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

---

NIST policy on privacy, security, and accessibility.

---

© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

IV.D.8.

Average Bond Length Differences by Model Chemistry

Calculated at B2PLYP=FULLultrafine/6-31G**

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.092	-0.438	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.995	-0.083	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.623	-0.029	1	2
C2H2O2	Ethanedial	rCH	1.132		1.104	-0.028	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.095	-0.022	1	5
C4H8O2	Ethyl acetate	rCH	1.105		1.086	-0.019	1	7
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.518	-0.017	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.459	-0.016	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.016	1	2
LiOH	lithium hydroxide	rOH	0.969		0.953	-0.016	1	3
B2H6	Diborane	rBH	1.200		1.185	-0.015	1	5
CH3CH2CHO	Propanal	rCH	1.103		1.090	-0.013	1	6
HS+	sulfur monohydride cation	rSH	1.374		1.362	-0.012	1	2
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.317	-0.012	1	4
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.469	-0.011	1	2
C5H6	Propellane	rCC	1.596	±0.005	1.585	-0.011	2	5
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.282	-0.010	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.520	-0.010	1	2
CH2NH	Methanimine	rCH	1.103		1.094	-0.009	1	3
B2H6	Diborane	rBH	1.320		1.311	-0.009	1	3
C5H6	Propellane	rCC	1.525	±0.002	1.516	-0.009	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.462	-0.009	1	2
C8H8	cubane	rCH	1.097		1.088	-0.009	1	9
LiF	lithium fluoride	rLiF	1.564	±0.000	1.555	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.097	-0.008	2	8
C2H2O2	Ethanedial	rCC	1.526		1.518	-0.008	1	2
CH2	Methylene	rCH	1.085		1.077	-0.008	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.783	-0.007	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.454	-0.006	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.090	-0.006	1	5
C2H	Ethynyl radical	rC#C	1.217		1.211	-0.006	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.109	-0.006	3	10
H2CSe	Selenoformaldehyde	rHC	1.090		1.085	-0.005	1	3
CH3CHO	Acetaldehyde	rCH	1.114		1.109	-0.005	1	4
CH3CCH	propyne	rCH	1.096		1.091	-0.005	1	5
NH4+	ammonium cation	rHN	1.029	±0.000	1.024	-0.005	1	2
CH2CO	Ketene	rCH	1.083		1.078	-0.004	1	4
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.493	-0.004	1	2
CH3NO	nitrosomethane	rCH	1.094		1.090	-0.004	1	4
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.521	-0.004	1	3
HBr+	hydrogen bromide cation	rHBr	1.448		1.444	-0.004	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.014	-0.004	2	6
CH3CHS	Thioacetaldehyde	rCH	1.098		1.094	-0.004	2	6
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.750	-0.003	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.411	-0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.090	-0.003	4	8
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.970	-0.003	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.012	-0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.091	-0.003	4	10
CH2CHCH2CH3	1-Butene	rCC	1.536		1.533	-0.003	1	2
H2	Hydrogen diatomic	rHH	0.741		0.739	-0.003	1	2
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.080	-0.002	2	5
C4H8O2	Ethyl acetate	rCC	1.515		1.513	-0.002	5	6
CH3CHS	Thioacetaldehyde	rCH	1.090		1.088	-0.002	2	5
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.089	-0.002	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.707	-0.002	1	3
C3H8	Propane	rCH	1.096		1.094	-0.002	1	4
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.342	-0.002	2	3
CH3CH2CH2CH3	Butane	rCC	1.531		1.529	-0.002	1	2
F2	Fluorine diatomic	rFF	1.412		1.410	-0.002	1	2
C4H8	cyclobutane	rCH	1.093		1.092	-0.002	1	5
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.263	-0.001	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.090	-0.001	2	5
CH3CH2CHO	Propanal	rCC	1.509		1.508	-0.001	2	3
C4H8O2	Ethyl acetate	rCC	1.508		1.507	-0.001	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.510	-0.001	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.479	-0.001	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.098	-0.001	2	6
SiH3Cl	chlorosilane	rSiH	1.475		1.474	-0.001	1	3
C3H6	Cyclopropane	rCH	1.083		1.082	-0.001	1	4
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.084	-0.001	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.522	-0.001	1	2
CH3NO	nitrosomethane	rCH	1.092		1.092	0.000	1	5
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.411	0.000	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.467	0.000	1	2
C4H8	cyclobutane	rCH	1.091		1.091	0.000	1	6
HCl+	hydrogen chloride cation	rHCl	1.315		1.315	0.000	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.421	0.000	1	2
GeH	germylidene	rGeH	1.588		1.588	0.000	1	2
C2H2	Acetylene	rCH	1.063		1.063	0.000	1	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.082	0.000	1	4
SiH3F	monofluorosilane	rSiH	1.476		1.477	0.001	1	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.093	0.001	3	6
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.696	0.001	1	3
CH4	Methane	rCH	1.087	±0.001	1.088	0.001	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.436	0.001	1	2
C3H4	cyclopropene	rCH	1.088		1.090	0.002	1	6
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.255	0.002	1	2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.657	0.002	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.088	0.002	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.084	0.002	1	3
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.331	0.002	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.092	0.003	1	4
CH3CCH	propyne	rCH	1.060		1.063	0.003	3	4
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.173	0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.095	0.003	1	3
FO	Oxygen monofluoride	rFO	1.354		1.357	0.003	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.080	0.003	1	3
BH	Boron monohydride	rBH	1.232		1.236	0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.091	0.003	4	6
CH2CHF	Ethene, fluoro-	rCH	1.077		1.080	0.003	2	5
C3H4	cyclopropene	rCH	1.072		1.075	0.003	2	4
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.278	0.004	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.089	0.004	2	4
C3H6	Cyclopropane	rCC	1.501		1.505	0.004	1	2
PH	phosphorus monohydride	rPH	1.422		1.426	0.004	1	2
HNO3	Nitric acid	rNO	1.406		1.410	0.004	1	2
H2O	Water	rOH	0.958	±0.000	0.962	0.004	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.586	0.005	1	2
CH	Methylidyne	rCH	1.120		1.125	0.005	1	2
OH	Hydroxyl radical	rOH	0.970		0.975	0.005	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.509	0.005	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.922	0.006	1	2
C2H3	vinyl	rCH	1.085		1.091	0.006	2	4
