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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IV.D.4. (XII.A.2.)

Comparison of experiment and theory for rHH

Species with coordinate rHH

Species	Name
H2	Hydrogen diatomic

The small prefix is the number of bonds with completed calculations.
Click on an entry for a histogram of the difference distribution.

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rms differences (calculated - experiment) in Å

Methods with predefined basis sets

semi-empirical	AM1	1 0.065
	PM3	2 0.043
composite	G2	2 0.011
	G3	2 0.011
	G3B3	2 0.001
	G3MP2	1 0.011
	G4	1 0.001
	CBS-Q	1 0.012

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rms differences (calculated - experiment) in Å

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	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
hartree fock	HF	2 0.029	2 0.007	2 0.007	2 0.011	1 0.011	2 0.009	2 0.009	2 0.010	2 0.006	2 0.009		1 0.007	1 0.006	2 0.007	2 0.007	2 0.008	2 0.007	2 0.007	2 0.008	1 0.014	1 0.007	1 0.007
density functional	LSDA	2 0.005	2 0.025	2 0.025	2 0.022	2 0.022	2 0.022	2 0.022	2 0.023	2 0.024	2 0.022	1 0.023	1 0.023	1 0.024	2 0.038	2 0.023	1 0.022	2 0.038	1 0.023	1 0.022		1 0.037	1 0.023
	BLYP	2 0.008	2 0.009	2 0.009	2 0.007	3 0.006	2 0.006	2 0.006	2 0.005	2 0.007	2 0.006	1 0.005	1 0.005	1 0.006	2 0.026	2 0.005	1 0.004	2 0.025	1 0.005	1 0.004		1 0.024	1 0.005
	B1B95	2 0.013	2 0.004	2 0.004	2 0.000	2 0.000	2 0.000	2 0.000	2 0.001	2 0.002	2 0.000	1 0.000	1 0.000	1 0.001	2 0.019	2 0.000	1 0.001	2 0.018	1 0.000	1 0.001		1 0.016	1 0.000
	B3LYP	2 0.013	2 0.005	2 0.005	2 0.001	2 0.001	2 0.001	2 0.001	2 0.000	1 0.003	2 0.001	2 0.001	1 0.001	1 0.002	2 0.020	2 0.001	2 0.000	1 0.019	2 0.001	2 0.000	1 0.027	1 0.018	1 0.001
	B3LYPultrafine	1 0.013	1 0.005	1 0.005	1 0.001	2 0.001	1 0.001	1 0.001	1 0.000	1 0.003	1 0.001	1 0.001	1 0.001	1 0.002	1 0.020	1 0.001	1 0.000	1 0.019	1 0.001	1 0.000		1 0.018	1 0.001
	B3PW91	1 0.013	2 0.006	2 0.006	2 0.002	2 0.002	2 0.002	2 0.002	2 0.002	1 0.004	2 0.002	1 0.003	1 0.003	1 0.004	2 0.019	2 0.003	1 0.002	2 0.019	1 0.003	1 0.002		1 0.018	1 0.003
	mPW1PW91	1 0.014	2 0.004	1 0.004	2 0.000	2 0.000	2 0.000	2 0.000	2 0.001	2 0.003	2 0.000	1 0.002	1 0.002	1 0.003	2 0.018	2 0.002	1 0.001	2 0.017	1 0.002	1 0.001		1 0.017	1 0.002
	M06-2X	1 0.019	1 0.000	2 0.000	1 0.005	1 0.005	1 0.005	1 0.005	1 0.004	1 0.001	1 0.005	2 0.003	1 0.003	1 0.001	1 0.013	1 0.003	1 0.004	1 0.013	1 0.003	1 0.005		1 0.013	1 0.003
	PBEPBE	1 0.007	2 0.012	1 0.012	1 0.009	2 0.009	2 0.009	2 0.009	2 0.009	2 0.010	2 0.009	2 0.009	1 0.009	1 0.010	2 0.028	2 0.009	1 0.009	1 0.027	2 0.009	1 0.009	1 0.035	1 0.026	1 0.009
	PBEPBEultrafine	1 0.007	1 0.012	1 0.012	1 0.009	2 0.009	1 0.008	1 0.008	1 0.009	1 0.010	1 0.008	1 0.009	1 0.009	1 0.010	1 0.028	1 0.009	1 0.009	1 0.027	1 0.009	1 0.009		1 0.026	1 0.009
	PBE1PBE	1 0.014	1 0.006	1 0.006	1 0.002	1 0.002	1 0.002	1 0.002	1 0.003	1 0.005	1 0.002	1 0.004	1 0.004	1 0.004	1 0.020	1 0.004	1 0.003	1 0.019	1 0.004	1 0.003		1 0.019	1 0.004
	HSEh1PBE	1 0.014	2 0.006	1 0.006	1 0.002	2 0.002	1 0.002	1 0.002	1 0.002	1 0.005	1 0.002	1 0.003	1 0.003	1 0.004	1 0.020	1 0.004	1 0.003	1 0.019	1 0.004	1 0.003		1 0.019	1 0.004
	TPSSh		1 0.002	1 0.002	1 0.003	1 0.003	1 0.002	1 0.002	1 0.000		1 0.002			1 0.001	1 0.015	1 0.005		1 0.015	1 0.001			1 0.014	1 0.001
	wB97X-D			1 0.005		1 0.000		1 0.001		1 0.003				1 0.003	1 0.001	1 0.002			1 0.002			1 0.016	1 0.002
	B97D3		1 0.007			1 0.003		1 0.003		1 0.004		1 0.003		1 0.004		1 0.003			1 0.003			1 0.020	2 0.003
