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 rCN

Species with coordinate rCN

Species	Name
H2NCH2COOH	Glycine
CH3CH(NH2)COOH	Alanine
NH2CONH2	Urea
CH3CONH2	Acetamide
C6H5NH2	aniline
CH3CSNH2	Ethanethioamide
C4H4N2O2	Uracil
C3H7NO	dimethylformamide
CH3NH2	methyl amine
HCN	Hydrogen cyanide
CH3CH2NH2	Ethylamine
CH3CN	Acetonitrile
CHONH2	formamide
HNCO	Isocyanic acid
CH2NOH	formaldoxime
N(CH3)3	Trimethylamine
CH3NO2	Methane, nitro-
C(CH3)3NH2	2-Propanamine, 2-methyl-
CH3CH(CH3)CN	Propanenitrile, 2-methyl-
C6H5NO2	Nitrobenzene
C6H5CN	phenyl cyanide
C2H5CN	ethyl cyanide
C3H3N	acrylonitrile
C2H8N2	Ethylenediamine
CH3CHNOH	Acetaldoxime
C3H2N2	Malononitrile
C4H5N	Pyrrole
C5H9N	Pentanenitrile
C4H4N2	Succinonitrile
C5H5N	Pyridine
C5H11N	Piperidine
CHSNH2	thioformamide
HCONHCH3	N-methylformamide
C4H9N	Pyrrolidine
CH3NHCH3	Dimethylamine
HNCNH	diiminomethane
C2H5N	Aziridine
CH2N2	diazirine
C3H4N2	1H-Pyrazole
C3H3NO	Isoxazole
C3H4N2	1H-Imidazole
C2H2N2O	Furazan
C3H3NO	Oxazole
C2H3N3	1H-1,2,4-Triazole
C2H2N2S	1,3,4-Thiadiazole
C2H4O3	trioxolane124
C4H4N2	Pyridazine
C4H4N2	1,3-Diazine
C4H4N2	Pyrazine
C3H3N3	1,3,5-Triazine
CH2NN	diazomethane
CF3CN	Acetonitrile, trifluoro-
NH2CN	cyanamide
CH(CN)3	tricyanomethane
C2N2	Cyanogen
C3H7N	Azetidine
BrCN	Cyanogen bromide
ClCN	chlorocyanogen
ICN	Cyanogen iodide
HCNO	fulminic acid
CH3NC	methyl isocyanide
C4H5N	(E)-2-Butenenitrile
C5H9N	Propanenitrile, 2,2-dimethyl-
C3H7N	Cyclopropylamine
CH3NO	nitrosomethane
HCCCN	Cyanoacetylene
C4N2	2-Butynedinitrile
FCN	Cyanogen fluoride
CH2NCH3	N-methylmethanimine
CH2NH	Methanimine
CN	Cyano radical
HNCS	Isothiocyanic acid
CH3SO2NH2	methanesulfonamide
C2H6N2O2	Dimethylnitroamine
C5H7N	Cyclobutanecarbonitrile
C4H5N	Cyclopropanecarbonitrile
C4H5NO	Isoxazole, 5-methyl-
HNC	hydrogen isocyanide
C5H5N	Bicyclo[1.1.0]butane-1-carbonitrile
C(CN)4	tetracyanomethane
C4H5NO	3-Methylisoxazole
C2H3NO	Nitrosoethylene
ZnCN	Zinc monocyanide

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	74 0.049
	PM3	168 0.048
	PM6	135 0.127
composite	G2	137 0.117
	G3	144 0.114
	G3B3	145 0.113
	G3MP2	14 0.020
	G4	132 0.043
	CBS-Q	112 0.129
molecular mechanics	DREIDING	6 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)	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	cc-pCVQZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
hartree fock	HF	155 0.116	148 0.119	148 0.116	148 0.120	313 0.131	150 0.108	144 0.110	151 0.107	148 0.108	151 0.107	109 0.026	140 0.112	150 0.108	148 0.108	57 0.027	148 0.108	147 0.109	41 0.026	2 0.031	6 0.014	7 0.024	3 0.027		8 0.016	15 0.021	136 0.046
