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 B2PLYP=FULLultrafine/6-311G**

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.093	-0.437	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.990	-0.088	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.618	-0.033	1	2
C2H2O2	Ethanedial	rCH	1.132		1.106	-0.026	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.096	-0.021	1	5
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.244	-0.020	1	2
LiOH	lithium hydroxide	rOH	0.969		0.951	-0.019	1	3
C4H8O2	Ethyl acetate	rCH	1.105		1.087	-0.018	1	7
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.311	-0.018	1	4
B2H6	Diborane	rBH	1.200		1.186	-0.014	1	5
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.466	-0.014	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.091	-0.012	1	6
HF+	hydrogen fluoride cation	rHF	1.014		1.002	-0.012	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.724	-0.012	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.309	-0.012	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.570	-0.011	1	2
C2H	Ethynyl radical	rC#C	1.217		1.206	-0.011	1	2
C8H8	cubane	rCH	1.097		1.089	-0.008	1	9
HS+	sulfur monohydride cation	rSH	1.374		1.366	-0.008	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.526	-0.008	1	2
CH2NH	Methanimine	rCH	1.103		1.095	-0.008	1	3
C5H6	Propellane	rCC	1.596	±0.005	1.588	-0.008	2	5
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.097	-0.008	2	8
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.468	-0.007	1	2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.648	-0.007	1	2
CH2	Methylene	rCH	1.085		1.078	-0.007	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.465	-0.006	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.520	-0.005	1	3
B2H6	Diborane	rBH	1.320		1.315	-0.005	1	3
C5H6	Propellane	rCC	1.525	±0.002	1.520	-0.005	1	2
FO	Oxygen monofluoride	rFO	1.354		1.349	-0.005	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.091	-0.005	1	5
CH3NH2	methyl amine	rNH	1.018	±0.001	1.013	-0.005	2	6
NH4+	ammonium cation	rHN	1.029	±0.000	1.024	-0.004	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.086	-0.004	1	3
CH3CCH	propyne	rCH	1.096		1.092	-0.004	1	5
CH2CO	Ketene	rCH	1.083		1.078	-0.004	1	4
CH3CH2CHO	Propanal	rCH	1.115		1.111	-0.004	3	10
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.087	-0.004	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.560	-0.003	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.111	-0.003	1	4
CH3NO	nitrosomethane	rCH	1.094		1.091	-0.003	1	4
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.289	-0.003	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.250	-0.003	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.095	-0.003	2	6
C2H2O2	Ethanedial	rCC	1.526		1.523	-0.003	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.473	-0.002	1	3
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.091	-0.002	4	8
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.019	-0.002	1	2
C4H8O2	Ethyl acetate	rCC	1.515		1.513	-0.002	5	6
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.092	-0.002	4	10
SiH3F	monofluorosilane	rSiH	1.476		1.474	-0.002	1	3
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.080	-0.002	2	5
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.083	-0.002	1	2
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.409	-0.002	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.089	-0.002	2	5
CH2CHCH2CH3	1-Butene	rCC	1.536		1.534	-0.002	1	2
C3H8	Propane	rCH	1.096		1.095	-0.001	1	4
C4H8O2	Ethyl acetate	rCC	1.508		1.507	-0.001	1	2
CH3CHS	Thioacetaldehyde	rCH	1.090		1.089	-0.001	2	5
SiH4	Silane	rSiH	1.480	±0.000	1.479	-0.001	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.530	-0.001	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.496	-0.001	1	2
C2H2	Acetylene	rCH	1.063		1.062	-0.001	1	3
C4H8	cyclobutane	rCH	1.093		1.092	-0.001	1	5
F2	Fluorine diatomic	rFF	1.412		1.411	-0.001	1	2
C3H6	Cyclopropane	rCH	1.083		1.082	-0.001	1	4
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.916	-0.001	1	2
H2	Hydrogen diatomic	rHH	0.741		0.741	0.000	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.099	0.000	2	6
C4H8	cyclobutane	rCH	1.091		1.091	0.000	1	6
CH3NO	nitrosomethane	rCH	1.092		1.092	0.000	1	5
KH	Potassium hydride	rKH	2.243	±0.001	2.243	0.000	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.509	0.000	2	3
BH	Boron monohydride	rBH	1.232		1.233	0.000	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.344	0.000	2	3
CH3CH2CHO	Propanal	rCC	1.523		1.524	0.001	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.083	0.001	1	4
OCSe	Carbonyl selenide	rC=O	1.159		1.159	0.001	1	2
OH	Hydroxyl radical	rOH	0.970		0.970	0.001	1	2
N3	azide radical	rNN	1.181		1.182	0.001	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.330	0.001	1	2
C3H4	cyclopropene	rCH	1.088		1.089	0.001	1	6
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.225	0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
CF	Fluoromethylidyne	rCF	1.276		1.277	0.001	1	2
CH3CCH	propyne	rCH	1.060		1.061	0.001	3	4
NO	Nitric oxide	rN=O	1.154	±0.000	1.155	0.001	1	2
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.182	0.002	1	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.094	0.002	3	6
C2H2	Acetylene	rC#C	1.203		1.204	0.002	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.117	0.002	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.792	0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.094	0.002	1	3
BO	boron monoxide	rB=O	1.205		1.207	0.002	1	2
CH2CO	Ketene	rC=O	1.162		1.164	0.002	2	3
C2H2+	acetylene cation	rCH	1.077	±0.005	1.079	0.002	1	3
CH4	Methane	rCH	1.087	±0.001	1.089	0.002	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.089	0.003	2	5
CH	Methylidyne	rCH	1.120		1.123	0.003	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.092	0.003	1	4
CH3Br	methyl bromide	rCH	1.082	±0.001	1.085	0.003	1	3
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.174	0.003	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.507	0.003	1	2
C3H4	cyclopropene	rCH	1.072		1.075	0.003	2	4
H2Se	Hydrogen selenide	rSeH	1.460		1.463	0.003	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.132	0.004	1	2
NO+	nitric oxide cation	rN=O	1.066		1.069	0.004	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.757	0.004	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
PH	phosphorus monohydride	rPH	1.422		1.426	0.004	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.452	0.004	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.501	0.004	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.089	0.004	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.081	0.004	2	5
C4H8O2	Ethyl acetate	rC=O	1.203		1.207	0.004	2	4
