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
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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/aug-cc-pVTZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C2H2O2	Ethanedial	rCH	1.132		1.098	-0.034	1	3
ScH	Scandium monohydride	rScH	1.775	±0.000	1.744	-0.032	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.238	-0.027	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.095	-0.022	1	5
BeH	beryllium monohydride	rBeH	1.343		1.321	-0.022	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.514	-0.021	1	2
LiOH	lithium hydroxide	rOH	0.969		0.948	-0.021	1	3
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.457	-0.018	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.513	-0.017	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.016	1	2
B2H6	Diborane	rBH	1.200		1.184	-0.016	1	5
As4	Arsenic tetramer	rAsAs	2.435		2.420	-0.015	1	2
GeH	germylidene	rGeH	1.588		1.573	-0.015	1	2
CH2NH	Methanimine	rCH	1.103		1.089	-0.014	1	3
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.408	-0.013	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.279	-0.013	1	2
C5H6	Propellane	rCC	1.596	±0.005	1.584	-0.012	2	5
HF+	hydrogen fluoride cation	rHF	1.014		1.002	-0.012	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.341	-0.012	1	2
C2H2O2	Ethanedial	rCC	1.526		1.514	-0.012	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.468	-0.012	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.437	-0.011	1	2
B2H6	Diborane	rBH	1.320		1.309	-0.011	1	3
NaLi	lithium sodium	rLiNa	2.889		2.878	-0.011	1	2
CH2	Methylene	rCH	1.085		1.074	-0.011	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.103	-0.011	1	4
HS+	sulfur monohydride cation	rSH	1.374		1.364	-0.010	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.500	-0.010	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.080	-0.010	1	3
C5H6	Propellane	rCC	1.525	±0.002	1.515	-0.010	1	2
CH	Methylidyne	rCH	1.120		1.110	-0.010	1	2
BH	Boron monohydride	rBH	1.232		1.223	-0.009	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.522	-0.009	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.009	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.406	-0.008	1	2
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.665	-0.008	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.452	-0.008	1	2
CH2CO	Ketene	rCH	1.083		1.075	-0.008	1	4
NH4+	ammonium cation	rHN	1.029	±0.000	1.022	-0.007	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.918	-0.007	1	4
C2H	Ethynyl radical	rC#C	1.217		1.210	-0.007	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.464	-0.007	1	2
CH3CCH	propyne	rCH	1.096		1.089	-0.007	1	5
CH3NH2	methyl amine	rNH	1.018	±0.001	1.012	-0.006	2	6
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.508	-0.006	1	3
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.085	-0.006	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.491	-0.006	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.730	-0.006	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.519	-0.006	1	3
CH3NO	nitrosomethane	rCH	1.094		1.088	-0.006	1	4
CH3CH2SH	ethanethiol	rCH	1.095		1.090	-0.005	1	4
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.080	-0.005	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.591	-0.005	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.078	-0.004	1	4
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.340	-0.004	2	3
C2H2+	acetylene cation	rCH	1.077	±0.005	1.073	-0.004	1	3
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.930	-0.004	1	2
C3H4	cyclopropene	rCH	1.088		1.084	-0.004	1	6
MgH	magnesium monohydride	rMgH	1.730		1.726	-0.003	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.592	-0.003	1	2
C4H8	cyclobutane	rCH	1.093		1.091	-0.003	1	5
C4H8	cyclobutane	rCH	1.091		1.088	-0.003	1	6
CH3CH2SH	ethanethiol	rCH	1.090		1.087	-0.003	2	7
LiOH	lithium hydroxide	rLiO	1.582		1.579	-0.003	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.156	-0.002	1	2
CH3NO	nitrosomethane	rCH	1.092		1.090	-0.002	1	5
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.751	-0.002	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.465	-0.002	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.251	-0.002	1	2
CF	Fluoromethylidyne	rCF	1.276		1.274	-0.002	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.169	-0.002	1	2
CH3CH2SH	ethanethiol	rCH	1.092		1.090	-0.002	1	5
CH3CCH	propyne	rCH	1.060		1.058	-0.002	3	4
N3	azide radical	rNN	1.181		1.180	-0.002	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.475	-0.001	1	3
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.179	-0.001	1	3
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.758	-0.001	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.314	0.000	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.475	0.000	1	3
C3H4	cyclopropene	rCH	1.072		1.072	0.000	2	4
NO+	nitric oxide cation	rN=O	1.066		1.066	0.000	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.695	0.000	1	3
HS	Mercapto radical	rSH	1.341		1.341	0.000	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.709	0.000	1	3
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.731	0.000	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.154	0.000	1	2
CH2CHF	Ethene, fluoro-	rCH	1.077		1.077	0.000	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.083	0.000	1	3
