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 B97D3/cc-pVQZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.992	-0.086	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.278	-0.024	1	2
C2H2O2	Ethanedial	rCH	1.132		1.113	-0.019	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.098	-0.019	1	5
CaO	Calcium monoxide	rOCa	1.822		1.805	-0.017	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.089	-0.016	1	7
LiOH	lithium hydroxide	rOH	0.969		0.953	-0.016	1	3
CH3CH2CHO	Propanal	rCH	1.103		1.093	-0.010	1	6
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.587	-0.009	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.488	-0.009	1	2
B2H6	Diborane	rBH	1.200		1.193	-0.007	1	5
C8H8	cubane	rCH	1.097		1.090	-0.007	1	9
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.314	-0.006	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.785	-0.005	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.101	-0.004	2	8
CH3CH2OH	Ethanol	rCH	1.098		1.094	-0.004	1	6
NH4+	ammonium cation	rHN	1.029	±0.000	1.025	-0.003	1	2
CH2NH	Methanimine	rCH	1.103		1.100	-0.003	1	3
CH3NH2	methyl amine	rCN	1.471	±0.003	1.468	-0.003	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.970	-0.003	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.093	-0.003	1	5
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.591	-0.003	1	2
F2	Fluorine diatomic	rFF	1.412		1.409	-0.003	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.016	-0.002	2	6
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.251	-0.001	1	2
CN	Cyano radical	rC#N	1.172		1.170	-0.001	1	2
NO+	nitric oxide cation	rN=O	1.066		1.065	-0.001	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.089	-0.001	1	3
HS+	sulfur monohydride cation	rSH	1.374		1.373	-0.001	1	2
CH3CCH	propyne	rCH	1.096		1.095	-0.001	1	5
CH2CO	Ketene	rCH	1.083		1.082	0.000	1	4
N3	azide radical	rNN	1.181		1.181	0.000	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.292	0.000	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.153	0.000	1	2
C4H8O2	Ethyl acetate	rCC	1.515		1.515	0.000	5	6
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.093	0.000	4	8
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.094	0.000	4	10
HF+	hydrogen fluoride cation	rHF	1.014		1.015	0.000	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.531	0.000	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.098	0.001	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.510	0.001	2	3
C2H2	Acetylene	rC#C	1.203		1.204	0.001	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.225	0.001	1	2
C3H8	Propane	rCH	1.096		1.097	0.001	1	4
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.092	0.001	2	5
CH3CH2CHO	Propanal	rCC	1.523		1.525	0.002	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.087	0.002	1	2
C3H6	Cyclopropane	rCH	1.083		1.085	0.002	1	4
B2H6	Diborane	rBH	1.320		1.322	0.002	1	3
C2H2	Acetylene	rCH	1.063		1.066	0.003	1	3
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.478	0.003	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.614	0.003	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.162	0.003	1	2
C4H8O2	Ethyl acetate	rCC	1.508		1.511	0.003	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.118	0.003	3	10
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.102	0.003	2	6
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.095	0.004	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.118	0.004	1	4
PN	Phosphorus mononitride	rP#N	1.491		1.495	0.004	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.096	0.004	3	6
CH2CHF	Ethene, fluoro-	rCH	1.082		1.086	0.004	1	4
CH2CO	Ketene	rC=O	1.162		1.166	0.004	2	3
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.415	0.004	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.133	0.004	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.539	0.004	1	2
CH3CCH	propyne	rCH	1.060		1.065	0.005	3	4
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.120	0.005	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.758	0.005	1	2
C3H6	Cyclopropane	rCC	1.501		1.506	0.005	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.091	0.005	2	5
CH4	Methane	rCH	1.087	±0.001	1.092	0.005	1	2
C3H4	cyclopropene	rCH	1.088		1.093	0.005	1	6
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.558	0.005	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.082	0.005	1	3
CH3Br	methyl bromide	rCH	1.082	±0.001	1.088	0.005	1	3
H2O	Water	rOH	0.958	±0.000	0.964	0.006	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.098	0.006	1	3
O2	Oxygen diatomic	rO=O	1.208		1.214	0.007	1	2
CH3CH2OH	Ethanol	rCH	1.088		1.095	0.007	1	5
OCSe	Carbonyl selenide	rC=Se	1.709		1.716	0.007	1	3
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.923	0.007	1	2
C3H4	cyclopropene	rCH	1.072		1.079	0.007	2	4
SiH4	Silane	rSiH	1.480	±0.000	1.486	0.007	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.095	0.007	4	6
C4H8O2	Ethyl acetate	rC=O	1.203		1.210	0.007	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.084	0.007	2	5
SiH3Cl	chlorosilane	rSiH	1.475		1.482	0.007	1	3
OH-	hydroxide anion	rOH	0.964		0.971	0.007	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.092	0.007	2	4
C2H2O2	Ethanedial	rCC	1.526		1.534	0.008	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.282	0.008	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.352	0.008	2	3
SiH3F	monofluorosilane	rSiH	1.476		1.484	0.008	1	3
OH	Hydroxyl radical	rOH	0.970		0.978	0.008	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.660	0.008	1	2
