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
thiomethoxy	CH3S	→	CH3SH+	Methanethiol cation

Bonding changes
Bond type H-S gained 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G4	736

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Proton Affinities in kJ/mol

Methods with standard basis sets

		3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	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	671	729		739	750	750	742	761		757	753		754		762
density functional	LSDA				737			731
	BLYP	715	756		759	768	759
	B3LYP	704	749	711	754	762		748	770		758	763		755
	B3LYPultrafine												764		763
	B3PW91	702	748	712	755	764		753	774			766
	mPW1PW91	702			756	764	760	754					768
	M06-2X				739
	PBEPBEultrafine				756
	PBE1PBE				748
	HSEh1PBE				747		753						764
	TPSSh				758		763		776				774
	wB97X-D														761
	B97D3									785
		3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	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	688	734		739	762	760	737	752		763	758	755	748
	MP2=FULL	688			739	763	761					759
	MP3=FULL				746		768
	MP4				749
	B2PLYP				745								760
Configuration interaction	CID				747			746
	CISD				747
		3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	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				750	772	770	750				770
Coupled Cluster	CCD				748			748
	CCSD				750
		3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	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	685	744		747		681			766
density functional	B3LYP									768
	PBEPBE									772
Moller Plesset perturbation	MP2					697				759

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.