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-pVDZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.107	-0.423	5	13
Si2	Silicon diatomic	rSiSi	2.246		2.213	-0.033	1	2
C5H8O	Methyl cyclopropyl ketone	rCH	1.126		1.101	-0.025	3	7
C2H2O2	Ethanedial	rCH	1.132		1.116	-0.016	1	3
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.657	-0.016	1	2
LiOH	lithium hydroxide	rOH	0.969		0.956	-0.013	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.109	-0.008	1	5
HF+	hydrogen fluoride cation	rHF	1.014		1.010	-0.004	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.787	-0.003	1	2
C5H8	Ethenylcyclopropane	rCH	1.099		1.097	-0.002	1	6
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.329	-0.000	1	4
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.321	0.000	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.973	0.000	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.030	0.001	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.104	0.001	1	6
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.481	0.001	1	2
CH2NH	Methanimine	rCH	1.103		1.106	0.003	1	3
B2H6	Diborane	rBH	1.200		1.203	0.003	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.478	0.003	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.296	0.004	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.110	0.005	2	8
CH3NH2	methyl amine	rNH	1.018	±0.001	1.023	0.005	2	6
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.540	0.005	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.121	0.006	3	10
C2H2O2	Ethanedial	rCC	1.526		1.532	0.006	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.120	0.006	1	4
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.428	0.007	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.088	0.007	1	2
C3H6O	2-Propen-1-ol	rCH	1.091	±0.010	1.098	0.007	3	9
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.097	0.007	1	3
C3H6O	2-Propen-1-ol	rCH	1.092	±0.010	1.099	0.007	2	7
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.924	0.007	1	2
C3H6O	2-Propen-1-ol	rCH	1.102	±0.020	1.110	0.008	1	6
CH3CCH	propyne	rCH	1.096		1.104	0.008	1	5
HO2	Hydroperoxy radical	rOH	0.971		0.979	0.008	1	3
CH3CH2CHO	Propanal	rCH	1.096		1.104	0.008	1	5
HCCl	Chloromethylene	rCH	1.119	±0.036	1.127	0.008	1	3
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.098	0.008	1	4
CH2CO	Ketene	rCH	1.083		1.091	0.009	1	4
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.100	0.009	1	2
CH2CHCH2CH3	1-Butene	rCC	1.536		1.545	0.009	1	2
H2O	Water	rOH	0.958	±0.000	0.967	0.009	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.540	0.009	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.099	0.009	1	3
CH3NH2	methyl amine	rCN	1.471	±0.003	1.480	0.009	1	2
CH2	Methylene	rCH	1.085		1.094	0.009	1	2
CH3NO	nitrosomethane	rCH	1.094		1.103	0.009	1	4
HS+	sulfur monohydride cation	rSH	1.374		1.384	0.009	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.458	0.010	1	2
OH	Hydroxyl radical	rOH	0.970		0.980	0.010	1	2
OH-	hydroxide anion	rOH	0.964		0.975	0.011	1	2
B2H6	Diborane	rBH	1.320		1.331	0.011	1	3
CHONH2	formamide	rNH	1.001		1.012	0.011	3	6
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.536	0.011	1	3
SiH3F	monofluorosilane	rSiH	1.476		1.488	0.012	1	3
CH3CH2CHO	Propanal	rCC	1.509		1.521	0.012	2	3
CH3OC2H5	Ethane, methoxy-	rCH	1.099	±0.007	1.111	0.012	1	6
C3H6	Cyclopropane	rCH	1.083		1.095	0.012	1	4
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.094	0.012	2	5
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.103	0.012	2	5
HOBr	Hypobromous acid	rOH	0.961		0.973	0.012	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.427	0.012	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.097	0.012	1	2
C4H8	cyclobutane	rCH	1.093		1.106	0.012	1	5
CH3OC2H5	Ethane, methoxy-	rCH	1.092	±0.007	1.104	0.012	4	11
CH3CH2CHO	Propanal	rCC	1.523		1.535	0.012	1	2
CH3OC2H5	Ethane, methoxy-	rCO	1.415	±0.005	1.427	0.012	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.487	0.013	1	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.095	0.013	1	4
CH3OC2H5	Ethane, methoxy-	rCH	1.100	±0.003	1.113	0.013	3	8
C4H8	cyclobutane	rCH	1.091		1.104	0.013	1	6
CH3NO	nitrosomethane	rCH	1.092		1.105	0.013	1	5
C3H6O	2-Propen-1-ol	rCH	1.096	±0.030	1.109	0.013	1	5
C5H6	Propellane	rCC	1.525	±0.002	1.538	0.013	1	2
CHONH2	formamide	rNH	1.001		1.014	0.013	3	5
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.193	0.013	1	3
SiH4	Silane	rSiH	1.480	±0.000	1.493	0.013	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.357	0.013	2	3
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.340	0.013	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.473	0.013	1	2
C5H8O	Methyl cyclopropyl ketone	rCC	1.510		1.524	0.014	2	3
O2	Oxygen diatomic	rO=O	1.208		1.221	0.014	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.173	0.014	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.131	0.015	1	2
C5H8	Ethenylcyclopropane	rCC	1.475		1.490	0.015	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.107	0.015	3	6
