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.8.

Average Bond Length Differences by Model Chemistry

Calculated at wB97X-D/CEP-31G*

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.103	-0.427	5	13
HeH+	Helium hydride cation	rHHe	0.790		0.585	-0.205	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.010	-0.067	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.437	-0.030	1	2
F2	Fluorine diatomic	rFF	1.412		1.389	-0.023	1	2
C2H2O2	Ethanedial	rCH	1.132		1.113	-0.019	1	3
C5H6	Propellane	rCC	1.596	±0.005	1.579	-0.017	2	5
CH3CH2CH2CH3	Butane	rCH	1.117		1.104	-0.013	1	5
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.317	-0.012	1	4
LiOH	lithium hydroxide	rOH	0.969		0.958	-0.011	1	3
HNO3	Nitric acid	rNO	1.406		1.397	-0.009	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.097	-0.008	1	7
FO	Oxygen monofluoride	rFO	1.354		1.349	-0.006	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.317	-0.004	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.011	-0.003	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.100	-0.003	1	6
B2H6	Diborane	rBH	1.200		1.198	-0.002	1	5
C8H8	cubane	rCH	1.097		1.097	0.000	1	9
CH3CH2CHO	Propanal	rCH	1.105		1.105	0.000	2	8
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.974	0.001	1	2
CH2NH	Methanimine	rCH	1.103		1.105	0.002	1	3
NH4+	ammonium cation	rHN	1.029	±0.000	1.031	0.002	1	2
C5H6	Propellane	rCC	1.525	±0.002	1.528	0.003	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.021	0.003	2	6
HS+	sulfur monohydride cation	rSH	1.374		1.378	0.003	1	2
CH3CH2OH	Ethanol	rCH	1.098		1.101	0.003	1	6
CH3CH2CHO	Propanal	rCH	1.115		1.118	0.003	3	10
CH3CHO	Acetaldehyde	rCH	1.114		1.118	0.004	1	4
CH3CCH	propyne	rCH	1.096		1.100	0.004	1	5
CH3CH2CHO	Propanal	rCH	1.096		1.101	0.005	1	5
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.417	0.006	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.097	0.006	2	5
CH3CHS	Thioacetaldehyde	rCH	1.098		1.105	0.007	2	6
CH3NH2	methyl amine	rCN	1.471	±0.003	1.478	0.007	1	2
CH3NO	nitrosomethane	rCH	1.094		1.101	0.007	1	4
C3H8	Propane	rCH	1.096		1.103	0.007	1	4
CH2CO	Ketene	rCH	1.083		1.090	0.007	1	4
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.504	0.007	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.100	0.007	4	8
CH3CHS	Thioacetaldehyde	rCH	1.090		1.098	0.008	2	5
PN	Phosphorus mononitride	rP#N	1.491		1.499	0.008	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.102	0.008	4	10
C4H8	cyclobutane	rCH	1.093		1.101	0.008	1	5
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.099	0.008	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.093	0.008	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.489	0.009	1	2
C4H8	cyclobutane	rCH	1.091		1.100	0.009	1	6
C4H8O2	Ethyl acetate	rCO	1.345		1.354	0.009	2	3
C3H6	Cyclopropane	rCH	1.083		1.093	0.010	1	4
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.109	0.010	2	6
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.102	0.010	1	3
CH3NO	nitrosomethane	rCH	1.092		1.102	0.010	1	5
H2O	Water	rOH	0.958	±0.000	0.968	0.010	1	2
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.092	0.010	2	5
CH2CHF	Ethene, fluoro-	rCH	1.082		1.092	0.010	1	4
C2H2	Acetylene	rCH	1.063		1.074	0.011	1	3
CH3CHS	Thioacetaldehyde	rCH	1.089		1.100	0.011	1	4
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.928	0.011	1	2
B2H6	Diborane	rBH	1.320		1.331	0.011	1	3
CH3CCH	propyne	rCH	1.060		1.071	0.011	3	4
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.104	0.012	3	6
OH	Hydroxyl radical	rOH	0.970		0.981	0.012	1	2
C3H4	cyclopropene	rCH	1.088		1.100	0.012	1	6
CH2CHCH2CH3	1-Butene	rCC	1.536		1.548	0.012	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.710	0.012	1	3
CH3CH2CH2CH3	Butane	rCC	1.531		1.544	0.013	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.099	0.013	2	5
HCl+	hydrogen chloride cation	rHCl	1.315		1.328	0.013	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.099	0.014	2	4
BO	boron monoxide	rB=O	1.205		1.218	0.014	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.091	0.014	1	3
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.129	0.014	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.524	0.014	1	2
CH4	Methane	rCH	1.087	±0.001	1.101	0.014	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.358	0.014	2	3
CH3CH2OH	Ethanol	rCH	1.088		1.103	0.015	1	5
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.103	0.015	4	6
CN	Cyano radical	rC#N	1.172		1.187	0.015	1	2
CH2CHF	Ethene, fluoro-	rCH	1.077		1.092	0.015	2	5
CH3CH2CHO	Propanal	rCC	1.523		1.538	0.015	1	2
C3H4	cyclopropene	rCH	1.072		1.087	0.015	2	4
OH-	hydroxide anion	rOH	0.964		0.979	0.015	1	2
CH2CO	Ketene	rC=O	1.162		1.177	0.015	2	3
CH	Methylidyne	rCH	1.120		1.135	0.015	1	2
CF	Fluoromethylidyne	rCF	1.276		1.292	0.016	1	2
O2	Oxygen diatomic	rO=O	1.208		1.223	0.016	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.367	0.016	1	4
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.100	0.016	1	2
C2H3	vinyl	rCH	1.085		1.102	0.017	2	4
C4H8O2	Ethyl acetate	rCC	1.515		1.532	0.017	5	6