HS-	mercapto anion	rSH	1.343		1.352	0.009	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.704	0.009	1	3
CF	Fluoromethylidyne	rCF	1.276		1.286	0.010	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.746	0.010	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.103	0.010	1	3
BO	boron monoxide	rB=O	1.205		1.215	0.010	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.425	0.011	1	2
PH	phosphorus monohydride	rPH	1.422		1.433	0.011	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.326	0.011	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.433	0.011	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.536	0.011	1	3
C2H3	vinyl	rCH	1.085		1.096	0.011	2	4
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.096	0.012	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.474	0.012	1	2
CH	Methylidyne	rCH	1.120		1.132	0.012	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.461	0.013	1	2
C4H8O2	Ethyl acetate	rCO	1.345		1.358	0.013	2	3
H2Se	Hydrogen selenide	rSeH	1.460		1.473	0.013	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.595	0.013	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.690	0.013	1	2
GeO	Germanium monoxide	rOGe	1.625		1.638	0.013	1	2
BrO	Bromine monoxide	rOBr	1.718		1.731	0.014	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.474	0.014	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.438	0.014	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.525	0.015	1	2
PS	phosphorus sulfide	rP=S	1.900		1.915	0.015	1	2
CH3CH2OH	Ethanol	rCH	1.086		1.101	0.015	2	8
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.623	0.016	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.477	0.016	1	4
PO	Phosphorus monoxide	rP=O	1.476		1.493	0.017	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.628	0.017	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.528	0.018	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.715	0.018	1	3
SiH	Silylidyne	rSiH	1.520		1.538	0.018	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.369	0.018	1	4
LiF	lithium fluoride	rLiF	1.564	±0.000	1.583	0.019	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.277	0.019	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.659	0.020	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.949	0.020	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.787	0.020	1	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.348	0.020	1	3
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.536	0.021	1	3
C3O2	Carbon suboxide	rC=O	1.146		1.167	0.021	2	4
SSO	Disulfur monoxide	rS=O	1.456		1.478	0.021	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.617	0.022	1	2
GeH	germylidene	rGeH	1.588		1.610	0.022	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.782	0.023	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.878	0.023	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.623	0.023	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.601	0.024	1	5
As4	Arsenic tetramer	rAsAs	2.435		2.459	0.024	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.652	0.024	1	2
SO	Sulfur monoxide	rS=O	1.481		1.506	0.025	1	2
S2	Sulfur diatomic	rS=S	1.889		1.914	0.025	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.756	0.025	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.276	0.025	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.077	0.026	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.047	0.026	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.951	0.026	1	4
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.692	0.027	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.911	0.027	2	3
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.184	0.027	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.773	0.028	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.563	0.029	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.608	0.029	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.804	0.029	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.964	0.030	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.685	0.031	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.922	0.031	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.621	0.031	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.199	0.033	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.095	0.034	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.205	0.034	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.172	0.036	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.321	0.040	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.135	0.040	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.107	0.040	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.585	0.040	1	4
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.204	0.041	1	2
HNO3	Nitric acid	rNO	1.406		1.448	0.042	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.690	0.044	1	2
MgH	magnesium monohydride	rMgH	1.730		1.775	0.046	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.110	0.051	1	3
AlBr	Aluminum monobromide	rAlBr	2.295		2.347	0.052	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.411	0.058	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.781	0.067	1	3
C4H8O2	Ethyl acetate	rCO	1.448		1.515	0.067	5	6
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.612	0.082	1	2
NaLi	lithium sodium	rLiNa	2.889		2.974	0.085	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.188	0.107	1	2

185 molecules.