ScH	Scandium monohydride	rScH	1.775	±0.000	1.791	0.015	1	2
C2H2	Acetylene	rCH	1.063		1.079	0.016	1	3
CH4	Methane	rCH	1.087	±0.001	1.103	0.016	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.102	0.016	2	5
GeH	germylidene	rGeH	1.588		1.604	0.016	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.086	±0.010	1.102	0.016	1	5
BH3	boron trihydride	rBH	1.190		1.206	0.016	1	2
BeH	beryllium monohydride	rBeH	1.343		1.359	0.016	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.099	0.017	1	3
CH3OC2H5	Ethane, methoxy-	rCH	1.089	±0.008	1.106	0.017	4	10
AsH3	Arsine	rAsH	1.511	±0.000	1.528	0.017	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.110	0.017	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.094	0.017	2	5
NO+	nitric oxide cation	rN=O	1.066		1.083	0.017	1	2
CH3CCH	propyne	rCH	1.060		1.077	0.017	3	4
C2H2+	acetylene cation	rCH	1.077	±0.005	1.094	0.017	1	3
NO	Nitric oxide	rN=O	1.154	±0.000	1.171	0.017	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.332	0.018	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.479	0.018	1	4
CH2CO	Ketene	rC=O	1.162		1.180	0.018	2	3
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.292	0.018	1	2
HNO3	Nitric acid	rNO	1.406		1.424	0.018	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.102	0.018	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.347	0.018	1	2
C3H6O	2-Propen-1-ol	rCH	1.078	±0.010	1.096	0.018	3	8
C2H	Ethynyl radical	rC#C	1.217		1.235	0.018	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.479	0.019	1	2
C2H3	vinyl	rCH	1.085		1.104	0.019	2	4
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.534	0.019	1	3
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.134	0.019	1	2
NH2F	monofluoroamine	rNF	1.433		1.452	0.019	1	2
NH2CONH2	Urea	rNH	0.998		1.017	0.019	4	8
N3	azide radical	rNN	1.181		1.201	0.020	1	2
HS	Mercapto radical	rSH	1.341		1.361	0.020	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.148	0.020	1	2
CH	Methylidyne	rCH	1.120		1.140	0.020	1	2
H2	Hydrogen diatomic	rHH	0.741		0.762	0.020	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.351	0.020	1	2
HS-	mercapto anion	rSH	1.343		1.364	0.020	1	2
BH	Boron monohydride	rBH	1.232		1.253	0.021	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.274	0.021	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.525	0.021	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.515	0.022	2	3
BO	boron monoxide	rB=O	1.205		1.226	0.022	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.246	0.022	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.776	0.022	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.948	0.023	1	4
SiH	Silylidyne	rSiH	1.520		1.543	0.023	1	2
PH	phosphorus monohydride	rPH	1.422		1.446	0.023	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.121	0.024	1	2
C3H6	Cyclopropane	rCC	1.501		1.526	0.025	1	2
MgH	magnesium monohydride	rMgH	1.730		1.755	0.025	1	2
CH3OC2H5	Ethane, methoxy-	rCO	1.407	±0.004	1.432	0.025	2	3
CN-	cyanide anion	rC#N	1.177	±0.004	1.202	0.025	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.735	0.026	1	3
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.354	0.026	1	3
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.721	0.026	1	3
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.523	0.026	1	2
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.719	0.026	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.961	0.027	1	2
C5H6	Propellane	rCC	1.596	±0.005	1.623	0.027	2	5
BN	boron nitride	rB=N	1.325		1.352	0.027	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.495	0.028	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.795	0.028	1	4
C2H2	Acetylene	rC#C	1.203		1.230	0.028	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.802	0.028	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.379	0.028	1	4
BeO	beryllium oxide	rBe=O	1.331		1.360	0.029	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.583	0.030	1	2
MgH+	magnesium monohydride cation	rMgH	1.652		1.682	0.030	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.625	0.030	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.641	0.030	1	2
C3H5	Allyl radical	rCH	1.069		1.100	0.031	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.338	0.031	1	2
FO	Oxygen monofluoride	rFO	1.354		1.387	0.032	1	2
C2	Carbon diatomic	rC=C	1.243		1.275	0.033	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.179	0.033	2	4
C2H	Ethynyl radical	rCH	1.047		1.079	0.033	1	3
CF	Fluoromethylidyne	rCF	1.276		1.309	0.033	1	2
NS+	nitrogen sulfide cation	rNS	1.440		1.474	0.034	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.811	0.034	1	4
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.710	0.034	1	2
SiC	silicon monocarbide	rCSi	1.722		1.757	0.035	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.307	0.035	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.688	0.036	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.618	0.037	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.768	0.037	1	2
