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
hydroxycarbene	HOCH	→	CH2OH+	hydroxymethyl cation

Bonding changes
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	885
	G3	886
	G3B3	888
	CBS-Q	885

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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	daug-cc-pVTZ
hartree fock	HF	1088	927	927	926	940	947	930	931	938	950		933	940	941	939	929	937	938	937
density functional	LSDA	1121	944	944	939	932	935	907	912	917	932		909	923	914		901	908
	BLYP	1098	947	947	943	942	946	915	923	929	943		918	932	926
	B1B95	1098	945	945	945	944	966	926	930	935	947		929	937	934		921	929
	B3LYP	1098	946	946	943	943	948	921	927	932	946		924	935	931	928	916	924	925
	B3LYPultrafine					943								935	931		916	924
	B3PW91	1104	948	948	948	947	952	930	933	939	951		933	942	939
	mPW1PW91	1104	947	947	947	947	952	930	934	940	952		933	942	939		926	934
	M06-2X	1095	935	935	934	931	936	914	917	922	935		916	925	920		910	915
	PBEPBE	1108	947	947	946	944	948	921	927	933	946		924	936	930		916	923
	PBEPBEultrafine					944								936	930		916	923
	PBE1PBE	1107	946	946	945	945	945	928	931	937	949		931	940	937		924	931
	HSEh1PBE	1106	946	946	945	945	950		931	937	949		930	939	936		923	930
	TPSSh					950		933			954				942
	wB97X-D			950		948		930		939			935	930	941			936
	B97D3		951			953		932		943		935	936		942			935
		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	daug-cc-pVTZ
Moller Plesset perturbation	MP2	1159	960	960	949	946	960	934	933	944	950		938	948	938	933	923	928	929
	MP2=FULL	1159	960	960	949	947	961	936	933	944	953		939	949	944	936	924	933	932
	MP3					940
	MP3=FULL					941		934
	MP4		957			941				940			935	944	933		917	923
	MP4=FULL		957			942				941				945	940		918	929
Configuration interaction	CID		951	951	941	941			930
	CISD		953	953	944	942			931
		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	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		955	955	944	939	955	931	927	939	945		935	942	933		918	925
	QCISD(T)					939							933	942	931		915	922
Coupled Cluster	CCD		951	951	940	937	952	929	924	937	943		933	940	932		917	924
	CCSD					938							934	942	933	929	918	925
	CCSD=FULL					940							935	943	940	933	919	931
	CCSD(T)					939							933	942	931	926	915	922	922
	CCSD(T)=FULL					940							934	943	938	930	917	928	926
		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	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	907	924	908	927	914	913			938
density functional	B3LYP	911	917	911	918	927	927			927
	PBEPBE									926
Moller Plesset perturbation	MP2	916	921	918	923	927	926			934

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.