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
diiminomethane	HNCNH	→	NH2CNH+	cyanamide, cn protonated

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

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	775
	G3	779
	G3B3	787
	G4	786
	CBS-Q	775

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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-pVDZ	daug-cc-pVTZ
hartree fock	HF	1042	906	906	885	840	851	839	840	846	851	837	846	842	842	840	827	837	838	827	837
density functional	BLYP		865	865
	B1B95		866	866	848
	B3LYP		875	875	857
	B3LYPultrafine		875
	B3PW91		875	875	859
	mPW1PW91		876	876	860
	M06-2X		876	876	861					816	826		814
	PBEPBE		861	861								798
	PBEPBEultrafine		861
	PBE1PBE		874	874	857
	HSEh1PBE		874	874	857
	TPSSh		868	868	855	820								821
	wB97X-D		886	886	868
	B97D3		871	871
		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-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2		891	891
	MP2=FULL		891	891							832	808			822
	MP3											820
	MP3=FULL		910	910	884	833				843	843	823			836
	MP4		888
	MP4=FULL		888
	B2PLYP		879	879	857
	B2PLYP=FULL		879	879	857
	B2PLYP=FULLultrafine		879	879	857
Configuration interaction	CID		911	911	886	836			835			828			837
	CISD		908	908	884	834			834			827			836
		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-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		907	907
Coupled Cluster	CCD		912	912						844	841	823			833
	CCSD										839
	CCSD=FULL										843	823			835
		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-pVDZ	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	886	832	884	833	885	885			840
density functional	B3LYP	850		848		851	851
	wB97X-D	869	822	866		868	868
Moller Plesset perturbation	MP2	857	808	853		855	855
	MP3=FULL									829
Configuration interaction	CID									834
	CISD									833
Coupled Cluster	CCD									830
	CCSD=FULL									829

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.