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
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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 CCSD=FULL/aug-cc-pVQZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
Na2	Sodium diatomic	rNaNa	3.079		2.234	-0.845	1	2
NaH	sodium hydride	rNaH	1.887	±0.000	1.568	-0.319	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.737	-0.188	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.278	-0.082	1	2
NaLi	lithium sodium	rLiNa	2.889		2.829	-0.060	1	2
Li2	Lithium diatomic	rLiLi	2.673		2.626	-0.047	1	2
GeH	germylidene	rGeH	1.588		1.543	-0.045	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.492	-0.042	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.813	-0.042	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.918	-0.037	1	2
HNO3	Nitric acid	rNO	1.406		1.375	-0.031	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.744	-0.031	1	2
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.101	-0.029	1	2
HOBr	Hypobromous acid	rBrO	1.834		1.805	-0.029	2	3
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.570	-0.026	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.269	-0.026	1	2
LiOH	lithium hydroxide	rOH	0.969		0.943	-0.026	1	3
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.450	-0.025	1	2
F2	Fluorine diatomic	rFF	1.412		1.387	-0.025	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.571	-0.024	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.501	-0.024	1	3
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.583	-0.024	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.491	-0.024	1	3
GeF	Germanium monofluoride	rFGe	1.745		1.722	-0.023	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.753	-0.022	1	2
GeO	Germanium monoxide	rOGe	1.625		1.604	-0.021	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.716	-0.020	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.619	-0.020	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.562	-0.019	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.635	-0.019	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.633	-0.019	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.679	-0.018	1	3
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.059	-0.018	1	2
SiC	silicon monocarbide	rCSi	1.722		1.704	-0.018	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.741	-0.018	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.735	-0.018	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.335	-0.018	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.303	-0.018	1	2
HF+	hydrogen fluoride cation	rHF	1.014		0.997	-0.017	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.140	-0.017	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.648	-0.017	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.908	-0.017	1	4
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	1.995	-0.017	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.149	-0.017	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.714	-0.017	1	2
HCCl	Chloromethylene	rCH	1.119	±0.036	1.102	-0.016	1	3
C2H	Ethynyl radical	rC#C	1.217		1.200	-0.016	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.143	-0.016	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.514	-0.016	1	2
FO	Oxygen monofluoride	rFO	1.354		1.338	-0.016	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.775	-0.015	1	2
BeO	beryllium oxide	rBe=O	1.331		1.316	-0.015	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.445	-0.015	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.462	-0.015	1	3
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.278	-0.014	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.662	-0.014	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.959	-0.014	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.466	-0.014	1	2
PS	phosphorus sulfide	rP=S	1.900		1.886	-0.014	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.103	-0.013	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.317	-0.013	1	2
SiH	Silylidyne	rSiH	1.520		1.507	-0.013	1	2
O2	Oxygen diatomic	rO=O	1.208		1.194	-0.013	1	2
N3	azide radical	rNN	1.181		1.168	-0.013	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.141	-0.013	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.362	-0.012	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.492	-0.012	1	2
LiO	lithium oxide	rLiO	1.688		1.676	-0.012	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.436	-0.012	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.152	-0.012	1	2
BrO	Bromine monoxide	rOBr	1.718		1.706	-0.012	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.552	-0.012	1	2
CN	Cyano radical	rC#N	1.172		1.160	-0.012	1	2
CH2	Methylene	rCH	1.085		1.074	-0.011	1	2
BN	boron nitride	rB=N	1.325		1.314	-0.011	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.270	-0.011	1	2
NO+	nitric oxide cation	rN=O	1.066		1.055	-0.011	1	2
CF	Fluoromethylidyne	rCF	1.276		1.265	-0.011	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.080	-0.011	1	3
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.404	-0.011	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.018	-0.010	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.450	-0.010	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.685	-0.010	1	3
HCCl	Chloromethylene	rCCl	1.696	±0.003	1.687	-0.009	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.482	-0.009	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.106	-0.009	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.412	-0.009	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.545	-0.008	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.453	-0.008	1	4
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.489	-0.008	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.620	-0.008	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.454	-0.008	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.217	-0.008	1	2
P2	Phosphorus diatomic	rP#P	1.893		1.886	-0.007	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.417	-0.007	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.449	-0.007	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.260	-0.007	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.503	-0.007	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.091	-0.007	1	2
BO	boron monoxide	rB=O	1.205		1.198	-0.007	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.878	-0.006	2	3
SF	Monosulfur monofluoride	rSF	1.599		1.593	-0.006	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.130	-0.006	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.605	-0.006	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.171	-0.006	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.122	-0.006	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.470	-0.006	1	2
SiF	silicon monofluoride	rSiF	1.604		1.599	-0.006	1	2
MgH	magnesium monohydride	rMgH	1.730		1.724	-0.006	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.703	-0.006	1	3
BH	Boron monohydride	rBH	1.232		1.227	-0.005	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.574	-0.005	1	2
C2H2	Acetylene	rC#C	1.203		1.197	-0.005	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.077	-0.005	1	4
PH	phosphorus monohydride	rPH	1.422		1.417	-0.005	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.925	-0.005	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.966	-0.005	1	3
SO	Sulfur monoxide	rS=O	1.481		1.477	-0.005	1	2
BH3	boron trihydride	rBH	1.190		1.186	-0.004	1	2
OH-	hydroxide anion	rOH	0.964		0.960	-0.004	1	2
CH	Methylidyne	rCH	1.120		1.116	-0.004	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.590	-0.004	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.347	-0.004	1	4
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.017	-0.004	1	2
C2H2	Acetylene	rCH	1.063		1.059	-0.004	1	3
C2	Carbon diatomic	rC=C	1.243		1.239	-0.004	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.254	-0.004	1	2
BeH	beryllium monohydride	rBeH	1.343		1.339	-0.003	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.888	-0.003	1	2
H2O	Water	rOH	0.958	±0.000	0.955	-0.003	1	2
OH	Hydroxyl radical	rOH	0.970		0.967	-0.003	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.167	-0.003	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.914	-0.003	1	2
CH4	Methane	rCH	1.087	±0.001	1.085	-0.002	1	2
HOBr	Hypobromous acid	rOH	0.961		0.959	-0.002	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.588	-0.002	1	2
S2	Sulfur diatomic	rS=S	1.889		1.887	-0.002	1	2
HS	Mercapto radical	rSH	1.341		1.339	-0.002	1	2
HS-	mercapto anion	rSH	1.343		1.342	-0.002	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.313	-0.001	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.058	-0.001	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.076	-0.001	2	5
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.274	-0.001	1	2
B2	Boron diatomic	rBB	1.590		1.590	0.000	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.095	0.000	1	2
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.326	0.000	1	2
H2	Hydrogen diatomic	rHH	0.741		0.742	0.000	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.081	0.001	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.085	0.001	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.063	0.002	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.015	0.002	1	2
Cl2	Chlorine diatomic	rClCl	1.988		1.991	0.003	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.614	0.003	1	2
SCl	sulfur monochloride	rSCl	1.975		1.981	0.006	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.074	0.007	1	2
C2H	Ethynyl radical	rCH	1.047		1.060	0.013	1	3
CFCl	chlorofluoromethylene	rCCl	1.714		1.732	0.018	1	3

157 molecules.