		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	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	1 0.018	2 0.000	2 0.000	2 0.004	3 0.004	2 0.008	2 0.008	3 0.004	2 0.003	2 0.008	2 0.005	1 0.004	1 0.004	2 0.013	2 0.004	2 0.005	2 0.013	2 0.004	2 0.005	2 0.025	1 0.013	1 0.004
	MP2=FULL	1 0.018	2 0.000	1 0.000	1 0.004	2 0.004	2 0.008	2 0.008	1 0.004	1 0.003	1 0.008	1 0.005	1 0.004	1 0.004	1 0.013	1 0.004	2 0.005	2 0.014	2 0.004	1 0.005	1 0.025	1 0.013	1 0.004
	MP3	1 0.011	1 0.004	1 0.004	1 0.000	2 0.000	1 0.006	1 0.006	1 0.000	1 0.001	1 0.006	1 0.002	1 0.002	1 0.002	1 0.016	1 0.002	1 0.003	1 0.017	1 0.001	1 0.003		1 0.017	1 0.001
	MP3=FULL					1 0.000		1 0.006						1 0.002	1 0.016	1 0.002						1 0.017	1 0.001
	MP4	1 0.008	2 0.006	1 0.006	1 0.003	2 0.003	1 0.004	1 0.004	2 0.003	1 0.001	1 0.004	1 0.001	1 0.000	1 0.000	1 0.018	1 0.000	1 0.001	1 0.019	1 0.000	1 0.001		1 0.018	1 0.000
	MP4=FULL	1 0.008	1 0.006	1 0.006	1 0.003	1 0.003	1 0.004	1 0.004	1 0.003	1 0.001	1 0.004	1 0.001	1 0.000		1 0.018	1 0.000	1 0.001	1 0.019	1 0.000	1 0.001		1 0.018	1 0.000
	B2PLYP	1 0.016	1 0.002	1 0.002	1 0.002	1 0.002	1 0.003	1 0.003	1 0.002	1 0.000	1 0.003	1 0.001	1 0.001	1 0.001	1 0.017	1 0.001	1 0.002	1 0.016	1 0.001	1 0.002		1 0.016	1 0.001
	B2PLYP=FULL	1 0.016	1 0.002	1 0.002	1 0.002	1 0.002	1 0.003	1 0.003	1 0.002	1 0.000	1 0.003			1 0.001	1 0.017	1 0.001		1 0.016	1 0.001			1 0.016	1 0.001
	B2PLYP=FULLultrafine	1 0.016	1 0.002	1 0.002	1 0.002	2 0.002	1 0.003	1 0.003	1 0.002	1 0.000	1 0.003			1 0.001	2 0.017	2 0.001		1 0.016	2 0.001			1 0.016	1 0.001
Configuration interaction	CID	1 0.007	1 0.008	1 0.008	1 0.004	2 0.004	1 0.004	1 0.004	2 0.005	1 0.001	1 0.004	1 0.000	1 0.001		1 0.019	2 0.001	1 0.000	1 0.019	1 0.001	1 0.000		1 0.019	1 0.001
	CISD	1 0.007	2 0.008	1 0.008	1 0.004	2 0.005		1 0.003	1 0.005	1 0.002	1 0.003	1 0.001	1 0.001		1 0.019	2 0.001	1 0.000	1 0.020	1 0.001	1 0.000		1 0.019	1 0.001
		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	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD	1 0.007	2 0.008	2 0.007	1 0.004	2 0.005	2 0.003	2 0.003	2 0.005	2 0.002	1 0.003	1 0.001	1 0.001	1 0.001	2 0.019	2 0.001	1 0.000	1 0.020	1 0.001	1 0.000		1 0.019	1 0.001
	QCISD(T)	1 0.007	1 0.008	1 0.008	1 0.005	2 0.005	2 0.003	2 0.003	2 0.005	1 0.002	1 0.003	1 0.001	1 0.001	1 0.001	2 0.019	2 0.001	1 0.000	1 0.020	1 0.002	1 0.001		1 0.020	1 0.002
	QCISD(T)=FULL					1 0.005		1 0.003							1 0.020	1 0.001	1 0.000	1 0.020	1 0.002	1 0.001		1 0.020	1 0.002
Coupled Cluster	CCD	1 0.007	2 0.008	1 0.008	1 0.004	2 0.004	2 0.004	2 0.004	2 0.005	1 0.001	1 0.004	2 0.000	1 0.001	1 0.000	2 0.019	2 0.001	2 0.000	2 0.020	2 0.001	2 0.000		1 0.019	1 0.001
	CCSD		2 0.008	1 0.008	1 0.004	2 0.005	2 0.003	2 0.003	2 0.005	1 0.002	1 0.003	2 0.001	1 0.001	1 0.001	2 0.019	2 0.001	1 0.000	2 0.020	2 0.001	1 0.000		1 0.019	1 0.001
	CCSD=FULL		1 0.008	1 0.008	1 0.004	1 0.004	1 0.003	1 0.003	1 0.005	1 0.002	1 0.003	1 0.001	1 0.001	1 0.001	1 0.019	1 0.001	1 0.000	1 0.020	1 0.001	1 0.000		1 0.019	1 0.001
	CCSD(T)		2 0.008	1 0.008	1 0.005	2 0.005	2 0.003	2 0.003	2 0.005		1 0.003	2 0.001	1 0.001	1 0.001	2 0.019	2 0.001	1 0.000	2 0.020	2 0.002	1 0.001		1 0.020	1 0.002
	CCSD(T)=FULL		1 0.008	1 0.008	1 0.005	1 0.005	1 0.003	1 0.003	1 0.005	1 0.002	1 0.003	1 0.001	1 0.001	1 0.001	1 0.020	1 0.001	1 0.000	1 0.020	1 0.002	1 0.001		1 0.020	1 0.002
		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	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ

