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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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/6-311+G(3df,2p)

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.092	-0.438	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.992	-0.085	1	2
Si2	Silicon diatomic	rSiSi	2.246		2.164	-0.082	1	2
C2H2O2	Ethanedial	rCH	1.132		1.102	-0.030	1	3
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.304	-0.025	1	4
LiOH	lithium hydroxide	rOH	0.969		0.947	-0.022	1	3
HNO3	Nitric acid	rNO	1.406		1.384	-0.022	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.095	-0.022	1	5
C5H6	Propellane	rCC	1.596	±0.005	1.576	-0.020	2	5
F2	Fluorine diatomic	rFF	1.412		1.394	-0.018	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.578	-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	-0.018	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.278	-0.014	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.090	-0.013	1	6
B2H6	Diborane	rBH	1.200		1.187	-0.013	1	5
HS+	sulfur monohydride cation	rSH	1.374		1.362	-0.012	1	2
CH2NH	Methanimine	rCH	1.103		1.091	-0.012	1	3
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.962	-0.011	1	2
C5H6	Propellane	rCC	1.525	±0.002	1.514	-0.011	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.687	-0.011	1	3
OCSe	Carbonyl selenide	rC=O	1.159		1.150	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.096	-0.009	2	8
CH3CH2CHO	Propanal	rCH	1.115		1.107	-0.008	3	10
O2	Oxygen diatomic	rO=O	1.208		1.199	-0.008	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.463	-0.008	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.769	-0.008	1	4
CH3CHO	Acetaldehyde	rCH	1.114		1.107	-0.007	1	4
PS	phosphorus sulfide	rP=S	1.900		1.893	-0.007	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.012	-0.006	2	6
B2H6	Diborane	rBH	1.320		1.314	-0.006	1	3
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.601	-0.006	1	2
CH3CCH	propyne	rCH	1.096		1.090	-0.006	1	5
CH3CH2CHO	Propanal	rCH	1.096		1.090	-0.006	1	5
H2CSe	Selenoformaldehyde	rHC	1.090		1.085	-0.006	1	3
CH2CO	Ketene	rCH	1.083		1.077	-0.006	1	4
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.520	-0.005	1	3
CN	Cyano radical	rC#N	1.172		1.167	-0.005	1	2
CF	Fluoromethylidyne	rCF	1.276		1.271	-0.005	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.093	-0.005	2	6
NO+	nitric oxide cation	rN=O	1.066		1.061	-0.004	1	2
N3	azide radical	rNN	1.181		1.177	-0.004	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.340	-0.004	2	3
CH2CHCH2CH3	1-Butene	rCC	1.536		1.532	-0.004	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.248	-0.004	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.471	-0.004	1	2
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.087	-0.004	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.528	-0.003	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.150	-0.003	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.636	-0.003	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.488	-0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.090	-0.003	4	8
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.091	-0.003	4	10
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.643	-0.003	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.454	-0.003	1	2
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.079	-0.003	2	5
CH3CHS	Thioacetaldehyde	rCH	1.090		1.088	-0.002	2	5
C2H2O2	Ethanedial	rCC	1.526		1.524	-0.002	1	2
C3H8	Propane	rCH	1.096		1.094	-0.002	1	4
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.551	-0.002	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.265	-0.002	1	2
CH2CO	Ketene	rC=O	1.162		1.160	-0.002	2	3
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.940	-0.002	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.422	-0.002	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.327	-0.002	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.460	-0.002	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.083	-0.002	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.155	-0.002	1	2
C3H6	Cyclopropane	rCH	1.083		1.081	-0.002	1	4
HCl+	hydrogen chloride cation	rHCl	1.315		1.313	-0.002	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.915	-0.002	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.508	-0.001	2	3
SiH3F	monofluorosilane	rSiH	1.476		1.475	-0.001	1	3
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.533	-0.001	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.522	-0.001	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.883	-0.001	2	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.081	-0.001	1	4
OH	Hydroxyl radical	rOH	0.970		0.969	-0.001	1	2
SO	Sulfur monoxide	rS=O	1.481		1.480	-0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.957	-0.001	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.114	-0.001	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.474	-0.001	1	3
C3H4	cyclopropene	rCH	1.088		1.087	-0.001	1	6
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.224	0.000	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.611	0.000	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.307	0.000	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.275	0.000	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.329	0.000	1	3
CH	Methylidyne	rCH	1.120		1.120	0.000	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.128	0.000	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.767	0.000	1	4
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.351	0.000	1	4