HOBr	Hypobromous acid	rBrO	1.834		1.871	0.037	2	3
F2	Fluorine diatomic	rFF	1.412		1.450	0.038	1	2
C5H8O	Cyclopentanone	rCC	1.504		1.542	0.038	2	3
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.703	0.038	1	2
HCCl	Chloromethylene	rCCl	1.696	±0.003	1.734	0.038	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.529	0.038	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.680	0.041	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.786	0.041	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.800	0.041	1	2
GeO	Germanium monoxide	rOGe	1.625		1.666	0.042	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.208	0.042	1	2
B2	Boron diatomic	rBB	1.590		1.633	0.043	1	2
NaH	sodium hydride	rNaH	1.887	±0.000	1.929	0.043	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.607	0.043	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.651	0.044	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.780	0.044	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.311	0.044	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.296	0.045	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.542	0.045	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.202	0.045	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.310	0.046	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.643	0.047	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.783	0.047	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.482	0.047	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.060	0.048	1	2
LiO	lithium oxide	rLiO	1.688		1.737	0.049	1	2
P2	Phosphorus diatomic	rP#P	1.893		1.942	0.049	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.704	0.050	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.748	0.050	1	3
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.129	0.052	1	2
S2+	sulfur diatomic cation	rS=S	1.825	±0.010	1.878	0.053	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.983	0.054	1	2
PS	phosphorus sulfide	rP=S	1.900		1.954	0.054	1	2
Li2	Lithium diatomic	rLiLi	2.673		2.727	0.054	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.532	0.056	1	2
BrO	Bromine monoxide	rOBr	1.718		1.774	0.056	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.653	0.057	1	3
S2	Sulfur diatomic	rS=S	1.889		1.946	0.057	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.567	0.057	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.771	0.057	1	3
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.090	0.057	1	4
SiH3Cl	chlorosilane	rSiCl	2.051		2.108	0.057	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.686	0.058	1	2
F2SO	Thionyl Fluoride	rO=S	1.413	±0.000	1.471	0.058	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.704	0.058	1	2
SO	Sulfur monoxide	rS=O	1.481		1.541	0.060	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.987	0.061	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.226	0.062	1	2
HSSSH	trisulfane	rSS	2.054	±0.000	2.116	0.062	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.657	0.063	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.918	0.063	1	2
AlC	Aluminum carbide	rC=Al	1.955		2.018	0.063	1	2
PO-	phosphorus monoxide anion	rOP	1.540		1.605	0.065	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.664	0.065	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.611	0.066	1	4
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.418	0.066	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.087	0.067	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.428	0.067	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.606	0.067	1	5
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.657	0.067	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.204	0.068	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.081	0.068	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.952	0.068	2	3
SSO	Disulfur monoxide	rS=O	1.456		1.524	0.068	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.599	0.069	1	2
SiF	silicon monofluoride	rSiF	1.604		1.673	0.069	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.350	0.069	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.500	0.069	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.649	0.070	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.133	0.071	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.785	0.072	1	4
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.242	0.072	1	2
SCl	sulfur monochloride	rSCl	1.975		2.048	0.072	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.139	0.072	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.062	0.075	1	2
PF+	phosphorus monofluoride cation	rFP	1.500		1.575	0.075	1	2
NaLi	lithium sodium	rLiNa	2.889		2.968	0.079	1	2
F2SO	Thionyl Fluoride	rFS	1.585	±0.000	1.665	0.079	1	3
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.211	0.081	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.710	0.107	1	3
Al2Cl6	Aluminum, di-μ-chlorotetrachlorodi-	rAlCl	2.040	±0.040	2.320	0.280	1	3
C4H10O	Methyl propyl ether	rCH	1.099		1.428	0.329	1	2

255 molecules.