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.855	0.000	1	2
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.693	0.000	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.275	0.001	1	2
CH4	Methane	rCH	1.087	±0.001	1.088	0.001	1	2
HS-	mercapto anion	rSH	1.343		1.344	0.001	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.225	0.001	1	2
OH-	hydroxide anion	rOH	0.964		0.965	0.001	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.972	0.001	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.087	0.001	2	5
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.158	0.001	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.481	0.001	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.641	0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.082	0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.424	0.001	1	2
H2	Hydrogen diatomic	rHH	0.741		0.743	0.002	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.094	0.002	1	3
CH2CO	Ketene	rC=O	1.162		1.164	0.002	2	3
BrO	Bromine monoxide	rOBr	1.718		1.719	0.002	1	2
O2	Oxygen diatomic	rO=O	1.208		1.209	0.002	1	2
F2	Fluorine diatomic	rFF	1.412		1.414	0.002	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.919	0.002	1	2
C2H3	vinyl	rCH	1.085		1.088	0.003	2	4
N2	Nitrogen diatomic	rN#N	1.098		1.100	0.003	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.463	0.003	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.507	0.003	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.739	0.003	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.770	0.003	1	4
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.081	0.003	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.087	0.003	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.180	0.003	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.167	0.003	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.749	0.003	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.132	0.004	1	2
SiH	Silylidyne	rSiH	1.520		1.524	0.004	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.335	0.004	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.611	0.004	1	2
LiO	lithium oxide	rLiO	1.688		1.692	0.004	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.466	0.004	1	4
NSe	Nitrogen monoselenide	rN=Se	1.652		1.656	0.005	1	2
C2	Carbon diatomic	rC=C	1.243		1.247	0.005	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.333	0.005	1	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.558	0.005	1	2
BN	boron nitride	rB=N	1.325		1.330	0.005	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.171	0.005	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.356	0.006	1	4
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.026	0.006	1	2
FO	Oxygen monofluoride	rFO	1.354		1.360	0.006	1	2
BO	boron monoxide	rB=O	1.205		1.211	0.006	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.781	0.006	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.672	0.007	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.933	0.007	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.704	0.007	1	3
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.684	0.008	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.618	0.008	1	2
C2H	Ethynyl radical	rCH	1.047		1.056	0.010	1	3
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.022	0.010	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.966	0.011	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.372	0.011	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.293	0.011	1	2
GeO	Germanium monoxide	rOGe	1.625		1.636	0.012	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.658	0.012	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.503	0.013	1	2
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.510	0.013	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.592	0.013	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.577	0.013	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.613	0.013	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.608	0.013	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.559	0.014	1	4
SiH3Cl	chlorosilane	rSiCl	2.051		2.065	0.014	1	2
SiF	silicon monofluoride	rSiF	1.604		1.620	0.016	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.152	0.016	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.162	0.016	2	4
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.050	0.017	1	4
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.527	0.017	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.079	0.017	1	2
SO	Sulfur monoxide	rS=O	1.481		1.498	0.017	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.493	0.017	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.608	0.018	1	2
PS	phosphorus sulfide	rP=S	1.900		1.918	0.018	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.948	0.019	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.675	0.020	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.088	0.021	1	2
S2	Sulfur diatomic	rS=S	1.889		1.910	0.021	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.478	0.022	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.274	0.023	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.012	0.025	1	2
SCl	sulfur monochloride	rSCl	1.975		2.000	0.025	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.910	0.026	2	3
CFCl	chlorofluoromethylene	rCCl	1.714		1.746	0.032	1	3

179 molecules.