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 aOCO

Species with coordinate aOCO

Species	Name
HCOOH	Formic acid
CH3COOH	Acetic acid
CH3OCHO	methyl formate
C4H2O3	Maleic Anhydride
C3H8O2	Methane, dimethoxy-
C3H6O3	1,3,5-Trioxane
CO2-	Carbon dioxide anion
CO2	Carbon dioxide
CO2+	Carbon dioxide cation
C4H8O2	Ethyl acetate
C2H2O4	Oxalic Acid
CH2O2	Dioxirane
C4H8O2	1,3-Dioxane
C3H2O3	vinylene carbonate
CHOOCHO	diformyl ether
HOCO	Hydrocarboxyl radical
HOCO+	Hydrocarboxyl cation
C2H4O4	Formic acid dimer

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

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rms differences (calculated - experiment) in degrees

Methods with predefined basis sets

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rms differences (calculated - experiment) in degrees

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-pCVDZ	cc-pCVTZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
hartree fock	HF	1.819	1.319	1.319	1.419	0.919	1.019	0.814	1.019	1.119	1.019	1.011	0.02	1.218	1.019	1.019	1.212	1.018	1.117	1.111				0.12	0.44	1.019
density functional	LSDA	2.86	2.011	0.99	1.26	1.58	1.411	1.111	1.48	1.311	1.411	0.02		1.37	1.511	1.211	0.22	0.89	0.56	0.22
	BLYP	5.818	1.019	1.018	1.118	10.019	2.119	0.718	0.717	0.619	0.719	0.67		0.511	0.718	0.717		0.514	0.511						0.64	0.74
	B1B95	3.918	1.118	1.118	1.018	0.719	0.818	0.818	0.718	0.818	0.817	0.77		0.611	0.818	0.818	0.12	0.817	0.916	0.12					0.64	0.53
	B3LYP	4.419	1.019	1.019	1.019	0.619	0.619	0.719	0.619	0.717	0.719	0.610	0.22	0.718	1.019	0.719	0.811	1.018	0.719	0.811				0.12	0.64	0.64
	B3LYPultrafine		1.011			0.619	0.511	0.513	0.511		0.57	0.77		0.511	0.511	0.514		0.511	0.819						0.64	0.64
	B3PW91	5.316	1.019	1.019	0.919	0.719	0.719	0.719	0.719	0.717	0.719	0.67		0.511	0.719	0.719		0.514	0.714						0.54	0.64
	mPW1PW91	4.616	1.019	1.016	1.019	0.719	0.719	0.719	0.719	0.719	0.819	0.67		0.511	0.719	0.718		0.516	0.511						0.54	0.64
	M06-2X	1.911	1.111	1.319	1.011	0.916	0.611	0.711	0.611	0.611	0.814	0.99		0.711	0.611	0.814		0.711	0.914						0.64	0.64
	PBEPBE	6.116	1.218	1.216	1.116	0.819	0.719	0.719	0.719	0.719	0.719	0.59	0.32	0.511	1.019	0.619	0.52	0.413	0.514	0.52				0.22	0.64	0.64
	PBEPBEultrafine		1.311			0.715	0.711	0.511	0.611		0.47	0.57		0.511	0.711	0.611		0.511	0.511						0.64	0.64
	PBE1PBE	5.311	1.111	1.111	0.811	0.816	0.611	0.511	0.511	0.611	0.611	0.67		0.511	0.611	0.511		0.511	0.511						0.54	0.64
	HSEh1PBE	5.311	1.116	1.111	0.811	0.816	0.611	0.816	0.611	0.611	0.611	0.67		0.611	0.611	0.816		0.511	0.511						0.54	0.64
	TPSSh	6.611	1.211	1.211	0.811	9.719	0.711	9.719	0.511	0.611	9.719	0.77		0.611	0.611	9.719	0.69	0.611	0.611	0.77					0.64	0.64
	wB97X-D	3.111	1.011	10.019	0.911	10.319	0.511	10.219	0.511	10.319	0.611	0.67		10.319	10.219	10.319	0.59	0.511	10.319	0.46					0.54	0.54
	B97D3	1.79	1.119	0.99	0.99	0.719	0.79	0.719	0.69	0.619	0.79	0.619		0.619	0.69	0.719	0.69	0.59	0.619	0.66					0.64	0.46
		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-pCVDZ	cc-pCVTZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	2.217	0.919	0.918	1.319	10.019	0.619	0.518	10.119	0.519	0.719	0.67	0.22	0.518	0.519	3.019	0.59	0.618	0.716	0.59				0.12	0.44	0.54
	MP2=FULL	2.216	0.818	0.916	1.416	3.119	0.619	0.719	0.519	0.617	0.718	0.67		0.413	0.518	3.118	0.59	0.714	0.515	0.67				0.12	0.54	0.64
	MP3					0.814		11.316				0.66		0.59	0.49	0.59									0.12	0.32
	MP3=FULL		0.67	0.67	1.07	10.517	0.57	10.617	0.47	0.57	0.77	0.75		0.58	0.48	0.58		0.65	0.32						0.22
	MP4		0.910			0.613				0.59		0.66		0.48	0.49	0.49		0.57	0.55
	MP4=FULL		0.89			0.59				0.49		0.65			0.49	0.48		0.55	0.43
	B2PLYP	2.011	0.911	0.911	0.911	0.716	0.511	0.511	0.411	0.58	0.614	0.67		0.511	0.411	10.119		0.511	0.514						0.54	0.55
	B2PLYP=FULL	2.011	1.111	0.99	1.09	0.511	0.511	0.511	0.59	0.511	0.511	0.67		0.511	0.411	0.511		0.511	0.511						0.54	0.64
	B2PLYP=FULLultrafine	2.311	0.911	0.911	0.911	0.37	0.511	0.511	0.511	0.511	0.611	0.67		0.511	0.39	0.49		0.511	0.57				0.22		0.54	0.64
Configuration interaction	CID		1.112	1.112	1.412	1.214			0.912			0.76			0.56	0.66									0.32
	CISD		1.111	1.012	1.412	1.214			0.912			0.76			0.56	0.66									0.32
		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-pCVDZ	cc-pCVTZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD	3.62	1.313	0.912	1.612	0.717	0.713	0.814	0.614	0.415	0.713	0.33		0.59	0.612	0.613		0.59	0.610						0.22
	QCISD(T)					0.511		0.72	0.35	0.32		0.12		0.59	0.410	0.23		0.57	0.13						0.22
	QCISD(T)=FULL					0.45		0.68				0.74			0.47	0.57	0.01	0.32	0.21	0.01
	QCISD(TQ)					0.02		0.02				0.12			0.22	0.12		0.12
	QCISD(TQ)=FULL					0.11		0.11							0.31			0.11
Coupled Cluster	CCD	3.82	0.912	0.912	1.412	0.815	0.712	0.812	0.712	0.511	0.611	0.66		0.59	0.712	0.410		0.58	0.34						0.22	0.32
	CCSD					0.716	0.55	0.76	0.45	0.46	0.713	0.33		0.411	0.411	0.511	0.02	0.17	0.611	0.02					0.22
	CCSD=FULL					0.611					0.711	0.66		0.59	0.49	0.612	0.12	0.59	0.68	0.02					0.22
	CCSD(T)					0.510	0.58	0.77	0.48	0.37	0.33	0.66	0.12	0.25	0.49	0.48	0.02	0.56	0.13	0.02	0.22	0.12			0.22
	CCSD(T)=FULL					0.59						0.65		0.58	0.48	0.58	0.02	0.56	0.12	0.02	0.22	0.12
		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-pCVDZ	cc-pCVTZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ

