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 MP4=FULL/6-311G**

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.098	-0.432	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.002	-0.075	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.721	-0.054	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.226	-0.039	1	2
C5H8O	Methyl cyclopropyl ketone	rCH	1.126		1.093	-0.033	3	7
CrH	Chromium hydride	rHCr	1.655	±0.001	1.623	-0.032	1	2
C2H	Ethynyl radical	rC#C	1.217		1.187	-0.030	1	2
SiC	silicon monocarbide	rCSi	1.722		1.703	-0.019	1	2
LiOH	lithium hydroxide	rOH	0.969		0.951	-0.018	1	3
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.303	-0.018	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.463	-0.017	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.100	-0.017	1	5
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.101	-0.015	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.139	-0.014	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.278	-0.014	1	2
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.315	-0.014	1	4
FO	Oxygen monofluoride	rFO	1.354		1.341	-0.014	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.361	-0.013	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.092	-0.013	1	7
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.464	-0.011	1	2
C5H8	Ethenylcyclopropane	rCH	1.099		1.089	-0.010	1	6
B2H6	Diborane	rBH	1.200		1.191	-0.009	1	5
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.095	-0.008	1	6
HO2	Hydroperoxy radical	rOO	1.331		1.323	-0.007	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.470	-0.006	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.469	-0.006	1	3
LiNH2	lithium amide	rLiN	1.736	±0.003	1.731	-0.005	1	2
CH2NH	Methanimine	rCH	1.103		1.098	-0.005	1	3
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.339	-0.005	2	3
LiOH	lithium hydroxide	rLiO	1.582		1.577	-0.005	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.475	-0.005	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.016	-0.004	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.912	-0.004	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.500	-0.004	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.444	-0.004	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.101	-0.004	2	8
CF3COOH	trifluoroacetic acid	rCC	1.546	±0.005	1.542	-0.004	1	2
HCCl	Chloromethylene	rCH	1.119	±0.036	1.115	-0.003	1	3
CH2	Methylene	rCH	1.085		1.082	-0.003	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.025	-0.003	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.312	-0.003	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.592	-0.003	1	2
BN	boron nitride	rB=N	1.325		1.322	-0.003	1	2
C10H8	Azulene	rC:C	1.414		1.412	-0.002	7	9
CH3OC2H5	Ethane, methoxy-	rCO	1.415	±0.005	1.413	-0.002	1	2
GeH	germylidene	rGeH	1.588		1.586	-0.002	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.788	-0.002	1	2
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.088	-0.002	1	3
CH3NH2	methyl amine	rNH	1.018	±0.001	1.016	-0.002	2	6
CH3NH2	methyl amine	rCN	1.471	±0.003	1.470	-0.001	1	2
BeH	beryllium monohydride	rBeH	1.343		1.342	-0.001	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.970	-0.001	1	3
H2Se	Hydrogen selenide	rSeH	1.460		1.459	-0.001	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.459	-0.001	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.414	-0.001	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.096	0.000	1	5
B2H6	Diborane	rBH	1.320		1.320	0.000	1	3
CH2CO	Ketene	rCH	1.083		1.082	0.000	1	4
OH	Hydroxyl radical	rOH	0.970		0.969	0.000	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.511	0.000	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.421	0.000	1	2
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.090	0.000	1	4
CH3CCH	propyne	rCH	1.096		1.096	0.000	1	5
CH3CH2CHO	Propanal	rCH	1.115		1.115	0.000	3	10
SiH2F2	difluorosilane	rSiH	1.462		1.462	0.001	1	4
H2	Hydrogen diatomic	rHH	0.741		0.742	0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.958	0.001	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.115	0.001	1	4
CH2CHCH2CH3	1-Butene	rCC	1.536		1.537	0.001	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.532	0.001	1	2
SiH	Silylidyne	rSiH	1.520		1.521	0.001	1	2
CH3NO	nitrosomethane	rCH	1.094		1.095	0.001	1	4
HS	Mercapto radical	rSH	1.341		1.342	0.001	1	2
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.328	0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.424	0.002	1	2
C5H6	Propellane	rCC	1.525	±0.002	1.527	0.002	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.277	0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.095	0.002	4	8