SiH2F2	difluorosilane	rSiH	1.462		1.466	0.004	1	4
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.092	0.004	4	6
HCl+	hydrogen chloride cation	rHCl	1.315		1.319	0.004	1	2
CN	Cyano radical	rC#N	1.172		1.176	0.005	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.419	0.005	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.516	0.005	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.616	0.005	1	2
C10H8	naphthalene	rC:C	1.410		1.416	0.006	2	3
GeH	germylidene	rGeH	1.588		1.594	0.006	1	2
SiH	Silylidyne	rSiH	1.520		1.526	0.006	1	2
HS-	mercapto anion	rSH	1.343		1.349	0.006	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.090	0.006	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.104	0.006	1	2
C3H6	Cyclopropane	rCC	1.501		1.507	0.006	1	2
O2	Oxygen diatomic	rO=O	1.208		1.214	0.006	1	2
HNO3	Nitric acid	rNO	1.406		1.412	0.006	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.281	0.006	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.100	0.007	1	3
C4H8O2	Ethyl acetate	rCO	1.345		1.352	0.007	2	3
C2H3	vinyl	rCH	1.085		1.092	0.007	2	4
CH2CHCH2CH3	1-Butene	rCC	1.493		1.502	0.009	2	3
OCSe	Carbonyl selenide	rC=Se	1.709		1.718	0.009	1	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.562	0.009	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.430	0.009	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.360	0.009	1	4
OH-	hydroxide anion	rOH	0.964		0.973	0.009	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.338	0.010	1	3
MgH	magnesium monohydride	rMgH	1.730		1.740	0.010	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.657	0.010	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.525	0.010	1	3
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.705	0.010	1	3
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.689	0.013	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.475	0.013	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.955	0.013	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.504	0.013	1	2
NaLi	lithium sodium	rLiNa	2.889		2.903	0.014	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.781	0.014	1	4
PF5	Phosphorus pentafluoride	rFP	1.577		1.593	0.016	1	5
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.689	0.016	1	2
PS	phosphorus sulfide	rP=S	1.900		1.916	0.016	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.483	0.016	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.941	0.016	1	4
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.083	0.017	1	4
C2H	Ethynyl radical	rCH	1.047		1.063	0.017	1	3
CaC	Calcium monocarbide	rC#Ca	2.302		2.318	0.017	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.951	0.017	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.275	0.017	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.527	0.018	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.947	0.018	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.874	0.019	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.053	0.020	1	4
C3O2	Carbon suboxide	rC=O	1.146		1.166	0.020	2	4
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.794	0.020	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.071	0.020	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.797	0.020	1	4
GeO	Germanium monoxide	rOGe	1.625		1.645	0.020	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.445	0.021	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.617	0.022	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.618	0.022	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.498	0.022	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.035	0.023	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.274	0.023	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.120	0.024	1	2
SiF	silicon monofluoride	rSiF	1.604		1.630	0.026	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.757	0.026	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.298	0.026	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.462	0.027	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.772	0.027	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.635	0.028	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.563	0.029	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.619	0.029	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.091	0.029	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.623	0.029	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.609	0.029	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.684	0.030	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.326	0.031	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.462	0.031	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.697	0.031	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.099	0.032	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.189	0.032	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.672	0.032	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.731	0.033	1	3
SSO	Disulfur monoxide	rS=O	1.456		1.490	0.034	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.634	0.034	1	2
SO	Sulfur monoxide	rS=O	1.481		1.516	0.035	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.116	0.036	1	2
S2	Sulfur diatomic	rS=S	1.889		1.925	0.036	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.203	0.037	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.390	0.037	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.202	0.038	1	2
BrO	Bromine monoxide	rOBr	1.718		1.756	0.038	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.320	0.039	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.636	0.040	1	3
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.585	0.040	1	4
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.687	0.041	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.651	0.041	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.927	0.042	2	3
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.575	0.045	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.182	0.046	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.806	0.047	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.677	0.049	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.588	0.049	1	5
SCl	sulfur monochloride	rSCl	1.975		2.025	0.050	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.942	0.051	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.767	0.053	1	3
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.113	0.054	1	3
CaO	Calcium monoxide	rOCa	1.822		1.878	0.056	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.513	0.065	5	6
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.786	0.073	1	4
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.708	0.105	1	3
C4H10O	Methyl propyl ether	rCH	1.099		1.410	0.311	1	2

228 molecules.