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)=FULL/cc-pVTZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
CaO	Calcium monoxide	rOCa	1.822		1.672	-0.150	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.236	-0.029	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.091	-0.026	1	5
LiOH	lithium hydroxide	rOH	0.969		0.948	-0.022	1	3
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.516	-0.018	1	2
B2H6	Diborane	rBH	1.200		1.182	-0.018	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.458	-0.017	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.513	-0.017	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.451	-0.016	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.336	-0.016	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.087	-0.016	1	6
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.016	1	2
CH2NH	Methanimine	rCH	1.103		1.088	-0.015	1	3
C5H6	Propellane	rCC	1.596	±0.005	1.581	-0.015	2	5
B2H6	Diborane	rBH	1.320		1.306	-0.014	1	3
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.000	-0.014	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.102	-0.013	3	10
CH3CH2CHO	Propanal	rCH	1.105		1.092	-0.013	2	8
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.280	-0.012	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.102	-0.012	1	4
CH2	Methylene	rCH	1.085		1.073	-0.012	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.764	-0.012	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.468	-0.012	1	2
C5H6	Propellane	rCC	1.525	±0.002	1.514	-0.011	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.487	-0.010	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.080	-0.010	1	3
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.964	-0.010	1	2
CH2CO	Ketene	rCH	1.083		1.073	-0.009	1	4
HS+	sulfur monohydride cation	rSH	1.374		1.365	-0.009	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.522	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.087	-0.009	1	5
CH2CHCH2CH3	1-Butene	rCC	1.536		1.527	-0.009	1	2
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.082	-0.009	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.933	-0.009	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.413	-0.008	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.463	-0.008	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.502	-0.008	1	2
CH3CCH	propyne	rCH	1.096		1.088	-0.008	1	5
NH4+	ammonium cation	rHN	1.029	±0.000	1.020	-0.008	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.728	-0.008	1	2
CH3OC2H5	Ethane, methoxy-	rCO	1.415	±0.005	1.407	-0.008	1	2
CH3NO	nitrosomethane	rCH	1.094		1.086	-0.008	1	4
GeH	germylidene	rGeH	1.588		1.581	-0.007	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.441	-0.007	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.453	-0.007	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.011	-0.007	2	6
CH3CH2CHO	Propanal	rCC	1.509		1.502	-0.007	2	3
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.075	-0.007	2	5
C2H	Ethynyl radical	rC#C	1.217		1.210	-0.007	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.087	-0.006	4	8
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.079	-0.006	1	2
CH	Methylidyne	rCH	1.120		1.114	-0.006	1	2
BH	Boron monohydride	rBH	1.232		1.226	-0.006	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.088	-0.006	4	10
CH3CH2CHO	Propanal	rCC	1.523		1.517	-0.006	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.076	-0.006	1	4
As4	Arsenic tetramer	rAsAs	2.435		2.429	-0.006	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.409	-0.005	1	2
C4H8	cyclobutane	rCH	1.091		1.086	-0.005	1	6
C4H8	cyclobutane	rCH	1.093		1.088	-0.005	1	5
CH3OC2H5	Ethane, methoxy-	rCH	1.092	±0.007	1.087	-0.005	4	11
CH3OC2H5	Ethane, methoxy-	rCH	1.099	±0.007	1.094	-0.005	1	6
CH3OC2H5	Ethane, methoxy-	rCH	1.100	±0.003	1.095	-0.005	3	8
C3H4	cyclopropene	rCH	1.088		1.084	-0.004	1	6
CH3NO	nitrosomethane	rCH	1.092		1.088	-0.004	1	5
BeH	beryllium monohydride	rBeH	1.343		1.339	-0.004	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.521	-0.004	1	3
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.340	-0.004	2	3
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.089	-0.003	1	3
CH3CCH	propyne	rCH	1.060		1.058	-0.002	3	4
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.729	-0.002	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.075	-0.002	1	3
LiOH	lithium hydroxide	rLiO	1.582		1.579	-0.002	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.772	-0.002	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.474	-0.002	1	3
C3H4	cyclopropene	rCH	1.072		1.070	-0.002	2	4
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.251	-0.002	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.157	-0.002	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.085	-0.001	2	5
SiH4	Silane	rSiH	1.480	±0.000	1.479	-0.001	1	2
CF	Fluoromethylidyne	rCF	1.276		1.275	-0.001	1	2
CH4	Methane	rCH	1.087	±0.001	1.086	-0.001	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.080	-0.001	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.474	-0.001	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.076	-0.001	2	5
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.595	-0.001	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.082	-0.001	1	3
N3	azide radical	rNN	1.181		1.180	-0.001	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.089	±0.008	1.088	-0.001	4	10
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.916	-0.001	1	2
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.672	-0.001	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.970	-0.001	1	3
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.925	0.000	1	4
CH3OC2H5	Ethane, methoxy-	rCH	1.086	±0.010	1.086	0.000	1	5
GeF	Germanium monofluoride	rFGe	1.745		1.745	0.000	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.736	0.000	1	2
H2O	Water	rOH	0.958	±0.000	0.958	0.000	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.753	0.000	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.088	0.000	4	6