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.096	0.002	4	10
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.084	0.002	2	5
NaF	sodium fluoride	rNaF	1.926	±0.000	1.929	0.003	1	2
C4H8O2	Ethyl acetate	rCC	1.515		1.518	0.003	5	6
KH	Potassium hydride	rKH	2.243	±0.001	2.245	0.003	1	2
C3H8	Propane	rCH	1.096		1.099	0.003	1	4
BH3	boron trihydride	rBH	1.190		1.193	0.003	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.092	±0.007	1.095	0.003	4	11
C2H2	Acetylene	rCH	1.063		1.066	0.003	1	3
C3H3NO	Oxazole	rCO	1.370	±0.002	1.373	0.003	1	5
C3H6	Cyclopropane	rCH	1.083		1.086	0.003	1	4
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.088	0.003	1	2
HS-	mercapto anion	rSH	1.343		1.347	0.004	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.099	±0.007	1.103	0.004	1	6
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.095	0.004	2	5
C4H8	cyclobutane	rCH	1.093		1.097	0.004	1	5
CH3NO	nitrosomethane	rCH	1.092		1.096	0.004	1	5
CH3CH2CHO	Propanal	rCC	1.523		1.527	0.004	1	2
LiO	lithium oxide	rLiO	1.688		1.693	0.004	1	2
MgH	magnesium monohydride	rMgH	1.730		1.734	0.004	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.568	0.005	1	2
N3	azide radical	rNN	1.181		1.186	0.005	1	2
C4H8	cyclobutane	rCH	1.091		1.096	0.005	1	6
HOBr	Hypobromous acid	rOH	0.961		0.966	0.005	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.100	±0.003	1.105	0.005	3	8
C3H3NO	Oxazole	rCO	1.357	±0.003	1.362	0.005	1	2
C3H4	cyclopropene	rCH	1.088		1.093	0.005	1	6
C4H8O2	Ethyl acetate	rCC	1.508		1.513	0.005	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.082	0.005	1	3
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.653	0.006	1	2
CF	Fluoromethylidyne	rCF	1.276		1.282	0.006	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.098	0.006	3	6
CH3CCH	propyne	rCH	1.060		1.066	0.006	3	4
C3H3NO	Oxazole	rCH	1.075	±0.001	1.081	0.006	4	7
C3H3NO	Oxazole	rCH	1.073	±0.001	1.079	0.006	5	8
CH4	Methane	rCH	1.087	±0.001	1.093	0.006	1	2
BH	Boron monohydride	rBH	1.232		1.239	0.006	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.098	0.006	1	3
C3H3NO	Oxazole	rCH	1.075	±0.001	1.081	0.006	2	6
C5H8	Ethenylcyclopropane	rCC	1.475		1.481	0.006	1	2
C10H8	Azulene	rCH	1.084		1.091	0.007	4	14
C10H8	Azulene	rCH	1.080		1.086	0.007	9	17
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.138	0.007	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.093	0.007	2	5
BF	Boron monofluoride	rBF	1.267	±0.000	1.274	0.007	1	2
OH-	hydroxide anion	rOH	0.964		0.971	0.007	1	2
C10H8	Azulene	rC:C	1.398		1.406	0.008	1	3
C3H4	cyclopropene	rCH	1.072		1.080	0.008	2	4
CH3OC2H5	Ethane, methoxy-	rCH	1.089	±0.008	1.097	0.008	4	10
CH3OC2H5	Ethane, methoxy-	rCH	1.086	±0.010	1.094	0.008	1	5
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.178	0.008	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.260	0.008	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.517	0.008	2	3
CH3Br	methyl bromide	rCH	1.082	±0.001	1.090	0.008	1	3
C10H8	Azulene	rC:C	1.405	±0.001	1.413	0.008	2	9
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.097	0.009	4	6
C5H8O	Methyl cyclopropyl ketone	rCC	1.510		1.519	0.009	2	3
BO	boron monoxide	rB=O	1.205		1.214	0.009	1	2
C2H3	vinyl	rCH	1.085		1.094	0.009	2	4
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.777	0.010	1	4
CH3OC2H5	Ethane, methoxy-	rCO	1.407	±0.004	1.417	0.010	2	3
SiH3Cl	chlorosilane	rSiCl	2.051		2.060	0.010	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.944	0.010	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.103	0.010	1	3
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.339	0.010	1	2
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.683	0.010	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.317	0.010	1	2
C10H8	Azulene	rCH	1.081		1.092	0.010	1	11
C4H8O2	Ethyl acetate	rC=O	1.203		1.214	0.011	2	4
C10H8	Azulene	rCH	1.083		1.094	0.011	5	15
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.191	0.011	1	3
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.045	0.012	1	4
HCCl	Chloromethylene	rCCl	1.696	±0.003	1.709	0.013	1	2
NaH	sodium hydride	rNaH	1.887	±0.000	1.899	0.013	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.093	0.013	1	2
C3H6	Cyclopropane	rCC	1.501		1.514	0.013	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.510	0.013	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.624	0.013	1	2
NH2CONH2	Urea	rNH	0.998		1.011	0.014	4	8
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.939	0.014	1	4
CH2CO	Ketene	rC=O	1.162		1.176	0.014	2	3
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.238	0.014	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.507	0.014	2	3
