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
Acetyl radical	CH3CO	→	C2H4O+	ethylene oxide cation

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

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	506
	G3	507
	G3B3	517
	G4	519
	CBS-Q	502

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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		625	625	599	598	604	592				590		590	571			594
	ROHF		625	625	599	596	601	570	585					588	593
density functional	BLYP	834				581				558
	B1B95	829	576	576	557	583	565	561	546	562	582			568	573	566
	B3LYP	838	582	582	565	575	580	556	551	556	579	551	551	565	557	553	553
	B3LYPultrafine					575		556							557		553
	B3PW91	838	584	584	569	583	587	569	563	569	588			575	572	567
	mPW1PW91	842	589	585	570	587	592	573	568	570	589			579	576	568
	M06-2X			572		568
	PBEPBE	836	586			588	593	568	565	570	594	565		579	572
	PBEPBEultrafine					588
	PBE1PBE					582
	HSEh1PBE		583			581		567							570
	TPSSh					602		588			607				591
	wB97X-D			579						563							564
	B97D3		593			593		576		577		573	571		580		575
		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					522			505
	MP3					566		591
	MP3=FULL					565		564
	B2PLYP					556		542							543
	B2PLYP=FULL		568			556		542
Configuration interaction	CID		592	592	566	569			555					567	568
	CISD		593	593	567	571			556					567	568
		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		582	582	555	565	579	561	549					562
	QCISD(T)					564								561
Coupled Cluster	CCD		586	586	559	562	578	560	547					560
	CCSD					567	582	564						564
		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	610	607	609	584					593
density functional	B3LYP	580	582	574	571	565	565			554
	PBEPBE									568
Moller Plesset perturbation	MP2									512

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.