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 QCISD(T)/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		1.094	-0.436	5	13
CaO	Calcium monoxide	rOCa	1.822		1.686	-0.137	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.002	-0.075	1	2
C2H2O2	Ethanedial	rCH	1.132		1.105	-0.027	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.097	-0.020	1	5
LiOH	lithium hydroxide	rOH	0.969		0.949	-0.020	1	3
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.580	-0.016	1	2
HF+	hydrogen fluoride cation	rHF	1.014		0.999	-0.016	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.016	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.280	-0.012	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.091	-0.012	1	6
B2H6	Diborane	rBH	1.200		1.188	-0.012	1	5
CH2NH	Methanimine	rCH	1.103		1.093	-0.010	1	3
HS+	sulfur monohydride cation	rSH	1.374		1.366	-0.009	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.098	-0.007	2	8
CH3CH2CHO	Propanal	rCH	1.115		1.109	-0.006	3	10
B2H6	Diborane	rBH	1.320		1.315	-0.005	1	3
CH3CHO	Acetaldehyde	rCH	1.114		1.109	-0.005	1	4
CH3CH2CHO	Propanal	rCH	1.096		1.091	-0.005	1	5
C5H6	Propellane	rCC	1.525	±0.002	1.521	-0.004	1	2
C5H6	Propellane	rCC	1.596	±0.005	1.592	-0.004	2	5
CH3CCH	propyne	rCH	1.096		1.092	-0.004	1	5
H2CSe	Selenoformaldehyde	rHC	1.090		1.086	-0.004	1	3
CH3NH2	methyl amine	rNH	1.018	±0.001	1.014	-0.004	2	6
CH2CO	Ketene	rCH	1.083		1.079	-0.004	1	4
CH3NH2	methyl amine	rCN	1.471	±0.003	1.468	-0.003	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.522	-0.003	1	3
CH3CH2SH	ethanethiol	rCH	1.095		1.092	-0.003	1	4
C2H2O2	Ethanedial	rCC	1.526		1.523	-0.003	1	2
HNO3	Nitric acid	rNO	1.406		1.404	-0.002	1	2
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.089	-0.002	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.775	-0.002	1	4
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.342	-0.002	2	3
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.473	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.091	-0.002	4	8
CH2CHCH2CH3	1-Butene	rCC	1.536		1.534	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.093	-0.001	4	10
CH3CH2CH2CH3	Butane	rCC	1.531		1.530	-0.001	1	2
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.081	-0.001	2	5
CF	Fluoromethylidyne	rCF	1.276		1.276	-0.001	1	2
C3H6	Cyclopropane	rCH	1.083		1.083	0.000	1	4
OCSe	Carbonyl selenide	rC=O	1.159		1.159	0.000	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.476	0.000	1	3
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.085	0.000	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.917	0.000	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.267	0.000	1	2
CH3CH2SH	ethanethiol	rCH	1.092		1.092	0.000	1	5
HCl+	hydrogen chloride cation	rHCl	1.315		1.315	0.000	1	2
H2	Hydrogen diatomic	rHH	0.741		0.742	0.001	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.476	0.001	1	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.083	0.001	1	4
CH3CH2CHO	Propanal	rCC	1.509		1.510	0.001	2	3
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.254	0.001	1	2
CH3CH2SH	ethanethiol	rCH	1.090		1.091	0.001	2	7
CH3CH2CHO	Propanal	rCC	1.523		1.524	0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
CH	Methylidyne	rCH	1.120		1.122	0.002	1	2
OH	Hydroxyl radical	rOH	0.970		0.971	0.002	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.536	0.002	1	2
O2	Oxygen diatomic	rO=O	1.208		1.209	0.002	1	2
C2H2	Acetylene	rCH	1.063		1.065	0.002	1	3
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.277	0.002	1	2
NO+	nitric oxide cation	rN=O	1.066		1.068	0.002	1	2
CH4	Methane	rCH	1.087	±0.001	1.089	0.002	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.310	0.003	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.157	0.003	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.701	0.003	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.089	0.003	2	5
N3	azide radical	rNN	1.181		1.184	0.003	1	2
CH2CO	Ketene	rC=O	1.162		1.165	0.003	2	3
F2	Fluorine diatomic	rFF	1.412		1.415	0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.095	0.003	1	3
CH3Br	methyl bromide	rCH	1.082	±0.001	1.086	0.004	1	3
PH	phosphorus monohydride	rPH	1.422		1.426	0.004	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.425	0.004	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.085	0.004	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.081	0.004	1	3
HS-	mercapto anion	rSH	1.343		1.348	0.004	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.097	0.004	1	3
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.355	0.004	1	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.333	0.005	1	3
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.772	0.005	1	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.082	0.005	2	5
CH3CCH	propyne	rCH	1.060		1.065	0.005	3	4
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.162	0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.093	0.005	4	6
