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 C₆H₆ (2,4-Hexadiyne)

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	AM1	c1o
	PM3	c1ov c2o
composite	G1	c1e
	G2MP2	c1e
	G2	c1e
	G3	c1e
	G3B3	c1e
	G3MP2	c1e
	G4	c1e

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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	cc-pV(T+d)Z	daug-cc-pVTZ
hartree fock	HF	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov		c1o c2o	c1ov	c1ov	c1o	c1ov	c1ov
density functional	LSDA				c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov			c1ov	c1ov			c1ov
	BLYP	c1ov	c1ov		c1ov	c1ov	c1ov	c1ov		c1ov	c1ov			c1ov	c1ov			c1ov
	B1B95	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov			c1ov	c1ov			c1ov
	B3LYP	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov c2ov	c1ov	c1ov		c1ov	c1ov
	B3LYPultrafine														c1ov		c1o
	B3PW91	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov			c1ov	c1ov	c1ov		c1ov
	mPW1PW91	c1ov	c1ov		c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov			c1ov	c1ov			c1ov
	M06-2X			c1o c2o		c1o						c1ov
	PBEPBE	c1ov			c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov	c1ov		c1ov	c1ov			c1ov
	PBEPBEultrafine					c1o
	PBE1PBE					c1ov
	HSEh1PBE		c1ov			c1ov		c1ov							c1ov
	TPSSh					c1o		c1o			c1o				c1o
	wB97X-D			c1ov c2o		c1ov c2o		c1ov c2o		c1ov c2o			c1ov c2o	c1ov c2o	c1ov c2o		c1o c2o
	B97D3		c1o c2o			c1o c2o		c1o c2o		c1o c2o		c1o c2o	c1o c2o		c1o c2o		c1o c2o		c1dnf
		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	cc-pV(T+d)Z	daug-cc-pVTZ
Moller Plesset perturbation	MP2	c1ov				c1o			c1o				c1o c2o	c1ov	c1o
	MP2=FULL					c1ov
	MP3							c1o
	MP3=FULL					c1o		c1o
	B2PLYP					c1o									c1dnf
	B2PLYP=FULLultrafine					c1o								c1o	c1o		c1o
		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	cc-pV(T+d)Z	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		c1ov	c1ov	c1ov	c1ov	c1ov			c1o c2o
density functional	B1B95	c1ov	c1ov
	B3LYP	c1ov	c1ov	c1ov		c1ov	c1ov			c1ov c2ov
	PBEPBE									c1ov c2ov
Moller Plesset perturbation	MP2		c1ov		c1ov	c1ov	c1ov			c1o c2o

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Single point energy calculations (select basis sets)

		cc-pVDZ	cc-pVTZ	cc-pV(T+d)Z
Moller Plesset perturbation	MP2FC// HF/6-31G*	c1e	c1e	c1e
	MP2FC// B3LYP/6-31G*	c1e

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.