	ROHF		5 0.023	5 0.023	4 0.019	4 0.030	4 0.030	4 0.030	4 0.035	3 0.033	2 0.039	2 0.031	3 0.036	4 0.028	4 0.037	3 0.037	3 0.027	3 0.036	3 0.037		2 0.034	2 0.044	2 0.045			1 0.033	1 0.043
density functional	LSDA	42 0.132	65 0.015	48 0.064	43 0.092	66 0.060	65 0.060	65 0.060	63 0.060	63 0.060	63 0.058	2 0.012	20 0.107	65 0.063	65 0.058		65 0.062	37 0.076		1 0.019	3 0.006	4 0.006	3 0.007			1 0.009	1 0.003
	BLYP	154 0.152	151 0.130	126 0.135	148 0.133	254 0.041	149 0.117	148 0.118	125 0.127	147 0.117	146 0.116	24 0.010	56 0.074	147 0.119	151 0.115		111 0.056	40 0.082		1 0.002	3 0.015	4 0.002	3 0.002			15 0.015	15 0.006
	B1B95	147 0.132	147 0.110	150 0.114	150 0.120	152 0.107	149 0.108	143 0.110	150 0.107	148 0.108	144 0.039	25 0.013	56 0.065	149 0.108	151 0.107	2 0.009	142 0.042	110 0.046	2 0.008	1 0.017	3 0.002	4 0.012	3 0.014			13 0.007	15 0.013
	B3LYP	155 0.137	148 0.123	149 0.118	149 0.125	151 0.041	149 0.112	150 0.112	149 0.111	86 0.146	156 0.108	98 0.010	137 0.116	150 0.111	150 0.111	41 0.011	114 0.129	150 0.112	35 0.009	2 0.009	3 0.002	4 0.010	3 0.011		8 0.005	15 0.005	15 0.009
	B3LYPultrafine		47 0.089			142 0.042	46 0.073	80 0.055	47 0.071		24 0.008	24 0.010	54 0.068	56 0.069	111 0.046		56 0.069	127 0.043		1 0.010	2 0.002	3 0.009	2 0.011			15 0.005	15 0.009
	B3PW91	85 0.174	148 0.121	148 0.117	147 0.123	147 0.041	148 0.110	123 0.121	146 0.110	86 0.144	144 0.110	24 0.010	56 0.066	148 0.110	149 0.109		111 0.048	60 0.061		1 0.014	3 0.001	4 0.009	3 0.011			15 0.006	15 0.010
	mPW1PW91	95 0.162	147 0.120	97 0.143	151 0.121	146 0.041	148 0.109	148 0.109	149 0.108	147 0.109	144 0.109	24 0.012	56 0.065	147 0.110	118 0.122		127 0.045	56 0.063		1 0.016	3 0.002	4 0.012	3 0.014			15 0.007	15 0.012
	M06-2X	57 0.099	57 0.072	154 0.041	56 0.074	135 0.114	56 0.063	56 0.063	57 0.063	56 0.063	79 0.052	105 0.324	56 0.065	56 0.065	79 0.053		56 0.065	78 0.053		1 0.013	3 0.008	4 0.017	3 0.019			15 0.006	15 0.012
	PBEPBE	87 0.183	152 0.125	90 0.153	88 0.166	144 0.045	144 0.115	144 0.116	145 0.114	147 0.113	146 0.197	152 0.161	56 0.070	138 0.118	146 0.113	2 0.004	63 0.068	90 0.053	2 0.005	2 0.006	3 0.013	4 0.003	3 0.002		8 0.004	15 0.014	15 0.006
	PBEPBEultrafine		48 0.097			180 0.040	46 0.077	47 0.076	47 0.074		24 0.012	24 0.009	54 0.071	56 0.073	57 0.066		56 0.072	54 0.068		1 0.004	2 0.013	3 0.003	2 0.001			15 0.014	15 0.006