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rms differences (calculated - experiment) in Å

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	2 0.010	2 0.010	2 0.010	2 0.010	2 0.010	2 0.010			1 0.007
density functional	LSDA	1 0.023	1 0.023	1 0.023	1 0.023	1 0.023	1 0.023
	BLYP	1 0.007	1 0.007	1 0.005	1 0.005	1 0.007	1 0.007
	B1B95	2 0.001	1 0.001	1 0.001	1 0.001	1 0.000	1 0.000
	B3LYP	2 0.002	2 0.002	2 0.000	2 0.000	2 0.002	2 0.002			1 0.001
	B3LYPultrafine	1 0.002	1 0.002	1 0.000	1 0.000	1 0.002	1 0.002
	B3PW91	1 0.003	1 0.003	1 0.002	1 0.002	1 0.003	1 0.003
	mPW1PW91	1 0.001	1 0.001	1 0.001	1 0.001	1 0.001	1 0.001
	M06-2X	1 0.004	1 0.004	1 0.004	1 0.004	1 0.004	1 0.004
	PBEPBE	1 0.010	1 0.010	1 0.009	1 0.009	1 0.010	1 0.010			1 0.009
	PBEPBEultrafine	1 0.010	1 0.010	1 0.009	1 0.009	1 0.010	1 0.010
	PBE1PBE	1 0.003	1 0.003	1 0.003	1 0.003	1 0.003	1 0.003
	HSEh1PBE	1 0.003	1 0.003	1 0.002	1 0.002	1 0.003	1 0.003
Moller Plesset perturbation	MP2	2 0.003	2 0.003	2 0.004	2 0.004	2 0.003	2 0.003			1 0.004
	MP2=FULL	1 0.003	1 0.003	1 0.004	1 0.004	1 0.003	1 0.003
	MP3	1 0.001	1 0.001	1 0.000	1 0.000	1 0.001	1 0.001
	MP4	1 0.004	1 0.004	1 0.003	1 0.003	1 0.004	1 0.004
	MP4=FULL	1 0.004	1 0.004	1 0.003	1 0.003	1 0.004	1 0.004
	B2PLYP	1 0.001	1 0.001	1 0.002	1 0.002	1 0.001	1 0.001
Configuration interaction	CID	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
	CISD	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
Quadratic configuration interaction	QCISD	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
	QCISD(T)	1 0.006	1 0.006	1 0.005	1 0.005	1 0.006	1 0.006
Coupled Cluster	CCD	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
	CCSD	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
	CCSD=FULL	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005	1 0.005
	CCSD(T)	1 0.006	1 0.006	1 0.005	1 0.005	1 0.006	1 0.006
	CCSD(T)=FULL	1 0.006	1 0.006	1 0.005	1 0.005	1 0.006	1 0.006

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.