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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XVI	Bibliographic 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
diazirine	CH2N2	→	NCNH3+	Cyanamide, protonated

Bonding changes
Bond type C-N changed by -1 Bond type H-C lost 2 Bond type N=N lost 1 Bond type C#N gained 1 Bond type H-N gained 3

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	822
	G3	831
	G3B3	835
	G4	828
	CBS-Q	824

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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	1023	1062	1062	1015	876	897	893	889	902	896		905	893	897	886	895	895
density functional	LSDA					818
	BLYP	930	979	979	938	847	862	850	861	870	868			860	866
	B1B95	935	982	982	939	827	820	836	840	850	848			840	846	833	853
	B3LYP	948	999	999	955	851	868	858	866	876	872		874	865	872	856	868
	B3LYPultrafine					851											868
	B3PW91	943	995	995	953	844	861	854	857	868	865			856	865
	mPW1PW91	946	998	998	955	842	860	853	856	867	863			855	864
	M06-2X			1000		835
	PBEPBE	924	970	970	930	831	847	837	844	854	851			843	851
	PBEPBEultrafine					831
	PBE1PBE					837
	TPSSh					831		840							851
	wB97X-D			1006		848		858		871			873	868	869		867
	B97D3											868
		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	1049	1025	1025	987	863	885	874	868	884	878		885	880	874		868
	MP2=FULL	1050	1025	1025	987	865	887	876	869	885	884			881	877		872
	MP3					858
	MP3=FULL					860		873
	MP4		1019			861				881
	B2PLYP					857									874		870
Configuration interaction	CID		1042	1042	996	865			873
	CISD		1041	1041	996	866			873
		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		1035	1035	993	867	888	878	871					882
	QCISD(T)					860
Coupled Cluster	CCD		1037	1037	993	865	886	877	871					880
	CCSD(T)					908								876	871	861	865
	CCSD(T)=FULL																869
		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	984	863	990	878	1005	1004			897
density functional	B3LYP	922	839	927	850	943	943			870
	PBEPBE									848
Moller Plesset perturbation	MP2	947	845	949	852	973	972			874

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.