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
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
VII	Tutorials and Units
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
XIII	Vibrations
XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
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
Guanidine	CH5N3	→	CH6N3+	guanidinium

Bonding changes
Bond type C-N changed by +1 Bond type H-N changed by +1 Bond type C=N lost 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	952
	G3	956
	G3B3	958
	G4	956
	CBS-Q	953

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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)	6-311+G(3df,2p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
hartree fock	HF	1215	1075	1075	1054	1023	1037	1018	1021	1029	1038		1021	1030	1028	1012	1020	1020
density functional	LSDA		1054			997	1004	974	985	991	1006			1000	985	969	974
	BLYP	1178	1058	1058	1037		1014	981	995	1001	1016		987	1008	995
	B1B95	1192	1063	1063	1044	1010	1010	996	1004	1011	1022		1001		1008		999
	B3LYP	1190	1063	1063	1042	1010	1020	992	1002	1009	1022		997	1015	1005	987	994
	B3LYPultrafine					1010
	B3PW91	1194			1046	1014	1024	1000	1007	1014	1026		1005	1019	1011
	mPW1PW91	1195	1066	1066	1046	1014	1024	1000	1008	1015	1026		1006	1019	1012	996	1003
	M06-2X	1192	1051	1051	1033	996		984	989		1009		986			979	981
	PBEPBE	1186	1057	1057	1037	1004	1014	985	997	1003	1015		991	1008	998	980	986
	HSEh1PBE	1196	1064	1064	1043	1010	1021		1005	1011	1023		1002	1016	1008	992	999
	TPSSh					1014					1023
	wB97X-D			1076		1019		1004		1018			1010	1004	1016		1008
	B97D3		1068			1017		1000		1017		1001	1007		1013		1003
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	6-311+G(3df,2p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2		1054	1054	1024	993	1011	982	989	998	1005		986	1003	989	967
	MP2=FULL		1055	1055	1025	994	1013	983	990	1000	1009		987	1004	995	968	979
	MP3					1003
	MP4		1056			994				1000
Configuration interaction	CID		1070	1070	1043	1013			1010
	CISD		1070	1070	1043	1012			1010
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	6-311+G(3df,2p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		1063	1063	1035	1001	1020	993	997	1008	1015		997	1012	1002	980
	QCISD(T)					996							991	1007
Coupled Cluster	CCD		1062	1062	1035	1002	1021	995	998	1010	1016		999	1013	1004	982	992
	CCSD					1002								1012	1003
	CCSD(T)					996							991	1007
	CCSD(T)=FULL					997							992	1008
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	6-311+G(3df,2p)	TZVP	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ	daug-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	1046	1009	1043	1008	1048	1048			1024
density functional	B3LYP	1027	992	1025	991	1033	1033			1000
	PBEPBE									992
Moller Plesset perturbation	MP2	1009	973	1003	970	1012	1011			984

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.