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 CCSD/aug-cc-pVQZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
As4	Arsenic tetramer	rAsAs	2.435		2.406	-0.029	1	2
HOBr	Hypobromous acid	rBrO	1.834		1.810	-0.024	2	3
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.511	-0.024	1	2
LiOH	lithium hydroxide	rOH	0.969		0.946	-0.023	1	3
F2	Fluorine diatomic	rFF	1.412		1.390	-0.022	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.575	-0.021	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.587	-0.020	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.456	-0.019	1	2
GeH	germylidene	rGeH	1.588		1.570	-0.018	1	2
HF+	hydrogen fluoride cation	rHF	1.014		0.998	-0.016	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.016	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.624	-0.016	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.775	-0.015	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.744	-0.015	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.637	-0.014	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.152	-0.014	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.739	-0.014	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.143	-0.014	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.145	-0.013	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.684	-0.013	1	3
C2H	Ethynyl radical	rC#C	1.217		1.203	-0.013	1	2
HCCl	Chloromethylene	rCH	1.119	±0.036	1.106	-0.013	1	3
FO	Oxygen monofluoride	rFO	1.354		1.341	-0.013	1	2
GeO	Germanium monoxide	rOGe	1.625		1.612	-0.012	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.961	-0.012	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.280	-0.012	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.733	-0.012	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.066	-0.012	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.105	-0.011	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.914	-0.011	1	4
HS+	sulfur monohydride cation	rSH	1.374		1.363	-0.011	1	2
O2	Oxygen diatomic	rO=O	1.208		1.197	-0.011	1	2
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.725	-0.011	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.143	-0.010	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.320	-0.010	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.764	-0.010	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.666	-0.010	1	2
N3	azide radical	rNN	1.181		1.171	-0.010	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.925	-0.009	1	2
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.081	-0.009	1	3
PS	phosphorus sulfide	rP=S	1.900		1.891	-0.009	1	2
NO+	nitric oxide cation	rN=O	1.066		1.057	-0.009	1	2
CH2	Methylene	rCH	1.085		1.076	-0.009	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.020	-0.009	1	2
CN	Cyano radical	rC#N	1.172		1.163	-0.009	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.657	-0.008	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.082	-0.008	1	3
H2Se	Hydrogen selenide	rSeH	1.460		1.452	-0.008	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.440	-0.008	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.517	-0.008	1	3
CH2PH	Phosphaethene	rCH	1.090	±0.015	1.082	-0.008	1	4
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.723	-0.008	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.005	-0.007	1	2
BeO	beryllium oxide	rBe=O	1.331		1.324	-0.007	1	2
CH2CO	Ketene	rCH	1.083		1.075	-0.007	1	4
BrO	Bromine monoxide	rOBr	1.718		1.711	-0.007	1	2
BN	boron nitride	rB=N	1.325		1.318	-0.007	1	2
SiC	silicon monocarbide	rCSi	1.722		1.715	-0.007	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.414	-0.007	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.109	-0.007	1	2
CF	Fluoromethylidyne	rCF	1.276		1.270	-0.007	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.275	-0.006	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.409	-0.006	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.689	-0.006	1	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.547	-0.006	1	2
CH2CO	Ketene	rC=O	1.162		1.156	-0.006	2	3
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.492	-0.005	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.486	-0.005	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.339	-0.005	2	3
SO+	sulfur monoxide cation	rO=S	1.424		1.420	-0.004	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.093	-0.004	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.624	-0.004	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.452	-0.004	1	2
P2	Phosphorus diatomic	rP#P	1.893		1.889	-0.004	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.220	-0.004	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.081	-0.004	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.511	-0.004	1	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.458	-0.004	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.125	-0.004	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.608	-0.003	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.596	-0.003	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.174	-0.003	1	2
BO	boron monoxide	rB=O	1.205		1.201	-0.003	1	2
HCCl	Chloromethylene	rCCl	1.696	±0.003	1.693	-0.003	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.968	-0.003	1	3
OH-	hydroxide anion	rOH	0.964		0.961	-0.003	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.882	-0.003	2	3
C2H2	Acetylene	rC#C	1.203		1.200	-0.002	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.265	-0.002	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.528	-0.002	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.474	-0.002	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.134	-0.002	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.915	-0.002	1	2
H2O	Water	rOH	0.958	±0.000	0.956	-0.002	1	2
OH	Hydroxyl radical	rOH	0.970		0.968	-0.002	1	2
SO	Sulfur monoxide	rS=O	1.481		1.480	-0.002	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.473	-0.002	1	3
SiH3F	monofluorosilane	rSiH	1.476		1.475	-0.001	1	3
CH	Methylidyne	rCH	1.120		1.119	-0.001	1	2
C2H2	Acetylene	rCH	1.063		1.062	-0.001	1	3
BH3	boron trihydride	rBH	1.190		1.189	-0.001	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.479	-0.001	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.352	-0.001	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.257	-0.001	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.766	-0.001	1	4
HOBr	Hypobromous acid	rOH	0.961		0.961	0.000	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.350	0.000	1	4
PF2	Phosphorus difluoride	rPF	1.579		1.579	0.000	1	2
C2	Carbon diatomic	rC=C	1.243		1.242	0.000	1	2
CH4	Methane	rCH	1.087	±0.001	1.087	0.000	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.709	0.000	1	3
BH	Boron monohydride	rBH	1.232		1.232	0.000	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.082	0.000	1	3
HCl+	hydrogen chloride cation	rHCl	1.315		1.315	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
HS	Mercapto radical	rSH	1.341		1.342	0.001	1	2
HS-	mercapto anion	rSH	1.343		1.344	0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.423	0.001	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.275	0.001	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.892	0.001	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.930	0.001	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.165	0.001	1	2
S2	Sulfur diatomic	rS=S	1.889		1.891	0.002	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.506	0.002	1	2
SiH	Silylidyne	rSiH	1.520		1.522	0.002	1	2
SiF	silicon monofluoride	rSiF	1.604		1.607	0.002	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.087	0.003	1	2
BeH	beryllium monohydride	rBeH	1.343		1.346	0.003	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.598	0.003	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.331	0.004	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.063	0.005	1	3
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.101	0.005	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.467	0.005	1	4
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.596	0.006	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.861	0.006	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.019	0.006	1	2
Cl2	Chlorine diatomic	rClCl	1.988		1.995	0.007	1	2
B2	Boron diatomic	rBB	1.590		1.598	0.008	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.059	0.008	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.745	0.009	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.620	0.009	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.664	0.009	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.071	0.009	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.592	0.010	1	2
SCl	sulfur monochloride	rSCl	1.975		1.985	0.010	1	2
LiO	lithium oxide	rLiO	1.688		1.700	0.012	1	2
MgH	magnesium monohydride	rMgH	1.730		1.742	0.012	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.577	0.013	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.608	0.013	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.969	0.014	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.081	0.014	1	2
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.145	0.015	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.791	0.016	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.311	0.016	1	2
C2H	Ethynyl radical	rCH	1.047		1.062	0.016	1	3
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.189	0.018	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.040	0.019	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.739	0.025	1	3
Li2	Lithium diatomic	rLiLi	2.673		2.699	0.026	1	2
NaH	sodium hydride	rNaH	1.887	±0.000	1.926	0.040	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.403	0.042	1	2
NaLi	lithium sodium	rLiNa	2.889		2.950	0.061	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.990	0.064	1	2

165 molecules.