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.229	0.005	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.652	0.006	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.121	0.006	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.134	0.006	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.466	0.006	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.467	0.006	1	4
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.559	0.006	1	2
SiH	Silylidyne	rSiH	1.520		1.526	0.006	1	2
BO	boron monoxide	rB=O	1.205		1.211	0.006	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.104	0.006	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.455	0.006	1	2
C2H3	vinyl	rCH	1.085		1.092	0.007	2	4
PS	phosphorus sulfide	rP=S	1.900		1.907	0.007	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.091	0.007	1	2
C2H2	Acetylene	rC#C	1.203		1.210	0.007	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.618	0.007	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.423	0.008	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.499	0.008	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.648	0.009	1	2
C3H6	Cyclopropane	rCC	1.501		1.510	0.009	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.864	0.009	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.060	0.009	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.469	0.009	1	2
SO	Sulfur monoxide	rS=O	1.481		1.490	0.009	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.934	0.009	1	4
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.617	0.010	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.466	0.010	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.555	0.010	1	4
CH2CHCH2CH3	1-Butene	rCC	1.493		1.503	0.010	2	3
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.764	0.011	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.487	0.011	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.945	0.011	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.442	0.011	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.255	0.012	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.522	0.013	1	2
BrO	Bromine monoxide	rOBr	1.718		1.731	0.013	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.665	0.013	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.075	0.013	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.593	0.014	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.723	0.014	1	3
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.643	0.015	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.614	0.015	1	2
MgH	magnesium monohydride	rMgH	1.730		1.745	0.015	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.710	0.015	1	3
SiH3F	monofluorosilane	rSiF	1.595		1.609	0.015	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.610	0.015	1	2
Si2	Silicon diatomic	rSiSi	2.246		2.261	0.015	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.751	0.015	1	2
S2	Sulfur diatomic	rS=S	1.889		1.905	0.016	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.900	0.016	2	3
LiOH	lithium hydroxide	rLiO	1.582		1.598	0.017	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.084	0.017	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.777	0.018	1	2
C3H5	Allyl radical	rCH	1.069		1.087	0.018	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.006	0.018	1	2
GeH	germylidene	rGeH	1.588		1.606	0.018	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.165	0.019	2	4
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.155	0.019	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.695	0.019	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.948	0.019	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.292	0.020	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.610	0.020	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.041	0.021	1	2
CuH	Copper monohydride	rCuH	1.463		1.484	0.021	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.188	0.022	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.304	0.023	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.678	0.023	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.458	0.023	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.187	0.024	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.588	0.024	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.539	0.024	1	3
C3O2	Carbon suboxide	rC=C	1.251		1.278	0.027	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.200	0.029	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.744	0.030	1	3
GeO	Germanium monoxide	rOGe	1.625		1.655	0.031	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.819	0.044	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.399	0.047	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.588	0.058	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.794	0.063	1	2
NaLi	lithium sodium	rLiNa	2.889		2.954	0.065	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.816	0.071	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.411	0.312	1	2

170 molecules.