National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
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XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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III.D.11.

Calculated Proton Affinity

Name	Species		Species	Name
1,2,4,5-Hexatetraene	C6H6	→	C6H7+	benzene, protonated

Bonding changes
Bond type C-C changed by +3 Bond type C=C changed by -2 Bond type H-C changed by +1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	1003
	G3	1002
	G3B3	1003
	G4	1006
	CBS-Q	1001

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Proton Affinities in kJ/mol

Methods with standard basis sets

		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ
hartree fock	HF	1397	1080	1080	1099	1110	1114	1096	1091	1092	1107	1088	1100	1089	1097	1087
density functional	LSDA	1336	1082	1082	1085	1089	1092	1068	1059	1059	1085	1056	1078	1058	1069	1056
	BLYP	1298	1057	1057	1059	1064	1068	1039	1032	1034	1058	1027	1051	1028	1038	1025
	B1B95	1320	1078	1078	1082	1087	1087	1071	1065	1066	1083	1062	1077	1064	1071
	B3LYP	1321	1070	1070	1076	1082	1085	1061	1053	1054	1076	1048	1070	1050	1059	1048
	B3LYPultrafine		1070			1082	1085	1061	1053			1048	1070	1050	1059	1048
	B3PW91	1330	1084	1084	1089	1094	1097	1079	1071	1072	1090	1069	1085	1069	1079	1068
	mPW1PW91	1339	1090	1090	1096	1101	1104	1085	1078	1079	1097	1075	1091	1077	1086	1075
	M06-2X	1325	1061	1061	1067	1067	1071	1051	1045	1046	1059	1042	1057	1040	1052	1039
	PBEPBE	1317	1077	1077	1077	1081	1085	1061	1056		1078	1051	1070	1053	1061	1050
	PBEPBEultrafine		1077			1081	1085	1061	1056			1051	1070	1053	1061	1050
	PBE1PBE	1344	1091	1091	1095	1101	1101	1084	1078	1079	1097	1075	1091	1076	1085	1074
	HSEh1PBE	1342	1088	1088	1093	1098	1102	1082	1075	1076	1094	1072	1088	1073	1082	1071
	TPSSh	1324	1083	1083	1087	1094	1098	1078	1072	1073	1090	1068	1085	1069	1079	1067
	wB97X-D	1348	1092	1092	1101	1105	1108	1089	1080	1080	1100	1078	1089	1079	1089	1077
	B97D3	1322	1087	1087	1090	1095	1098	1076	1071	1072	1090	1065	1084	1067	1076	1064
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ
Moller Plesset perturbation	MP2	1340	1052	1052	1059	1089	1103	1078	1065	1074	1087		1083	1068	1069	1062
	MP2=FULL	1340	1052	1052	1059	1088	1103	1078	1065	1075	1094		1083	1070	1070	1066
	MP3					1085		1078					1079
	MP3=FULL		1046	1046	1055	1085	1100	1078	1063	1073	1089		1079		1067
	MP4		1042			1080				1068			1077	1063	1064
	MP4=FULL		1042			1079							1077
	B2PLYP	1334	1066	1066	1073	1087	1094	1070	1061	1064	1082	1061	1077	1059	1066	1055
	B2PLYP=FULL	1334	1066	1066	1073	1087	1094	1070	1061	1064	1084	1061	1077	1059	1066
Configuration interaction	CID		1061	1061	1074	1102			1082
	CISD		1061	1061	1074	1102			1082					1089
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ
Quadratic configuration interaction	QCISD		1027	1027	1036	1073	1087	1067	1053		1075		1070		1061
	QCISD(T)					1073			1052				1070		1059
	QCISD(T)=FULL					1072		1065					1070
Coupled Cluster	CCD				1034	1073	1088	1067	1053	1062	1075		1069		1059
	CCSD					1073							1070		1061
	CCSD=FULL					1073					1082		1070		1061
	CCSD(T)					1073	1087	1065	1052	1062			1070
	CCSD(T)=FULL					1072							1070
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ

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Proton Affinities in kJ/mol

Methods with effective core potentials (select basis sets)

		CEP-31G	CEP-31G*	CEP-121G	CEP-121G*	LANL2DZ	SDD	cc-pVTZ-PP	aug-cc-pVTZ-PP	Def2TZVPP
hartree fock	HF	1135	1146	1099	1100	1093	1093
density functional	B3LYP	1103	1111	1071	1071	1071	1071
	wB97X-D	1132	1141	1099	1098	1099	1099
Moller Plesset perturbation	MP2	1079	1114			1038	1037

For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.