BO	boron monoxide	rB=O	1.205		1.205	0.001	1	2
C2H2	Acetylene	rCH	1.063		1.064	0.001	1	3
H2	Hydrogen diatomic	rHH	0.741		0.742	0.001	1	2
C2H2	Acetylene	rC#C	1.203		1.204	0.001	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.648	0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.424	0.001	1	2
CH4	Methane	rCH	1.087	±0.001	1.088	0.001	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.893	0.001	1	2
HS-	mercapto anion	rSH	1.343		1.345	0.001	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.094	0.002	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.088	0.002	2	5
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.547	0.002	1	4
PO	Phosphorus monoxide	rP=O	1.476		1.477	0.002	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.091	0.002	1	4
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.423	0.002	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.084	0.002	1	3
C3H4	cyclopropene	rCH	1.072		1.074	0.002	2	4
C2H2+	acetylene cation	rCH	1.077	±0.005	1.079	0.002	1	3
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.756	0.003	1	2
CH3CCH	propyne	rCH	1.060		1.063	0.003	3	4
CH3NH2	methyl amine	rCH	1.093	±0.000	1.096	0.003	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.080	0.003	2	5
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.632	0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.091	0.003	4	6
HBr+	hydrogen bromide cation	rHBr	1.448		1.452	0.004	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.929	0.004	1	4
SiH	Silylidyne	rSiH	1.520		1.524	0.004	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.085	0.004	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
C3H6	Cyclopropane	rCC	1.501		1.505	0.004	1	2
S2	Sulfur diatomic	rS=S	1.889		1.894	0.004	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.466	0.004	1	4
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.514	0.005	1	2
C2H3	vinyl	rCH	1.085		1.090	0.005	2	4
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.089	0.005	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.436	0.005	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.064	0.005	1	3
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.861	0.006	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.421	0.006	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.940	0.006	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.264	0.006	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.765	0.006	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.467	0.007	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.659	0.007	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.607	0.007	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.058	0.007	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.937	0.008	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.619	0.008	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.588	0.008	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.502	0.009	2	3
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.704	0.009	1	3
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.176	0.010	1	2
Cl2	Chlorine diatomic	rClCl	1.988		1.997	0.010	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.445	0.010	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.146	0.010	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.686	0.010	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.072	0.010	1	2
BrO	Bromine monoxide	rOBr	1.718		1.729	0.011	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.157	0.011	2	4
SiH3F	monofluorosilane	rSiF	1.595		1.606	0.011	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.523	0.012	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.749	0.013	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.723	0.014	1	3
MgH	magnesium monohydride	rMgH	1.730		1.744	0.014	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.596	0.015	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.296	0.015	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.082	0.015	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.610	0.015	1	2
GeH	germylidene	rGeH	1.588		1.604	0.016	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.606	0.016	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.259	0.016	1	2
C3H5	Allyl radical	rCH	1.069		1.085	0.016	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.113	0.017	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.039	0.019	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.674	0.020	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.184	0.021	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.585	0.021	1	2
GeO	Germanium monoxide	rOGe	1.625		1.647	0.023	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.318	0.023	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.537	0.023	1	3
CFCl	chlorofluoromethylene	rCCl	1.714		1.737	0.023	1	3
C3O2	Carbon suboxide	rC=C	1.251		1.274	0.023	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.325	0.024	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.198	0.028	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.815	0.040	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.398	0.045	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.644	0.050	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.584	0.054	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.789	0.059	1	2
NaLi	lithium sodium	rLiNa	2.889		2.955	0.066	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.811	0.066	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.405	0.306	1	2

185 molecules.