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
Carbonic acid	H2CO3	→	H3CO3+	carbonic acid, protonated

Bonding changes
Bond type C-O changed by +1 Bond type H-O changed by +1 Bond type C=O lost 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	730
	G3	731
	G3B3	732
	G4	733
	CBS-Q	726

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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	1017	795	795	764	776	796	781	772	790	804		781	793	794	782	790	790
density functional	LSDA	1004	785	785	748	762	777	747	744	761	783			775	760	748	752
	BLYP	1004	792	792	757	774	789	754	758	773	795			786	770
	B1B95	997	789	789	758	773	773	766	763	779	797			787	780	767	773
	B3LYP	1003	792	792	758	774	790	761	760	777	797		761	787	776	762	767
	B3LYPultrafine					774											767
	B3PW91	1002	792	792	760	776	793	769	765	782	800			790	783
	mPW1PW91	1002	791	791	760	776	793	769	765	782	800			790	784	770	777
	M06-2X	1001	780	780	752	766	782	760	753	769	789			779	767	761	761
	PBEPBE	1005	789	789	756	773	789	759	759	776	796			786	775	760	765
	PBE1PBE					774
	HSEh1PBE	1003	790	790	758	774	790		762	780	798			788	781	768	773
	TPSSh					777		768			799				782
	wB97X-D			796		778		771		784			774	771	787		781
	B97D3		797			785		773		789		778	775		789		780
		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	1021	779	779	734	751	777	750	747	774	777		756	780	766	747	753
	MP2=FULL	1021	779	779	735	752	778	751	747	775	778			781	769	748	756
	MP3					765
	MP3=FULL					765		770
	MP4		783			757				780					771
Configuration interaction	CID		794	794	755	768			765
	CISD		794	794	755	768			765
		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		792	792	750	764	790	765	759	787	790			792	780	762	769
	QCISD(T)					761								791	776
Coupled Cluster	CCD		791	791	749	764	790	767	760	788	790			793	781	764	770
	CCSD					764								793	781
	CCSD(T)					761								791	776	758	763
	CCSD(T)=FULL					762								791	780	759
		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	761	767	761	767	766	766			792
density functional	B3LYP	746	758	746	758	753	753			771
	PBEPBE									770
Moller Plesset perturbation	MP2	722	735	720	733	727	726			761

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.