	PBE1PBE	57 0.109	56 0.010	57 0.058	57 0.078	132 0.115	56 0.064	56 0.063	57 0.063	56 0.063	56 0.061	24 0.012	56 0.065	56 0.066	57 0.062		56 0.066	56 0.062		1 0.016	3 0.001	4 0.011	3 0.012			15 0.007	15 0.011
	HSEh1PBE	57 0.110	135 0.126	57 0.058	57 0.078	138 0.113	56 0.064	134 0.118	57 0.063	56 0.063	56 0.062	24 0.012	56 0.065	56 0.066	135 0.114		56 0.066	56 0.063		1 0.016	3 0.001	4 0.011	3 0.013			15 0.007	15 0.011
	TPSSh	28 0.164	56 0.085	56 0.062	55 0.087	143 0.048	54 0.068	142 0.048	55 0.066	27 0.094	124 0.049	24 0.008	54 0.069	54 0.071	143 0.047	18 0.007	54 0.071	54 0.066	18 0.008	1 0.009	3 0.006	4 0.005	3 0.006			15 0.007	15 0.006
	wB97X-D	38 0.127	38 0.090	147 0.044	37 0.094	143 0.046	37 0.078	142 0.046	38 0.076	145 0.045	37 0.075	24 0.012	142 0.047	142 0.047	146 0.045	23 0.011	37 0.081	145 0.045	22 0.011	1 0.015	3 0.002	3 0.014	3 0.014			15 0.005	15 0.011
	B97D3	25 0.185	135 0.066	27 0.091	26 0.135	134 0.052	25 0.103	133 0.052	26 0.100	133 0.051	25 0.099	141 0.045	133 0.048	25 0.108	134 0.050	16 0.009	25 0.108	132 0.046	16 0.009	1 0.004	3 0.011	3 0.001	3 0.002	1 0.004		15 0.011	98 0.053
		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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	cc-pCVQZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	92 0.171	152 0.125	151 0.122	151 0.130	290 0.085	150 0.111	258 0.086	245 0.090	148 0.110	148 0.109	23 0.015	140 0.113	150 0.111	185 0.037	28 0.019	112 0.131	117 0.127	27 0.019	2 0.012	7 0.031	8 0.034	3 0.040		16 0.004	14 0.026	14 0.018
	MP2=FULL	89 0.174	121 0.140	98 0.149	97 0.161	192 0.098	123 0.122	124 0.122	150 0.108	86 0.143	108 0.126	23 0.014	55 0.066	118 0.125	140 0.112	28 0.019	73 0.063	86 0.051	26 0.017	2 0.012	7 0.031	8 0.034	3 0.041		8 0.003	14 0.025	14 0.016
	ROMP2	2 0.088	1 0.062	2 0.050	1 0.068	1 0.035	1 0.035	1 0.035	1 0.027	1 0.027	1 0.027	1 0.005	1 0.021	1 0.040	1 0.021		1 0.040
	MP3					144 0.112		137 0.047	1 0.006			19 0.014	49 0.069	49 0.070	50 0.066					1 0.013	3 0.025	4 0.032	3 0.039	1 0.022		10 0.012	9 0.016
	MP3=FULL		33 0.099	33 0.077	33 0.103	139 0.046	32 0.082	127 0.048	33 0.080	32 0.082	32 0.079	19 0.015	49 0.069	49 0.070	48 0.067		32 0.087	32 0.081		1 0.018	3 0.026	4 0.033	3 0.041			8 0.013	7 0.021
	MP4	4 0.068	80 0.034	3 0.031	4 0.018	81 0.018			9 0.018	55 0.017	4 0.012	11 0.011	45 0.014	40 0.024	53 0.015		44 0.024	40 0.014		1 0.003	1 0.025	2 0.012	1 0.008	1 0.008		6 0.027	8 0.014