C4H8O2	Ethyl acetate	rCO	1.345		1.359	0.014	2	3
CF3COOH	trifluoroacetic acid	rC=O	1.192	±0.003	1.206	0.014	2	4
OCSe	Carbonyl selenide	rC=Se	1.709		1.723	0.014	1	3
C2H2	Acetylene	rC#C	1.203		1.217	0.014	1	2
O2	Oxygen diatomic	rO=O	1.208		1.222	0.014	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.957	0.015	1	2
C5H6	Propellane	rCC	1.596	±0.005	1.611	0.015	2	5
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.790	0.016	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.793	0.016	1	4
CN-	cyanide anion	rC#N	1.177	±0.004	1.194	0.017	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.146	0.018	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.177	0.018	1	2
C2H	Ethynyl radical	rCH	1.047		1.066	0.019	1	3
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.380	0.019	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.975	0.020	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.118	0.021	1	2
CaH	Calcium monohydride	rCaH	2.003	±0.000	2.023	0.021	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.116	0.021	1	2
C10H8	Azulene	rC:C	1.484		1.505	0.021	7	8
C10H8	Azulene	rC:C	1.377		1.399	0.022	5	7
C3H5	Allyl radical	rCH	1.069		1.091	0.022	1	2
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.088	0.022	1	4
B2	Boron diatomic	rBB	1.590		1.614	0.024	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.676	0.025	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.578	0.025	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.720	0.025	1	3
SiF	silicon monofluoride	rSiF	1.604		1.630	0.025	1	2
NO+	nitric oxide cation	rN=O	1.066		1.092	0.027	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.143	0.027	1	2
F2	Fluorine diatomic	rFF	1.412		1.439	0.027	1	2
Li2	Lithium diatomic	rLiLi	2.673		2.702	0.029	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.609	0.030	1	2
F2SO	Thionyl Fluoride	rO=S	1.413	±0.000	1.442	0.030	1	2
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.724	0.032	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.464	0.033	1	2
P2	Phosphorus diatomic	rP#P	1.893		1.926	0.033	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.284	0.033	1	2
C5H8O	Cyclopentanone	rCC	1.504		1.537	0.033	2	3
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.700	0.034	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.048	0.036	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.182	0.036	2	4
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.676	0.037	1	2
SO	Sulfur monoxide	rS=O	1.481		1.519	0.038	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.634	0.038	1	3
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.685	0.039	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.584	0.039	1	4
As4	Arsenic tetramer	rAsAs	2.435		2.474	0.039	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.639	0.040	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.537	0.040	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.737	0.040	1	3
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.777	0.041	1	2
S2	Sulfur diatomic	rS=S	1.889		1.930	0.041	1	2
C2	Carbon diatomic	rC=C	1.243		1.284	0.041	1	2
HOBr	Hypobromous acid	rBrO	1.834		1.877	0.043	2	3
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.573	0.043	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.325	0.044	1	2
BrO	Bromine monoxide	rOBr	1.718		1.762	0.045	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.760	0.046	1	3
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.585	0.046	1	5
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.187	0.051	1	2
PS	phosphorus sulfide	rP=S	1.900		1.952	0.052	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.476	0.052	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.065	0.052	1	2
SCl	sulfur monochloride	rSCl	1.975		2.030	0.055	1	2
F2SO	Thionyl Fluoride	rFS	1.585	±0.000	1.641	0.056	1	3
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.816	0.057	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.526	0.059	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.688	0.060	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.049	0.061	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.670	0.063	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.518	0.070	5	6
BeO	beryllium oxide	rBe=O	1.331		1.413	0.082	1	2
GeO	Germanium monoxide	rOGe	1.625		1.720	0.096	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.810	0.097	1	4
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.747	0.144	1	3
Al2Cl6	Aluminum, di-μ-chlorotetrachlorodi-	rAlCl	2.040	±0.040	2.258	0.218	1	3
CaO	Calcium monoxide	rOCa	1.822		2.118	0.296	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.413	0.314	1	2

240 molecules.