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
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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
Oxirene	C2H2O	→	CH2COH+	ketene, protonated

Bonding changes
Bond type C-O lost 2 Bond type H-O gained 1 Bond type C=O gained 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	923
	G3	928
	G3B3	923
	G4	920
	CBS-Q	922

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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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ
hartree fock	HF	1130	1047	1047	1022	1018	1036	1020	1020	1035	1043	1024	1023	1039	1031	1028	1022	1024	1026
density functional	BLYP	1096
	B1B95	1082	1009	1009	976	976	976	969	974	988	997	972	975		981		969	972
	B3LYP	1096						964						976
	B3PW91	1093	1016	1016								981					976	981
	mPW1PW91	1092	1016	1016	982		998	977			1004	981	983		989		976	981
	M06-2X	1077				964	978	958	960	973	984		961	977	966			959
	PBEPBE											963
	PBE1PBE	1093	1013	1013	979	979	979	973		991	1000	976	979		985		972	976
	HSEh1PBE	1093	1015	1015	980			974			1002	977	979		985		973	977
	TPSSh	1088				974						970		986				970	971
	wB97X-D	1093			987	988	1002	982		999	1009	986	988		995	992		987	989
	B97D3	1104
		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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ
Moller Plesset perturbation	MP2	1116	999	999	949			948			972	943			958	950		943	943
	MP2=FULL	1116	999	999	949		975	949			979	945			962	952		949	946
	MP3					966		972				970	980	1003	983
	MP3=FULL		1005	1005	964	968	994	973	972	998	1000	972	981	1004	987		972
	B2PLYP	1105
	B2PLYP=FULL	1105
	B2PLYP=FULLultrafine	1105
Configuration interaction	CID		1018	1018	979	981			985			986		1014	998
	CISD		1020	1020	981	982			986			986		1015	998
		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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ
Quadratic configuration interaction	QCISD		1009	1009	967	972	997	974	974	1000	997	971	982		985		971
	QCISD(T)											959						960
	QCISD(T)=FULL							965				961						966
Coupled Cluster	CCD		1006	1006	963	967	993	971	971	997	994	970	979	1003	983		970	971
	CCSD					971					996	971		1005	984		971	972
	CCSD=FULL					972					1003	973	982	1006	988		972	978
	CCSD(T)					962	988	964			986	959			974	966	960	960
	CCSD(T)=FULL					963						961			977	968	961	966
		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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ

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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	1001	996	1003	1001	1017	1017			1028
density functional	B1B95									978
	B3LYP	953		955
	B3PW91									986
	mPW1PW91									986
	M06-2X									965
	PBE1PBE									981
	HSEh1PBE									982
	wB97X-D	963	967	965	971	980	980			992
Moller Plesset perturbation	MP2	920	923	921	924	936	935			953
	MP2=FULL									954
	MP3									979
	MP3=FULL									980
Configuration interaction	CID									994
	CISD									994
Quadratic configuration interaction	QCISD									980
	QCISD(T)									969
	QCISD(T)=FULL									970
Coupled Cluster	CCD									979
	CCSD									980
	CCSD(T)									969
	CCSD(T)=FULL									970

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.