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 C₅H₁₁ (2-Methylbut-2-yl radical)

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	o
	PM3	ov
composite	G3	e
	G3B3	e
	G3MP2	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	cc-pV(T+d)Z
hartree fock	HF		ov	ov	ov	ov	ov	ov	ov		ov		ov	ov	ov	ov		ov
	ROHF		ov			ov	ov	ov	ov					ov	ov			ov
density functional	LSDA	ov			ov	ov			ov									ov
	BLYP		ov	ov	o	ov	o	ov	ov					ov	ov			ov
	B1B95																	ov
	B3LYP		ov	ov	ov	ov	ov	ov	ov		ov		ov	ov	ov	ov	ov	ov
	B3LYPultrafine																ov
	B3PW91		ov	ov	ov	ov	ov	ov			ov			ov	ov			ov
	mPW1PW91		ov			ov	ov	ov	ov					ov	ov			ov
	M06-2X			ov		ov
	PBEPBE											ov						ov
	PBE1PBE					ov
	HSEh1PBE		ov			ov		ov							ov
	TPSSh					ov		ov			ov				ov
	wB97X-D			ov		ov		ov		ov			ov	ov	ov		ov
	B97D3		ov			o		o		o		o	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	cc-pV(T+d)Z
Moller Plesset perturbation	MP2		ov	ov	ov	ov	o	ov	ov		ov		ov	ov
	MP2=FULL					ov	ov	ov	ov
	PMP2					o		o
	MP3							o
	MP3=FULL					ov		ov
	B2PLYP					ov									ov
	B2PLYP=FULLultrafine					ov
Configuration interaction	CID					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	cc-pV(T+d)Z
Quadratic configuration interaction	QCISD		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	cc-pV(T+d)Z

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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	B1B95		ov
	B3LYP	ov	ov	ov	ov	ov	ov			ov
	PBEPBE									ov
Moller Plesset perturbation	MP2	ov	ov	ov	ov	ov	ov			ov

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Single point energy calculations (select basis sets)

		cc-pVDZ	aug-cc-pVDZ	aug-cc-pVTZ
Moller Plesset perturbation	MP2FC// HF/6-31G*	e
	MP2FC// B3LYP/6-31G*	e
	MP2FC// MP2FC/6-31G*		e	e
	MP4// HF/6-31G*	e
Coupled Cluster	CCSD// HF/6-31G*	e
	CCSD(T)// HF/6-31G*	e
	CCSD// MP2FC/6-31G*			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.