CH3NH2	methyl amine	rCH	1.093	±0.000	1.093	0.000	1	3
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.181	0.001	1	3
HCl+	hydrogen chloride cation	rHCl	1.315		1.315	0.001	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.275	0.001	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.596	0.001	1	2
H2	Hydrogen diatomic	rHH	0.741		0.743	0.001	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.516	0.001	1	3
HS	Mercapto radical	rSH	1.341		1.342	0.001	1	2
C2H3	vinyl	rCH	1.085		1.086	0.001	2	4
NO+	nitric oxide cation	rN=O	1.066		1.067	0.001	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.085	0.001	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.779	0.002	1	4
NO	Nitric oxide	rN=O	1.154	±0.000	1.155	0.002	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.352	0.002	1	4
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.226	0.002	1	2
F2	Fluorine diatomic	rFF	1.412		1.414	0.002	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.936	0.002	1	2
OH-	hydroxide anion	rOH	0.964		0.966	0.002	1	2
O2	Oxygen diatomic	rO=O	1.208		1.210	0.002	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.159	0.002	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.712	0.003	1	3
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.695	0.003	1	2
HS-	mercapto anion	rSH	1.343		1.346	0.003	1	2
PH	phosphorus monohydride	rPH	1.422		1.425	0.003	1	2
CH2CO	Ketene	rC=O	1.162		1.165	0.003	2	3
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.331	0.003	1	3
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.643	0.003	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.610	0.003	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.180	0.003	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.698	0.003	1	3
CH2CHCH2CH3	1-Butene	rCC	1.493		1.496	0.003	2	3
N2	Nitrogen diatomic	rN#N	1.098		1.101	0.003	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.167	0.004	1	2
MgH	magnesium monohydride	rMgH	1.730		1.733	0.004	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.335	0.004	1	2
FO	Oxygen monofluoride	rFO	1.354		1.358	0.004	1	2
CH3OC2H5	Ethane, methoxy-	rCO	1.407	±0.004	1.411	0.004	2	3
SiH+	silicon monohydride cation	rSiH	1.504		1.509	0.004	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.466	0.005	1	4
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.465	0.005	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.764	0.005	1	2
LiO	lithium oxide	rLiO	1.688		1.693	0.005	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.175	0.005	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.134	0.005	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.558	0.005	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.772	0.005	1	4
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.860	0.006	1	2
C2	Carbon diatomic	rC=C	1.243		1.248	0.006	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.083	0.006	1	2
SiH	Silylidyne	rSiH	1.520		1.526	0.006	1	2
BO	boron monoxide	rB=O	1.205		1.211	0.006	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.672	0.007	1	2
NaLi	lithium sodium	rLiNa	2.889		2.896	0.007	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.028	0.007	1	2
BN	boron nitride	rB=N	1.325		1.332	0.007	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.604	0.008	1	3
H2CS	Thioformaldehyde	rC=S	1.611		1.619	0.008	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.721	0.008	1	4
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.706	0.008	1	3
NSe	Nitrogen monoselenide	rN=Se	1.652		1.661	0.009	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.176	0.010	1	2
BrO	Bromine monoxide	rOBr	1.718		1.728	0.011	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.605	0.011	1	2
GeO	Germanium monoxide	rOGe	1.625		1.636	0.011	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.687	0.011	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.590	0.011	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.611	0.012	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.062	0.012	1	2
C2H	Ethynyl radical	rCH	1.047		1.058	0.012	1	3
LiF	lithium fluoride	rLiF	1.564	±0.000	1.576	0.012	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.552	0.013	1	5
PN	Phosphorus mononitride	rP#N	1.491		1.504	0.014	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.026	0.014	1	2
SiF	silicon monofluoride	rSiF	1.604		1.619	0.014	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.970	0.015	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.048	0.015	1	4
Br2	Bromine diatomic	rBrBr	2.281		2.296	0.015	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.512	0.015	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.078	0.016	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.607	0.016	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.527	0.017	1	2
SO	Sulfur monoxide	rS=O	1.481		1.499	0.018	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.164	0.018	2	4
PO	Phosphorus monoxide	rP=O	1.476		1.494	0.018	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.154	0.018	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.945	0.019	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.086	0.019	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.476	0.019	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.451	0.020	1	2
PS	phosphorus sulfide	rP=S	1.900		1.921	0.021	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.676	0.022	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.951	0.022	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.273	0.022	1	2
S2	Sulfur diatomic	rS=S	1.889		1.913	0.024	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.628	0.025	1	3
Cl2	Chlorine diatomic	rClCl	1.988		2.013	0.025	1	2
SCl	sulfur monochloride	rSCl	1.975		2.002	0.026	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.914	0.030	2	3
CFCl	chlorofluoromethylene	rCCl	1.714		1.751	0.037	1	3
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.398	0.037	1	2

200 molecules.