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
cyanamide	NH2CN	→	NCNH3+	Cyanamide, protonated

Bonding changes
Bond type H-N changed by +1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G4	655

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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	887	707	707	685	687	695	685	686	690	695		689	693	688	683	685	685
density functional	LSDA		706	706	680	676	680	660	663					676	661	655	656
	BLYP	881	733	733	707	701	707	684	691	693	704			701	687
	B1B95	872	720	720	699	694	668	676	663	682	691			688	687	680	683
	B3LYP	880	724	724	700	696	702	683	688	690	700		683	697	685	677	680
	B3LYPultrafine		724			696		683							685		680
	B3PW91	879	722	722	702	697	703	688	691	693	702			699	690
	mPW1PW91	879	720	720	700	696	702	687	690	692	701			698	690
	M06-2X		713	713	694	688
	PBEPBE	881	727	727	704	698	704	684	690	692	702			698	687
	PBEPBEultrafine		727			698
	PBE1PBE		719	719	698	693
	HSEh1PBE		718	718	697	693		684							686
	TPSSh		727	727	707	703		693							695
	wB97X-D			725		699		690		695			693	701	694		691
	B97D3											696
		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	951	749	749	720	702	717		698	707	702		702	712	693	687	685
	MP2=FULL	952	749	749	720	702	717	699	698	707	704			713	695		687
	MP3					703
	MP3=FULL					703		703
	MP4		755			708				714
	MP4=FULL		755
	B2PLYP		731	731	705	698									688		681
	B2PLYP=FULL		731	731	705
Configuration interaction	CID		744	744	715	701
	CISD		743	743	715	701
		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		756	756	725	708	723	706	705	714	708			719	701
	QCISD(T)					709
Coupled Cluster	CCD		756	756	726	708	723	707	705	714	708			719	701
	CCSD(T)					709
		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	684	685	687	686	683	683			686
density functional	B3LYP	691	689	693	689	694	694			682
	PBEPBE									683
Moller Plesset perturbation	MP2	714	697	713	696	713	713			690

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.