	MP4=FULL		45 0.031			43 0.018			1 0.020	44 0.017		16 0.009		43 0.024	45 0.012		44 0.023	41 0.011			1 0.024	2 0.010	1 0.006	1 0.006		7 0.024	6 0.007
	B2PLYP	53 0.122	54 0.083	54 0.063	53 0.087	151 0.110	52 0.068	52 0.068	53 0.066	51 0.067	75 0.054	24 0.008	52 0.069	52 0.071	146 0.045		52 0.071	83 0.052		1 0.010	3 0.012	4 0.001	3 0.002			15 0.011	15 0.006
	B2PLYP=FULL	53 0.122	54 0.083	54 0.063	53 0.087	53 0.067	52 0.068	52 0.068	53 0.066	52 0.067	52 0.064	24 0.008	52 0.069	52 0.071	53 0.065		52 0.071	52 0.065		1 0.011	3 0.012	4 0.002	3 0.003			15 0.011	15 0.007
	B2PLYP=FULLultrafine	37 0.141	39 0.097	39 0.073	38 0.101	188 0.532	37 0.080	37 0.080	38 0.078	37 0.079	37 0.076	24 0.008	37 0.081	123 0.661	124 0.652		37 0.084	123 0.653		1 0.011	2 0.012	2 0.002	2 0.003	5 0.003		15 0.011	15 0.007
Configuration interaction	CID		87 0.157	87 0.153	87 0.160	122 0.140	3 0.013	3 0.013	90 0.136	5 0.013	4 0.012	22 0.020		25 0.010	23 0.021					1 0.021	3 0.024	4 0.032	3 0.039	1 0.030		13 0.010	11 0.020
	CISD	4 0.107	92 0.153	87 0.153	87 0.160	121 0.120	7 0.013	3 0.012	86 0.139	5 0.013	4 0.011	22 0.018		25 0.008	23 0.019					1 0.021	3 0.011	4 0.023	3 0.029	1 0.029		13 0.007	9 0.019
		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	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ	cc-pCVQZ	aug-cc-pCVTZ	Sadlej_pVTZ	daug-cc-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD	13 0.380	135 0.136	86 0.159	89 0.166	142 0.113	93 0.140	91 0.142	110 0.126	110 0.126	87 0.140	22 0.008	50 0.069	97 0.137	90 0.049		53 0.070	72 0.055		2 0.008	3 0.012	4 0.004	3 0.008			13 0.013	10 0.005
	QCISD(T)					79 0.076		2 0.015	37 0.079	5 0.012		15 0.006	51 0.070	49 0.075	50 0.067		42 0.082	39 0.007			1 0.019	2 0.004	1 0.001	1 0.006		12 0.018	11 0.006
	QCISD(T)=FULL					36 0.081		37 0.080	1 0.011			16 0.005		36 0.086	34 0.008	15 0.005	35 0.088	31 0.007	11 0.004		1 0.018	2 0.003	1 0.001			8 0.018	7 0.003
	QCISD(TQ)					14 0.015		13 0.015				1 0.003		13 0.019	11 0.011	3 0.006	11 0.020	4 0.009	3 0.006							1 0.020	1 0.004
	QCISD(TQ)=FULL					14 0.014		9 0.013				1 0.001		11 0.017	7 0.009	3 0.004	9 0.020	3 0.005	2 0.005							1 0.019	1 0.001
Coupled Cluster	CCD	13 0.379	90 0.158	83 0.160	87 0.165	177 0.101	86 0.144	87 0.144	91 0.138	61 0.168	64 0.163	22 0.012	48 0.070	93 0.139	61 0.060		49 0.072	48 0.067		1 0.013	3 0.024	4 0.030	3 0.037	1 0.019		12 0.013	9 0.015
	CCSD					100 0.049	21 0.008	21 0.008	27 0.004	25 0.247	62 0.058	23 0.008	53 0.067	52 0.070	75 0.054	20 0.008	49 0.073	65 0.007	8 0.008	1 0.011	3 0.012	4 0.005	3 0.009			12 0.011	10 0.005
