National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
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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 CCSD/6-31+G**

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.093	-0.437	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.999	-0.079	1	2
C2H2O2	Ethanedial	rCH	1.132		1.100	-0.032	1	3
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.270	-0.022	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.358	-0.016	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.460	-0.015	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.520	-0.015	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.090	-0.013	1	6
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.513	-0.012	1	3
CH2NH	Methanimine	rCH	1.103		1.091	-0.012	1	3
CH3CH2CHO	Propanal	rCH	1.115		1.105	-0.010	3	10
CH3CHO	Acetaldehyde	rCH	1.114		1.104	-0.010	1	4
CH3CH2CHO	Propanal	rCH	1.105		1.096	-0.009	2	8
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.336	-0.008	2	3
HNO3	Nitric acid	rNO	1.406		1.398	-0.008	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.307	-0.008	1	2
CH2	Methylene	rCH	1.085		1.078	-0.007	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.084	-0.007	1	3
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.322	-0.007	1	4
H2Se	Hydrogen selenide	rSeH	1.460		1.454	-0.006	1	2
C2H2O2	Ethanedial	rCC	1.526		1.520	-0.006	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.470	-0.006	1	3
CH3CCH	propyne	rCH	1.096		1.090	-0.006	1	5
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.085	-0.006	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.009	-0.006	1	2
CH2CO	Ketene	rCH	1.083		1.077	-0.006	1	4
CH3CH2CHO	Propanal	rCH	1.096		1.090	-0.006	1	5
SiH3Cl	chlorosilane	rSiH	1.475		1.470	-0.005	1	3
CH3NH2	methyl amine	rNH	1.018	±0.001	1.013	-0.005	2	6
CH3NH2	methyl amine	rCN	1.471	±0.003	1.466	-0.005	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.093	-0.005	2	6
SiH4	Silane	rSiH	1.480	±0.000	1.475	-0.005	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.749	-0.004	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.672	-0.004	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.969	-0.004	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.444	-0.004	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.705	-0.004	1	3
BH	Boron monohydride	rBH	1.232		1.229	-0.003	1	2
D2	Deuterium diatomic	rDD	0.742		0.738	-0.003	1	2
H2	Hydrogen diatomic	rHH	0.741		0.738	-0.003	1	2
BH3	boron trihydride	rBH	1.190		1.187	-0.003	1	2
CH2CHCH2CH3	1-Butene	rCC	1.536		1.533	-0.003	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.508	-0.002	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.412	-0.002	1	2
CH3CHS	Thioacetaldehyde	rCH	1.090		1.088	-0.002	2	5
CH2CHF	Ethene, fluoro-	rCH	1.082		1.080	-0.002	1	4
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.273	-0.001	1	2
DCl	Hydrochloric acid-d	rDCl	1.275	±0.000	1.273	-0.001	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.084	-0.001	1	2
C3H6	Cyclopropane	rCH	1.083		1.082	-0.001	1	4
C3H4	cyclopropene	rCH	1.088		1.088	-0.000	1	6
HS	Mercapto radical	rSH	1.341		1.341	0.000	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.695	0.000	1	3
DS	Mercapto-d	rSD	1.341		1.341	0.000	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.462	0.000	1	4
CH3CHS	Thioacetaldehyde	rCH	1.089		1.089	0.000	1	4
CH3CH2CHO	Propanal	rCC	1.509		1.510	0.001	2	3
CH	Methylidyne	rCH	1.120		1.121	0.001	1	2
CH2O2	Dioxirane	rCH	1.090	±0.002	1.091	0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.423	0.001	1	2
SiH	Silylidyne	rSiH	1.520		1.521	0.001	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.524	0.001	1	2
CH4	Methane	rCH	1.087	±0.001	1.088	0.001	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.554	0.001	1	2
BeH	beryllium monohydride	rBeH	1.343		1.344	0.001	1	2
BeH2	beryllium dihydride	rBeH	1.326	±0.000	1.328	0.001	1	2
C2H2	Acetylene	rCH	1.063		1.064	0.001	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.088	0.002	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.084	0.002	1	3
GeH	germylidene	rGeH	1.588		1.590	0.002	1	2
AlH	aluminum monohydride	rAlH	1.648		1.650	0.003	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.079	0.003	1	3
C3H4	cyclopropene	rCH	1.072		1.075	0.003	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.080	0.003	2	5
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.087	0.003	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.945	0.003	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.096	0.003	1	3
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.333	0.004	1	2
C2H3	vinyl	rCH	1.085		1.089	0.004	2	4
CH3CCH	propyne	rCH	1.060		1.064	0.004	3	4
H2O	Water	rOH	0.958	±0.000	0.962	0.004	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.975	0.004	1	3
CS	carbon monosulfide	rC#S	1.535		1.539	0.005	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.163	0.005	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.257	0.005	1	2
NH	Imidogen	rNH	1.036		1.041	0.005	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.652	0.005	1	2
DO	Hydroxyl-d	rDO	0.970		0.976	0.006	1	2
OH	Hydroxyl radical	rOH	0.970		0.976	0.006	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.774	0.007	1	4
DF	Hydrofluoric acid-d	rDF	0.917	±0.000	0.924	0.007	1	2
C3H6	Cyclopropane	rCC	1.501		1.508	0.007	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.924	0.007	1	2
CH2O2	Dioxirane	rCO	1.388	±0.004	1.395	0.008	1	4
