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 QCISD(T)/aug-cc-pVTZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C2H2O2	Ethanedial	rCH	1.132		1.104	-0.028	1	3
LiOH	lithium hydroxide	rOH	0.969		0.952	-0.017	1	3
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.522	-0.013	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.308	-0.013	1	2
B2H6	Diborane	rBH	1.200		1.189	-0.011	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.464	-0.011	1	2
CH2NH	Methanimine	rCH	1.103		1.093	-0.010	1	3
HF+	hydrogen fluoride cation	rHF	1.014		1.004	-0.010	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.282	-0.010	1	2
HCCl	Chloromethylene	rCH	1.119	±0.036	1.111	-0.008	1	3
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.472	-0.008	1	2
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.084	-0.006	1	3
CH3CHO	Acetaldehyde	rCH	1.114		1.108	-0.006	1	4
CH2	Methylene	rCH	1.085		1.079	-0.006	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.967	-0.006	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.416	-0.005	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.024	-0.005	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.369	-0.005	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.086	-0.005	1	3
B2H6	Diborane	rBH	1.320		1.315	-0.005	1	3
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.086	-0.004	1	4
CH3CCH	propyne	rCH	1.096		1.092	-0.004	1	5
C2H2O2	Ethanedial	rCC	1.526		1.522	-0.004	1	2
CH2CO	Ketene	rCH	1.083		1.079	-0.004	1	4
CH3NH2	methyl amine	rNH	1.018	±0.001	1.014	-0.004	2	6
HBr+	hydrogen bromide cation	rHBr	1.448		1.445	-0.003	1	2
GeH	germylidene	rGeH	1.588		1.585	-0.003	1	2
CH3NO	nitrosomethane	rCH	1.094		1.091	-0.003	1	4
C5H6	Propellane	rCC	1.525	±0.002	1.522	-0.003	1	2
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.089	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.091	-0.002	4	8
AsH3	Arsine	rAsH	1.511	±0.000	1.509	-0.001	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.093	-0.001	4	10
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.081	-0.001	2	5
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.413	-0.001	1	2
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
H2Se	Hydrogen selenide	rSeH	1.460		1.459	-0.001	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.470	-0.001	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.524	-0.001	1	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.090	-0.001	2	5
C4H8	cyclobutane	rCH	1.093		1.093	0.000	1	5
C5H6	Propellane	rCC	1.596	±0.005	1.596	0.000	2	5
HOBr	Hypobromous acid	rBrO	1.834		1.834	0.000	2	3
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.673	0.000	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.596	0.000	1	2
C4H8	cyclobutane	rCH	1.091		1.091	0.000	1	6
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.344	0.000	2	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.082	0.000	1	4
C3H4	cyclopropene	rCH	1.088		1.088	0.000	1	6
CH3NO	nitrosomethane	rCH	1.092		1.092	0.000	1	5
C2H2	Acetylene	rCH	1.063		1.064	0.001	1	3
NH2F	monofluoroamine	rNF	1.433		1.434	0.001	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.082	0.001	1	2
BH3	boron trihydride	rBH	1.190		1.191	0.001	1	2
H2	Hydrogen diatomic	rHH	0.741		0.743	0.002	1	2
CH	Methylidyne	rCH	1.120		1.122	0.002	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.255	0.002	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.478	0.002	1	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.094	0.002	3	6
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.095	0.003	1	3
OCSe	Carbonyl selenide	rC=O	1.159		1.161	0.003	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.079	0.003	1	3
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.470	0.003	1	2
CH4	Methane	rCH	1.087	±0.001	1.090	0.003	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.478	0.003	1	3
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.928	0.003	1	4
BH	Boron monohydride	rBH	1.232		1.235	0.003	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.089	0.003	2	5
SiH4	Silane	rSiH	1.480	±0.000	1.483	0.003	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.086	0.003	1	3
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.518	0.004	1	3
HO2	Hydroperoxy radical	rOH	0.971		0.974	0.004	1	3
CH3CCH	propyne	rCH	1.060		1.064	0.004	3	4
HCl+	hydrogen chloride cation	rHCl	1.315		1.318	0.004	1	2
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.184	0.004	1	3
H2O	Water	rOH	0.958	±0.000	0.962	0.004	1	2
N3	azide radical	rNN	1.181		1.185	0.004	1	2
C3H4	cyclopropene	rCH	1.072		1.076	0.004	2	4
NO+	nitric oxide cation	rN=O	1.066		1.070	0.004	1	2
OH	Hydroxyl radical	rOH	0.970		0.974	0.004	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.921	0.004	1	2
OH-	hydroxide anion	rOH	0.964		0.968	0.004	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.276	0.004	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.279	0.004	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.097	0.004	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.082	0.005	2	5
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.502	0.005	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.758	0.005	1	2
HS	Mercapto radical	rSH	1.341		1.346	0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.093	0.005	4	6
HNO3	Nitric acid	rNO	1.406		1.412	0.006	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.160	0.006	1	2
HOBr	Hypobromous acid	rOH	0.961		0.967	0.006	1	2
HS-	mercapto anion	rSH	1.343		1.349	0.006	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.940	0.006	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.123	0.006	1	2
BeH	beryllium monohydride	rBeH	1.343		1.349	0.006	1	2
CH2CO	Ketene	rC=O	1.162		1.168	0.006	2	3
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.090	0.006	1	2
CF	Fluoromethylidyne	rCF	1.276		1.283	0.006	1	2
F2	Fluorine diatomic	rFF	1.412		1.418	0.006	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.766	0.007	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.442	0.007	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.231	0.007	1	2
O2	Oxygen diatomic	rO=O	1.208		1.214	0.007	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.104	0.007	1	2
C2H3	vinyl	rCH	1.085		1.092	0.007	2	4
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.333	0.007	1	2
PH	phosphorus monohydride	rPH	1.422		1.429	0.007	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.738	0.007	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.360	0.007	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.647	0.008	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.512	0.008	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.717	0.008	1	3