C10H8	naphthalene	rC:C	1.410		1.416	0.006	2	3
HS-	mercapto anion	rSH	1.343		1.349	0.006	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.742	0.006	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.099	0.006	1	3
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.231	0.007	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.618	0.007	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.949	0.007	1	2
SiH	Silylidyne	rSiH	1.520		1.527	0.007	1	2
N3	azide radical	rNN	1.181		1.188	0.007	1	2
C2H2	Acetylene	rC#C	1.203		1.210	0.007	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.091	0.007	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.782	0.007	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.505	0.008	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.470	0.008	1	4
CH2CHCH2CH3	1-Butene	rCC	1.493		1.501	0.008	2	3
C4H8O2	Ethyl acetate	rCO	1.345		1.354	0.009	2	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.562	0.009	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.361	0.010	1	4
BO	boron monoxide	rB=O	1.205		1.214	0.010	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.169	0.010	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.525	0.011	1	3
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.687	0.011	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.658	0.011	1	2
C4H8O2	Ethyl acetate	rC=O	1.203		1.214	0.011	2	4
CN	Cyano radical	rC#N	1.172		1.183	0.011	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.364	0.012	1	2
CF	Fluoromethylidyne	rCF	1.276		1.288	0.012	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.307	0.012	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.341	0.012	1	3
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.780	0.013	1	4
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.667	0.013	1	2
CH2CO	Ketene	rC=O	1.162		1.175	0.013	2	3
MgH	magnesium monohydride	rMgH	1.730		1.743	0.013	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.128	0.013	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.167	0.013	1	2
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.194	0.014	1	3
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.286	0.014	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.143	0.015	1	2
OH-	hydroxide anion	rOH	0.964		0.979	0.015	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.114	0.016	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.594	0.017	1	5
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.613	0.017	1	2
C2H	Ethynyl radical	rCH	1.047		1.064	0.017	1	3
SiH3F	monofluorosilane	rSiF	1.595		1.612	0.018	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.872	0.018	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.943	0.018	1	4
NO+	nitric oxide cation	rN=O	1.066		1.084	0.018	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.068	0.018	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.031	0.018	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.764	0.019	1	2
O2	Oxygen diatomic	rO=O	1.208		1.226	0.019	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.797	0.020	1	4
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.751	0.020	1	2
NaLi	lithium sodium	rLiNa	2.889		2.909	0.020	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.511	0.020	1	2
SiF	silicon monofluoride	rSiF	1.604		1.625	0.020	1	2
PS	phosphorus sulfide	rP=S	1.900		1.921	0.021	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.955	0.021	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.667	0.021	1	2
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.694	0.021	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.054	0.021	1	4
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.951	0.021	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.118	0.022	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.533	0.023	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.721	0.024	1	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.486	0.024	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.614	0.024	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.738	0.025	1	4
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.284	0.026	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.192	0.026	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.785	0.026	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.183	0.026	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.278	0.027	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.607	0.028	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.627	0.028	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.624	0.028	1	3
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.090	0.028	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.453	0.029	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.096	0.029	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.176	0.030	2	4
PO	Phosphorus monoxide	rP=O	1.476		1.507	0.031	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.566	0.032	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.113	0.032	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.661	0.032	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.314	0.033	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.641	0.034	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.673	0.034	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.699	0.034	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.055	0.035	1	2
BrO	Bromine monoxide	rOBr	1.718		1.753	0.036	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.199	0.036	1	2
S2	Sulfur diatomic	rS=S	1.889		1.925	0.036	1	2
GeO	Germanium monoxide	rOGe	1.625		1.661	0.036	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.096	0.037	1	3
SCl	sulfur monochloride	rSCl	1.975		2.013	0.038	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.649	0.038	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.174	0.038	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.470	0.039	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.497	0.041	1	2
SO	Sulfur monoxide	rS=O	1.481		1.522	0.041	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.926	0.042	2	3
KH	Potassium hydride	rKH	2.243	±0.001	2.285	0.042	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.934	0.042	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.588	0.043	1	4
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.590	0.051	1	5
CFCl	chlorofluoromethylene	rCCl	1.714		1.772	0.058	1	3
C4H8O2	Ethyl acetate	rCO	1.448		1.513	0.065	5	6
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.674	0.071	1	3
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.699	0.105	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.416	0.115	1	2
CaO	Calcium monoxide	rOCa	1.822		2.048	0.226	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.411	0.312	1	2

227 molecules.