CH2O2	Dioxirane	rOO	1.516	±0.003	1.523	0.008	4	5
H2CS	Thioformaldehyde	rC=S	1.611		1.619	0.009	1	2
CN	Cyano radical	rC#N	1.172		1.181	0.009	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.939	0.010	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.234	0.010	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.501	0.010	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.618	0.011	1	2
C2H2	Acetylene	rC#C	1.203		1.214	0.012	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.505	0.012	2	3
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.127	0.012	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.166	0.012	1	2
CH2CO	Ketene	rC=O	1.162		1.175	0.013	2	3
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.653	0.014	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.142	0.014	1	2
Si2	Silicon diatomic	rSiSi	2.246		2.260	0.014	1	2
O2	Oxygen diatomic	rO=O	1.208		1.221	0.014	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.449	0.014	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.065	0.014	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.529	0.014	1	3
PS	phosphorus sulfide	rP=S	1.900		1.915	0.015	1	2
HO2	Hydroperoxy radical	rOO	1.331		1.346	0.016	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.075	0.016	1	3
C3H5	Allyl radical	rCH	1.069		1.085	0.016	1	2
MgH	magnesium monohydride	rMgH	1.730		1.746	0.016	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.324	0.017	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.942	0.017	1	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.346	0.018	1	3
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.528	0.019	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.080	0.019	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.481	0.019	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.370	0.020	1	4
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.115	0.020	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.088	0.021	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.178	0.021	1	2
CF	Fluoromethylidyne	rCF	1.276		1.297	0.021	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.288	0.021	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.956	0.022	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.280	0.022	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.906	0.022	2	3
F2	Fluorine diatomic	rFF	1.412		1.434	0.022	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.721	0.023	1	3
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.187	0.024	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.448	0.024	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.601	0.024	1	5
C3O2	Carbon suboxide	rC=O	1.146		1.171	0.025	2	4
CaOH	Calcium monohydroxide	rOH	0.930	±0.007	0.955	0.025	2	3
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.191	0.025	1	2
S2	Sulfur diatomic	rS=S	1.889		1.915	0.026	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.321	0.026	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.557	0.027	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.623	0.027	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.381	0.028	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.883	0.028	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.279	0.028	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.486	0.029	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.302	0.030	1	2
SO	Sulfur monoxide	rS=O	1.481		1.511	0.030	1	2
GeO	Germanium monoxide	rOGe	1.625		1.656	0.032	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.678	0.032	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.567	0.033	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.769	0.033	1	2
CuF	Copper monofluoride	rCuF	1.745	±0.000	1.779	0.034	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.629	0.034	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.793	0.034	1	2
NaH	sodium hydride	rNaH	1.887	±0.000	1.921	0.035	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.927	0.035	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.631	0.037	1	2
CuCl	Copper monochloride	rCuCl	2.051	±0.000	2.088	0.037	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.602	0.038	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.693	0.039	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.631	0.041	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.669	0.041	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.062	0.041	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.586	0.041	1	4
PF2	Phosphorus difluoride	rPF	1.579		1.621	0.042	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.643	0.043	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.180	0.044	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.032	0.044	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.655	0.044	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.819	0.044	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.329	0.048	1	2
BrO	Bromine monoxide	rOBr	1.718		1.766	0.049	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.783	0.052	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.801	0.056	1	2
NaLi	lithium sodium	rLiNa	2.889		2.956	0.067	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.434	0.133	1	2
CaOH	Calcium monohydroxide	rOCa	1.976	±0.004	2.113	0.137	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.731	0.137	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.418	0.319	1	2

183 molecules.