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.F.2.

Completed calculations for C₂H⁺ (Ethynyl cation)

Methods and basis sets for which an energy has been calculated. "e" indicates just an energy has been calculated. "o" indicates an optimized geometry. "v" indicates vibrational frequencies. "s" followed by a number indicates completed calculations for different states (for example s1ov). "c" followed by a number indicates completed calculations for different conformations (for example c2ov).
See the Calculated Energies page (section III.A.1) for more calculated properties.

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Methods with predefined basis sets

semi-empirical	PM3	s1c1ov s2c1ov s1c2o
composite	G1	s1c1e s2c1e
	G2MP2	s1c1e s2c1e
	G2	s1c1e s2c1e
	G3	s1c1e s2c1e
	G3B3	s1c1e
	G3MP2	s1c1e
	G4	s1c1e s2c1e
	CBS-Q	s1c1e s2c1e

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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	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov s1c2ov
density functional	LSDA	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov
	BLYP	s1c1o s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1o s2c1ov	s1c1o s2c1o s1c2ov	s1c1o s2c1ov	s1c1o s2c1ov	s1c1o s2c1ov	s1c1o s2c1ov	s1c1o s2c1ov			s1c1o s2c1ov	s1c1o s2c1ov
	B1B95	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov
	B3LYP	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov
	B3LYPultrafine		s2c1ov	s2c1ov	s2c1ov	s1c1ov s2c1ov	s2c1ov	s2c1ov	s2c1ov	s2c1ov	s2c1ov			s2c1ov	s2c1ov			s1c1ov s2c1ov
	B3PW91	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov
	mPW1PW91	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov
	M06-2X			s1c1ov s2c1ov s1c2ov		s1c1ov						s1c1ov s2c1ov s1c2ov
	PBEPBE	s1c1o s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov
	PBE1PBE					s1c1ov s2c1ov
	HSEh1PBE		s1c1ov			s1c1ov		s1c1ov							s1c1ov
	TPSSh					s1c1ov s2c1ov		s1c1ov s2c1ov			s1c1ov s2c1ov				s1c1ov s2c1ov
	wB97X-D			s1c1ov s2c1ov s1c2ov		s1c1ov s2c1ov s1c2ov		s1c1ov s2c1ov s1c2ov		s1c1ov s2c1ov s1c2ov			s1c1ov s2c1ov s1c2ov	s1c1ov s2c1ov s1c2ov	s1c1ov s2c1ov s1c2ov			s1c1ov s2c1ov s1c2ov
	B97D3		s1c1ov s2c1o s1c2o			s1c1o s2c1o s1c2o		s1c1o s2c1o s1c2o		s1c1o s2c1o s1c2o		s1c1o s2c1o s1c2o	s1c1ov s2c1o s1c2o		s2c1o s1c2ov			s1c1o s2c1o s1c2o		s1c1o s2c1o s1c2ov
		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	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1o	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov
	MP2=FULL	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1o		s1c1ov s2c1ov	s1c1ov
	MP3					s1c1ov		s1c1o s2c1o
	MP3=FULL					s1c1ov s2c1ov		s1c1ov s2c1ov
	MP4		s1c1ov s2c1ov			s1c1ov s2c1ov				s1c1ov s2c1ov					s1c1ov
	B2PLYP					s1c1ov									s1c1ov s2c1ov
	B2PLYP=FULLultrafine					s1c1ov s2c1ov s1c2ov								s1c1ov s2c1ov s1c2ov	s1c1ov s2c1ov s1c2ov			s1c1ov s2c1ov s1c2ov
Configuration interaction	CID		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov
	CISD		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov
		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		s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov
	QCISD(T)					s1c1ov s2c1ov								s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1o s1c2o	s1c1o s2c1ov
Coupled Cluster	CCD		s2c1o	s1c1ov s2c1o	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1ov s2c1ov	s1c1ov s2c1ov
	CCSD					s2c1ov
	CCSD(T)					s1c1ov s2c1ov								s1c1ov s2c1ov	s1c1ov s2c1ov		s1c1ov s2c1ov	s1c1ov s2c1ov
	CCSD(T)=FULL					s1c1ov s2c1ov
		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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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	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov s1c2ov
density functional	B3LYP	s1c1ov s2c1ov	s1c1ov s2c1o	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov s1c2ov
	PBEPBE									s1c1ov s2c1ov s1c2ov
Moller Plesset perturbation	MP2	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov	s1c1ov s2c1ov			s1c1ov s2c1ov s1c2ov

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Single point energy calculations (select basis sets)

		cc-pVTZ	aug-cc-pVTZ
Moller Plesset perturbation	MP2FC// B3LYP/6-31G*	s1c1e s2c1e
	MP2FC// MP2FC/6-31G*		s2c1e
Coupled Cluster	CCSD(T)// B3LYP/6-31G*	s1c1e s2c1e
	CCSD// MP2FC/6-31G*		s2c1e
	CCSD(T)// MP2FC/6-31G*		s2c1e

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.