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

---

NIST policy on privacy, security, and accessibility.

---

© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

III.F.2.

Completed calculations for C₂H₂ (Acetylene)

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.

---

Methods with predefined basis sets

composite	G1	e
	G2MP2	e
	G2	e
	G3	e
	G3B3	e
	G3MP2	e
	G4	e
	CBS-Q	e

---

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)	6-311+G(3df,2pd)	TZVP	cc-pVDZ	cc-pVTZ	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
hartree fock	HF	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov			ov	ov	ov
density functional	LSDA											ov	ov	ov			ov		ov	ov
	BLYP	ov	ov	ov	ov	ov	ov	ov	ov	ov	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	ov	ov	ov	ov	ov	ov	ov				ov	ov
	B3LYP	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov			ov	ov	ov
	B3LYPultrafine	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov					ov	ov
	B3PW91	ov	ov	ov	ov	ov	ov	ov	ov	ov	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	ov	ov	ov	ov	ov	ov	ov				ov	ov
	M06-2X	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov					ov	ov
	PBEPBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov			ov	ov	ov
	PBEPBEultrafine	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov					ov	ov
	PBE1PBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov					ov	ov
	HSEh1PBE	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov					ov	ov
	TPSSh	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	ov	ov	ov	ov					ov	ov
	wB97X-D	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	ov	ov	ov	ov					ov	ov
	B97D3	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov	ov	ov	ov	ov					ov	ov
		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)	6-311+G(3df,2pd)	TZVP	cc-pVDZ	cc-pVTZ	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	MP2=FULL	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	MP3	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	MP3=FULL					ov		ov
	MP4	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	o	ov	ov	ov	ov	ov	ov
	MP4=FULL	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	B2PLYP	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov		ov	ov						ov	ov
	B2PLYP=FULL	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov		ov	ov	ov		ov	ov						ov	ov
	B2PLYP=FULLultrafine					ov													ov
Configuration interaction	CID	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	CISD	ov	o	ov	ov	ov	o	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
		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)	6-311+G(3df,2pd)	TZVP	cc-pVDZ	cc-pVTZ	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	QCISD(T)	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	QCISD(TQ)	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	dnf		ov	ov	ov	ov	ov	dnf
Coupled Cluster	CCD	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	CCSD	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	CCSD=FULL	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	CCSD(T)	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
	CCSD(T)=FULL	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov	ov
		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)	6-311+G(3df,2pd)	TZVP	cc-pVDZ	cc-pVTZ	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ

---

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	LSDA	ov	ov	ov	ov	ov	ov
	BLYP	ov	ov	ov	ov	ov	ov			ov
	B1B95	ov	ov	ov	ov	ov	ov			ov
	B3LYP	ov	ov	ov	ov	ov	ov			ov
	B3LYPultrafine	ov	ov	ov	ov	ov	ov			ov
	B3PW91	ov	ov	ov	ov	ov	ov			ov
	mPW1PW91	ov	ov	ov	ov	ov	ov			ov
	M06-2X	ov	ov	ov	ov	ov	ov			ov
	PBEPBE	ov	ov	ov	ov	ov	ov			ov
	PBEPBEultrafine	ov	ov	ov	ov	ov	ov			ov
	PBE1PBE	ov	ov	ov	ov	ov	ov			ov
	HSEh1PBE	ov	ov	ov	ov	ov	ov			ov
	TPSSh									ov
	wB97X-D	ov	ov	ov	ov	ov	ov			ov
	B97D3									ov
Moller Plesset perturbation	MP2	ov	ov	ov	ov	ov	ov			ov
	MP2=FULL	ov	ov	ov	ov	ov	ov			ov
	MP3	ov	ov	ov	ov	ov	ov
	MP4	ov	ov	ov	ov	ov	ov
	MP4=FULL	ov	ov	ov	ov	ov	ov
	B2PLYP									ov
	B2PLYP=FULL									ov
Configuration interaction	CID	ov	ov	ov	ov	ov	ov
	CISD	ov	ov	ov	ov	ov	ov
Quadratic configuration interaction	QCISD	ov	ov	ov	ov	ov	ov
	QCISD(T)	ov	ov	ov	ov	ov	ov
	QCISD(TQ)	ov	ov	ov	ov	ov	ov
Coupled Cluster	CCD	ov	ov	ov	ov	ov	ov
	CCSD	ov	ov	ov	ov	ov	ov
	CCSD=FULL	ov	ov	ov	ov	ov	ov
	CCSD(T)	ov	ov	ov	ov	ov	ov
	CCSD(T)=FULL	ov	ov	ov	ov	ov	ov

---

Single point energy calculations (select basis sets)

		6-311+G(3df,2p)	cc-pVDZ	cc-pVTZ	aug-cc-pVDZ	aug-cc-pVTZ	cc-pV(T+d)Z
Moller Plesset perturbation	MP2FC// HF/6-31G*	e	e	e	e	e	e
	MP2FC// B3LYP/6-31G*	e	e	e	e	e	e
	MP2FC// MP2FC/6-31G*	e	e	e	e	e	e
	MP4// HF/6-31G*	e		e			e
	MP4// B3LYP/6-31G*		e	e			e
	MP4// MP2/6-31G*	e		e			e
Coupled Cluster	CCSD// HF/6-31G*	e	e	e	e	e	e
	CCSD(T)// HF/6-31G*	e	e	e	e	e	e
	CCSD// B3LYP/6-31G*	e	e	e	e		e
	CCSD(T)// B3LYP/6-31G*	e	e	e	e		e
	CCSD(T)//B3LYP/6-31G(2df,p)			e			e
	CCSD// MP2FC/6-31G*	e	e	e	e	e	e
	CCSD(T)// MP2FC/6-31G*	e	e	e	e	e	e

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.