C4H8O2	Ethyl acetate	rC=O	1.203		1.220	0.017	2	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.345	0.017	1	3
CH3CH2CHO	Propanal	rCC	1.509		1.526	0.017	2	3
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.514	0.017	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.242	0.017	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.441	0.017	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.110	0.017	1	3
BF	Boron monofluoride	rBF	1.267	±0.000	1.284	0.018	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.292	0.018	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.172	0.018	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.614	0.018	1	2
C4H8O2	Ethyl acetate	rCC	1.508		1.526	0.018	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.544	0.019	1	3
SiH3Cl	chlorosilane	rSiH	1.475		1.494	0.019	1	3
SiH4	Silane	rSiH	1.480	±0.000	1.499	0.020	1	2
N3	azide radical	rNN	1.181		1.201	0.020	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.496	0.020	1	3
CO	Carbon monoxide	rC#O	1.128	±0.000	1.149	0.021	1	2
CH3CH2OH	Ethanol	rCH	1.086		1.107	0.021	2	8
BH	Boron monohydride	rBH	1.232		1.254	0.021	1	2
NO+	nitric oxide cation	rN=O	1.066		1.087	0.022	1	2
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.202	0.022	1	3
H2CS	Thioformaldehyde	rC=S	1.611		1.633	0.022	1	2
C2H2O2	Ethanedial	rCC	1.526		1.549	0.023	1	2
HS-	mercapto anion	rSH	1.343		1.367	0.024	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.484	0.024	1	2
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.698	0.025	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.653	0.025	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.518	0.025	2	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.487	0.025	1	2
C3H6	Cyclopropane	rCC	1.501		1.527	0.026	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.793	0.026	1	4
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.956	0.027	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.674	0.027	1	2
C10H8	naphthalene	rC:C	1.410		1.437	0.027	2	3
PH	phosphorus monohydride	rPH	1.422		1.449	0.027	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.626	0.027	1	2
PS	phosphorus sulfide	rP=S	1.900		1.927	0.027	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.356	0.027	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.489	0.028	1	4
C3O2	Carbon suboxide	rC=O	1.146		1.174	0.028	2	4
SSO	Disulfur monoxide	rS=O	1.456		1.485	0.028	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.505	0.029	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.282	0.029	1	2
SiH	Silylidyne	rSiH	1.520		1.550	0.029	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.127	0.030	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.922	0.030	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.288	0.030	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.625	0.031	1	2
SO	Sulfur monoxide	rS=O	1.481		1.513	0.032	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.887	0.032	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.537	0.032	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.688	0.034	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.747	0.034	1	4
S2	Sulfur diatomic	rS=S	1.889		1.924	0.035	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.919	0.035	2	3
SiF	silicon monofluoride	rSiF	1.604		1.641	0.037	1	2
C2H2	Acetylene	rC#C	1.203		1.239	0.037	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.683	0.037	1	2
MgH	magnesium monohydride	rMgH	1.730		1.767	0.037	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.814	0.037	1	4
SiH3Cl	chlorosilane	rSiCl	2.051		2.088	0.038	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.634	0.038	1	3
PF5	Phosphorus pentafluoride	rFP	1.577		1.615	0.038	1	5
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.629	0.038	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.073	0.040	1	4
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.104	0.043	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.474	0.043	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.589	0.044	1	4
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.111	0.044	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.579	0.045	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.657	0.047	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.626	0.047	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.588	0.049	1	5
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.109	0.050	1	3
LiNH2	lithium amide	rLiN	1.736	±0.003	1.790	0.054	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.308	0.057	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.772	0.058	1	3
LiOH	lithium hydroxide	rLiO	1.582		1.640	0.058	1	2
NaLi	lithium sodium	rLiNa	2.889		2.951	0.062	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.670	0.067	1	3
C4H8O2	Ethyl acetate	rCO	1.448		1.532	0.084	5	6
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.107	0.087	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.676	0.112	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.415	0.316	1	2

175 molecules.