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.468	0.008	1	2
C2H2	Acetylene	rC#C	1.203		1.211	0.008	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.124	0.009	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.337	0.009	1	3
BF	Boron monofluoride	rBF	1.267	±0.000	1.275	0.009	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.137	0.009	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.186	0.009	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.470	0.009	1	4
SiH	Silylidyne	rSiH	1.520		1.529	0.009	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.316	0.009	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.704	0.009	1	3
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.166	0.009	1	2
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.701	0.009	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.360	0.009	1	4
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.784	0.009	1	2
SiC	silicon monocarbide	rCSi	1.722		1.731	0.009	1	2
BrO	Bromine monoxide	rOBr	1.718		1.727	0.010	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.617	0.010	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.341	0.010	1	2
C3H6	Cyclopropane	rCC	1.501		1.511	0.010	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.755	0.010	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.746	0.010	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.787	0.010	1	4
NH2CONH2	Urea	rNH	0.998		1.009	0.011	4	8
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.778	0.011	1	4
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.564	0.011	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.676	0.011	1	2
FO	Oxygen monofluoride	rFO	1.354		1.365	0.011	1	2
C2	Carbon diatomic	rC=C	1.243		1.254	0.011	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.709	0.012	1	3
HCCl	Chloromethylene	rCCl	1.696	±0.003	1.708	0.012	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.542	0.012	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.664	0.012	1	2
BO	boron monoxide	rB=O	1.205		1.217	0.013	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.624	0.013	1	2
B2	Boron diatomic	rBB	1.590		1.603	0.013	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.091	0.013	1	2
NS+	nitrogen sulfide cation	rNS	1.440		1.454	0.014	1	2
BN	boron nitride	rB=N	1.325		1.340	0.015	1	2
BeO	beryllium oxide	rBe=O	1.331		1.346	0.015	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.181	0.015	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.610	0.015	1	2
MgH	magnesium monohydride	rMgH	1.730		1.745	0.015	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.179	0.015	1	2
GeO	Germanium monoxide	rOGe	1.625		1.640	0.015	1	2
CuH	Copper monohydride	rCuH	1.463		1.478	0.016	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.752	0.016	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.692	0.016	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.663	0.017	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.872	0.017	1	2
C3H5	Allyl radical	rCH	1.069		1.087	0.018	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.563	0.018	1	4
PN	Phosphorus mononitride	rP#N	1.491		1.509	0.018	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.515	0.018	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.598	0.019	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.618	0.019	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.613	0.019	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.647	0.019	1	2
MgH+	magnesium monohydride cation	rMgH	1.652		1.671	0.019	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.601	0.019	1	2
PO-	phosphorus monoxide anion	rOP	1.540		1.560	0.020	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.795	0.020	1	2
F2SO	Thionyl Fluoride	rFS	1.585	±0.000	1.605	0.020	1	3
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.032	0.020	1	2
SiF	silicon monofluoride	rSiF	1.604		1.626	0.021	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.167	0.021	2	4
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.531	0.022	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.073	0.022	1	2
SO	Sulfur monoxide	rS=O	1.481		1.503	0.022	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.303	0.022	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.498	0.023	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.613	0.023	1	2
PF+	phosphorus monofluoride cation	rFP	1.500		1.524	0.023	1	2
P2	Phosphorus diatomic	rP#P	1.893		1.917	0.024	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.057	0.024	1	4
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.160	0.024	1	2
LiO	lithium oxide	rLiO	1.688		1.713	0.024	1	2
S2+	sulfur diatomic cation	rS=S	1.825	±0.010	1.850	0.025	1	2
F2SO	Thionyl Fluoride	rO=S	1.413	±0.000	1.437	0.025	1	2
PS	phosphorus sulfide	rP=S	1.900		1.925	0.025	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.981	0.026	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.681	0.026	1	2
HSSSH	trisulfane	rSS	2.054	±0.000	2.080	0.027	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.483	0.027	1	2
Li2	Lithium diatomic	rLiLi	2.673		2.700	0.027	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.591	0.027	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.197	0.027	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.956	0.027	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.089	0.027	1	2
S2	Sulfur diatomic	rS=S	1.889		1.917	0.027	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.048	0.028	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.279	0.028	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.459	0.028	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.294	0.029	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.042	0.029	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.098	0.031	1	2
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.161	0.031	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.020	0.032	1	2
SCl	sulfur monochloride	rSCl	1.975		2.008	0.032	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.917	0.033	2	3
NaH	sodium hydride	rNaH	1.887	±0.000	1.927	0.041	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.755	0.041	1	3
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.413	0.052	1	2
NaLi	lithium sodium	rLiNa	2.889		2.951	0.062	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.998	0.072	1	2

221 molecules.