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 C₆H₂ (hexatriyne)

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	ov
composite	G1	e
	G2MP2	e
	G2	e
	G3	e
	G3B3	e
	G4	e
	CBS-Q	e

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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	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
hartree fock	HF	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
density functional	LSDA	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	BLYP	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov
	B1B95	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	B3LYP	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	B3LYPultrafine		ov			ov	ov	ov	ov				ov	ov	ov	o	ov
	B3PW91	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov
	mPW1PW91	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	M06-2X	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	o	ov
	PBEPBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	PBEPBEultrafine		ov			ov	ov	ov	ov				ov	ov	ov	o	ov
	PBE1PBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	HSEh1PBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	o	ov
	TPSSh		ov	ov	ov	ov	ov	ov	ov		ov		ov	ov	ov	o	ov
	wB97X-D			ov		ov		ov		ov			ov	ov	ov		ov
	B97D3		ov			ov		ov		ov		ov	ov		ov		ov	dnf
		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	ov	o	o	o	o	o	o	o	o	o		ov	ov	ov	o	ov
	MP2=FULL	ov	o	o	o	o	o	o	o	o	ov		ov	ov	o	o	ov
	MP3					o		o					ov	ov	ov
	MP3=FULL					o		o					ov	ov	ov
	MP4		o			o				o			o	ov	ov	o	o
	MP4=FULL		o			o				o				ov	ov	o	o
	B2PLYP	ov	o	o	o	ov	ov	o	o	o	ov		ov	ov	ov	o	o
	B2PLYP=FULL	ov	o	o	o	ov	ov	o	o	ov	ov		ov	ov	ov	o	o
	B2PLYP=FULLultrafine					ov								ov	ov		ov
Configuration interaction	CID		o	o	o	ov			o
	CISD		o	o	o	ov			o
		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	ov	o	o	o	o	o	dnf	o	dnf	dnf		ov	ov	dnf	o	ov
	QCISD(T)					o							o	ov	ov	o	o
	QCISD(T)=FULL					o		o						ov	ov	o	o
Coupled Cluster	CCD	ov	o	o	o	o	o	dnf	o	dnf	dnf		ov	ov	dnf	o	o
	CCSD					o				dnf			ov	ov	ov	o	dnf
	CCSD=FULL					o							ov	ov	ov	o	dnf
	CCSD(T)					o				o			o	ov	ov	o	o
	CCSD(T)=FULL					o							ov	ov	ov	o	o
		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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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	ov	ov	ov	ov	ov	ov			ov
density functional	B3LYP	ov	o	ov	ov	ov	ov			ov
	PBEPBE									ov
Moller Plesset perturbation	MP2	o	ov	o	ov	ov	ov			ov

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.