/bf01330865
548:10.1007/bf01341936
505:10.1007/bf01341953
454:10.1007/bf01339530
103:Thomas–Fermi model
1328:10.1063/5.0141686
1223:10.1002/wcms.1094
971:(12): 1173–1213.
905:(13): 3902–3909.
877:(15): 4899–4907.
831:Quantum Chemistry
761:10.1063/1.1699030
718:10.1063/1.1698929
675:10.1063/1.1734456
196:are based on the
192:quantum chemistry
187:
186:
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1265:
1256:(3): 1652–1671.
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1234:
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1176:(9): 4400–4422.
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1127:(3): 1082–1096.
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288:Methods such as
242:was proposed by
179:
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149:GW approximation
16:
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349:, PM6, PM7 and
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190:Semi-empirical
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73:Coupled cluster
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12:
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5:
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1313:(18): 184102.
1293:
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1217:(3): 456–465.
1197:
1156:
1107:
1064:
1049:
1000:
951:
932:(2): 209–220.
916:
888:
861:
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842:C. J. Cramer,
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244:Roald Hoffmann
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629:C. A. Coulson
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581:(in German).
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331:Michael Dewar
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232:HĂĽckel method
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133:Tight binding
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829:Ira Levine,
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333:. These are
281:
269:
250:
248:
236:Erich HĂĽckel
234:proposed by
225:
214:
210:
198:Hartree–Fock
189:
188:
60:
1056:M. Zerner,
1020:(1): 1–32.
228:Hamiltonian
419:References
302:John Pople
1345:258565304
1272:1549-9618
1231:121521740
1094:0040-5744
804:0014-7672
769:0021-9606
726:0021-9606
683:0021-9606
615:121710615
607:1434-6001
564:121787219
556:1434-6001
513:1434-6001
470:186218131
462:1434-6001
251:ab initio
218:results.
215:ab initio
1359:Category
1337:37154284
1288:73419235
1280:30741547
1192:27380455
1151:26771204
1102:98468383
1044:23187683
995:17828561
946:36907984
407:See also
1315:Bibcode
1142:4785507
1035:3536963
986:2039871
749:Bibcode
706:Bibcode
663:Bibcode
587:Bibcode
536:Bibcode
493:Bibcode
442:Bibcode
325:and/or
323:SPARTAN
194:methods
22:methods
1343:
1335:
1286:
1278:
1270:
1229:
1190:
1149:
1139:
1100:
1092:
1042:
1032:
993:
983:
944:
802:
767:
724:
681:
613:
605:
562:
554:
511:
468:
460:
290:CNDO/2
1341:S2CID
1284:S2CID
1227:S2CID
1098:S2CID
942:S2CID
611:S2CID
560:S2CID
466:S2CID
368:SINDO
364:ZINDO
335:MINDO
319:AMPAC
315:MOPAC
1333:PMID
1276:PMID
1268:ISSN
1188:PMID
1147:PMID
1090:ISSN
1040:PMID
991:PMID
800:ISSN
765:ISSN
722:ISSN
679:ISSN
603:ISSN
552:ISSN
509:ISSN
458:ISSN
388:DFTB
372:MRCI
366:and
351:SAM1
339:MNDO
327:CP2K
298:NDDO
296:and
294:INDO
1323:doi
1311:158
1258:doi
1219:doi
1178:doi
1137:PMC
1129:doi
1082:doi
1030:PMC
1022:doi
981:PMC
973:doi
934:doi
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