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rms differences (calculated - experiment) in degrees

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	1.519	1.019	1.519	1.019	1.419	1.419			10.419
density functional	BLYP									0.67
	B1B95	0.98	0.78							0.77
	B3LYP	1.019	0.619	1.119	0.619	1.019	1.019			10.219
	B3LYPultrafine									0.67
	B3PW91									0.67
	mPW1PW91									0.57
	M06-2X									0.77
	PBEPBE									10.119
	PBEPBEultrafine									0.57
	PBE1PBE									0.57
	HSEh1PBE									0.67
	TPSSh									0.67
	wB97X-D	0.811	0.411	1.111	0.511	0.911	0.911			0.67
	B97D3									0.67
Moller Plesset perturbation	MP2	1.319	0.519	1.419	0.719	1.219	1.219			10.119
	MP2=FULL									0.57
	MP3									0.64
	MP3=FULL									0.64
	MP4=FULL									0.64
	B2PLYP									0.67
	B2PLYP=FULL									0.67
	B2PLYP=FULLultrafine									0.67
Configuration interaction	CID									0.84
	CISD									0.84
Quadratic configuration interaction	QCISD									0.41
	QCISD(T)									0.64
	QCISD(T)=FULL									0.64
Coupled Cluster	CCD									0.64
	CCSD									0.64
	CCSD=FULL									0.74
	CCSD(T)									0.73
	CCSD(T)=FULL									0.64

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.