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
silicon dihydride	SiH2	→	SiH3+	Silyl cation

Bonding changes
Bond type H-Si changed by +1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	883
	G3	871
	G3B3	873
	G4	877
	CBS-Q	878

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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	cc-pV(T+d)Z	daug-cc-pVTZ
hartree fock	HF	1140	806	847	812	854	860	859	852	861	862		859	852	860	862	853	860	862	862	860
	ROHF		806	847	812	854	860	867	852	861			859	852	860	862	853	860	862
density functional	LSDA	1159	636	851	841	858	860	858	857	860	862		859	855	860		854	861
	BLYP	1180	870	891	874	895	898	895	893	898	901		897	892	899
	B1B95	1163		884	865	889	893	891	887	893	895		892	888	895			894
	B3LYP	1177	867	892	872	897	901	899	896	901	904		900	894	902	904	893	902	905	904
	B3LYPultrafine					897		814					900	894	902		893	902
	B3PW91	1162	850	874	858	881	884	883	880	886	888		885	880	887
	mPW1PW91	1158	846	871	852	877	880	879	876	881	884		880	876	883		877	883
	M06-2X	1155	855	883	859	885	889	887	882	889	892		891	887	893		886	893
	PBEPBE	1161	845	864	850	869	872	870	868	873	875	806	872	868	873		867	873
	PBEPBEultrafine					869							872	868	873		866	873
	PBE1PBE	1158		867	848	873	873	874	871	877	879		876	871	878		871	878
	HSEh1PBE	1158	842	867	848	873	877		872	878	880		877	872	879		872	879
	TPSSh		855	883	861	887	891	889	886		895		892	888	894		889	894
	wB97X-D			895		906		908		910			910	908	912			912
	B97D3		880			905		905		907		910	907		909			909
		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	cc-pV(T+d)Z	daug-cc-pVTZ
Moller Plesset perturbation	MP2	1178	839	872	844	877	895	894	877	899	891		893	883	894	897	882	895	899
	MP2=FULL	1182	840	872	845	878	896	895	877	899	892		894	884	899	905	884	901	908	901
	ROMP2	1179		872	845	878	895	895	877	899	892		893	883	895		882
	MP3					882		901					899	889	899
	MP3=FULL					882		902					901	891	904
	MP4		849			882				908			900	890	899		888	899
	MP4=FULL		850			883				908				892	904		891	906
	B2PLYP					816
Configuration interaction	CID		846	876	851	881			880						823
	CISD		846	875	851	880			879						822
		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	cc-pV(T+d)Z	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		849	877	854	882	902	901	881	907	897		900	890	900		888	900
	QCISD(T)					881			881				900	890	898		887	897
Coupled Cluster	CCD		849	878	854	883	903	902	882	909	900		902	892	902		890	903
	CCSD					882							900	890	900	905	888	900	904
	CCSD=FULL					882							902	892	905	910	891	907	912
	CCSD(T)					881	901	900	881				900	890	898	902	887	897	901	900
	CCSD(T)=FULL					-7727							901	891	902	907	889	904	909
		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	cc-pV(T+d)Z	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	811	855	811	849	799	813			862
density functional	B3LYP	868	897	868	893	860	874			904
	PBEPBE									875
Moller Plesset perturbation	MP2	843	873	844	869	833	847			897

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.