	CCSD=FULL					78 0.054			2 0.002		62 0.057	20 0.008	53 0.066	53 0.069	77 0.053	16 0.010	48 0.073	64 0.011	8 0.011	1 0.017	3 0.011	4 0.007	3 0.011	1 0.019		10 0.011	9 0.010
	CCSD(T)		3 0.022			85 0.054	39 0.078	23 0.102	34 0.082	26 0.094	18 0.109	19 0.005	48 0.071	54 0.071	62 0.060	20 0.005	49 0.076	40 0.007	15 0.005	2 0.006	5 0.017	6 0.003	1 0.000	1 0.006		8 0.019	8 0.005
	CCSD(T)=FULL					52 0.068			1 0.010			17 0.005	46 0.073	47 0.076	46 0.007	17 0.005	44 0.079	38 0.006	12 0.005		5 0.016	7 0.001	1 0.002	1 0.009		8 0.018	8 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)	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	cc-pCVQZ	aug-cc-pCVTZ	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	147 0.121	146 0.109	149 0.120	147 0.109	149 0.119	148 0.119	2 0.032		146 0.048
	ROHF									3 0.032
density functional	LSDA							2 0.001		3 0.010
	BLYP							2 0.008		25 0.010
	B1B95	86 0.024	68 0.015	2 0.001	2 0.007	2 0.002	2 0.002	2 0.008		25 0.013
	B3LYP	148 0.131	146 0.116	149 0.129	147 0.115	148 0.126	145 0.128	2 0.006		142 0.045
	B3LYPultrafine							2 0.006		25 0.009
	B3PW91							2 0.005		25 0.010
	mPW1PW91							2 0.007		25 0.012
	M06-2X							2 0.011		25 0.012
	PBEPBE							2 0.009		142 0.046
	PBEPBEultrafine							2 0.009		25 0.009
	PBE1PBE							2 0.006		25 0.011
	HSEh1PBE							2 0.006		25 0.012
	TPSSh							2 0.001		25 0.008
	wB97X-D	38 0.097	36 0.083	38 0.096	36 0.082	39 0.089	38 0.089	2 0.009		25 0.012
	B97D3							2 0.006		25 0.008
Moller Plesset perturbation	MP2	150 0.142	146 0.118	152 0.136	146 0.116	152 0.135	152 0.135	2 0.017		141 0.045
	MP2=FULL							2 0.013		24 0.014
	ROMP2									1 0.015
	MP3							2 0.009		20 0.014
	MP3=FULL							2 0.012		20 0.015
	MP4							2 0.018		7 0.012
	MP4=FULL							2 0.014		15 0.010
	B2PLYP							2 0.003		25 0.007
	B2PLYP=FULL							2 0.002		25 0.007
	B2PLYP=FULLultrafine							2 0.002		25 0.007
Configuration interaction	CID							2 0.015		23 0.020
	CISD							2 0.014		23 0.018
Quadratic configuration interaction	QCISD							2 0.001		23 0.007
	QCISD(T)							2 0.008		18 0.005
	QCISD(T)=FULL							2 0.004		19 0.004
	QCISD(TQ)									2 0.004
	QCISD(TQ)=FULL									1 0.001
Coupled Cluster	CCD							2 0.004		22 0.012
	CCSD							2 0.002		21 0.008
	CCSD=FULL							2 0.005		22 0.009
	CCSD(T)							2 0.007		20 0.005
	CCSD(T)=FULL							2 0.003		19 0.003

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.