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
Hydrogen cyanide	HCN	→	CNH2+	N-protonated hydrogen isocyanide

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

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	469
	G3	467
	G3B3	468
	G4	471
	CBS-Q	467

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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	681	562	562	565	545	563	556	539	551	561		547	556	553	552	554	552	552	552
density functional	LSDA	572	472	472	468	467	480	468	452	462	482			472	463		466	461
	BLYP	605	500	500	499	496	510	495	483	493	512			500	491
	B1B95	602	506	506	505	500	500	505	492	502	516			506	503		503	501
	B3LYP	612	507	507	507	502	517	505	491	501	518		495	508	500	499	502	498	498
	B3LYPultrafine					502												498
	B3PW91	605	508	508	508	503	517	508	493	504	518			509	504
	mPW1PW91	607	510	510	510	504	519	510	495	506	519			510	506		507	505
	M06-2X			505
	PBEPBE	591	494	494	492	490	504	492	479	490	505			495	489		489	487
	PBE1PBE					500
	TPSSh					503		507			516				504
	wB97X-D			518		512		517		512			508	513	513			512
	B97D3		518			513		516		514		510	508		514			511
		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	541	456	456	446	452	477	467	444	465	465		460	470	461	456	461	456	454
	MP2=FULL	541	456	456	447	451	476	466	443	465	464			470	458	455	460	453	453
	MP3					500
	MP3=FULL					499		516
	MP4		495			481				494					486
	B2PLYP														487
Configuration interaction	CID		514	514	512	508			501
	CISD		516	516	514	507			500
		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		509	509	506	502	526	517	495	515	514			521	510		513	506
	QCISD(T)					494								514	501
Coupled Cluster	CCD		506	506	503	503	528	519	496	517	516			522	512		514	508
	CCSD					502								521	511
	CCSD(T)					494								514	501	497	505	497	495
	CCSD(T)=FULL					-2905								514	497	495	505	493
		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	569	553	567	542	565	565			552
density functional	B3LYP	524	518	522	510	506	507			499
	PBEPBE									488
Moller Plesset perturbation	MP2	460	460	449	451	443	442			458

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.