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
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XII	Geometries
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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 HF/daug-cc-pVDZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.983	-0.094	1	2
F2	Fluorine diatomic	rFF	1.412		1.338	-0.074	1	2
HNO3	Nitric acid	rNO	1.406		1.333	-0.073	1	2
O2	Oxygen diatomic	rO=O	1.208		1.162	-0.045	1	2
C2H2O2	Ethanedial	rCH	1.132		1.098	-0.034	1	3
OCSe	Carbonyl selenide	rC=O	1.159		1.125	-0.034	1	2
HF+	hydrogen fluoride cation	rHF	1.014		0.983	-0.032	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.123	-0.031	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.577	-0.030	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.947	-0.026	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.465	-0.026	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.615	-0.025	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.675	-0.022	1	3
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.094	-0.021	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.084	-0.021	1	7
SO+	sulfur monoxide cation	rO=S	1.424		1.403	-0.021	1	2
CH2CO	Ketene	rC=O	1.162		1.141	-0.021	2	3
N2	Nitrogen diatomic	rN#N	1.098		1.078	-0.020	1	2
C4H8O2	Ethyl acetate	rCO	1.345		1.327	-0.018	2	3
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.148	-0.018	1	2
GeO	Germanium monoxide	rOGe	1.625		1.607	-0.018	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.235	-0.018	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.111	-0.018	1	2
OH-	hydroxide anion	rOH	0.964		0.947	-0.017	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.742	-0.017	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.900	-0.017	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.737	-0.016	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.002	-0.016	2	6
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.660	-0.016	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.456	-0.015	1	2
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.396	-0.015	1	2
OH	Hydroxyl radical	rOH	0.970		0.955	-0.015	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.088	-0.015	1	6
H2O	Water	rOH	0.958	±0.000	0.943	-0.015	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.521	-0.014	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.462	-0.013	1	2
CH2NH	Methanimine	rCH	1.103		1.090	-0.013	1	3
C4H8O2	Ethyl acetate	rC=O	1.203		1.190	-0.013	2	4
CH3CH2CHO	Propanal	rCH	1.115		1.103	-0.012	3	10
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.246	-0.012	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.212	-0.012	1	2
C8H8	cubane	rCH	1.097		1.085	-0.012	1	9
CH3CHO	Acetaldehyde	rCH	1.114		1.103	-0.011	1	4
CH3CH2CHO	Propanal	rCH	1.105		1.094	-0.011	2	8
C2H2	Acetylene	rC#C	1.203		1.192	-0.010	1	2
CN	Cyano radical	rC#N	1.172		1.162	-0.010	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.137	-0.009	2	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.320	-0.009	1	3
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.082	-0.009	1	2
CH3CH2OH	Ethanol	rCH	1.098		1.090	-0.008	1	6
B2H6	Diborane	rBH	1.200		1.192	-0.008	1	5
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.545	-0.008	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.284	-0.008	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.083	-0.007	1	3
CH3CCH	propyne	rCH	1.096		1.089	-0.007	1	5
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.344	-0.007	1	4
CH2CO	Ketene	rCH	1.083		1.076	-0.007	1	4
As4	Arsenic tetramer	rAsAs	2.435		2.428	-0.007	1	2
CF	Fluoromethylidyne	rCF	1.276		1.269	-0.007	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.604	-0.007	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.090	-0.006	1	5
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.085	-0.006	2	5
HBr+	hydrogen bromide cation	rHBr	1.448		1.443	-0.006	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.519	-0.006	1	3
C2H2O2	Ethanedial	rCC	1.526		1.521	-0.005	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.093	-0.005	2	6
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.080	-0.005	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.094	-0.005	2	6
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.339	-0.005	2	3
CH3CHS	Thioacetaldehyde	rCH	1.090		1.085	-0.005	2	5
CH2CHF	Ethene, fluoro-	rCH	1.082		1.078	-0.004	1	4
CH	Methylidyne	rCH	1.120		1.116	-0.004	1	2
C3H8	Propane	rCH	1.096		1.092	-0.004	1	4
C4H8O2	Ethyl acetate	rCC	1.508		1.505	-0.003	1	2
C3H6	Cyclopropane	rCH	1.083		1.080	-0.003	1	4
SSO	Disulfur monoxide	rS=O	1.456		1.454	-0.003	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.507	-0.002	2	3
SSO	Disulfur monoxide	rS=S	1.884		1.882	-0.002	2	3
SO	Sulfur monoxide	rS=O	1.481		1.479	-0.002	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.412	-0.002	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.458	-0.002	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.087	-0.002	1	4
C4H8O2	Ethyl acetate	rCC	1.515		1.513	-0.002	5	6
C2H2	Acetylene	rCH	1.063		1.062	-0.001	1	3
Cl2+	chlorine diatomic cation	rClCl	1.892		1.890	-0.001	1	2
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.092	0.000	3	6
C3H4	cyclopropene	rCH	1.088		1.088	0.000	1	6
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.695	0.000	1	3
C2H2+	acetylene cation	rCH	1.077	±0.005	1.077	0.000	1	3
CH3CH2CHO	Propanal	rCC	1.523		1.523	0.000	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.086	0.000	2	5
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.510	0.000	1	2
C3H4	cyclopropene	rCH	1.072		1.073	0.001	2	4
CH3CCH	propyne	rCH	1.060		1.061	0.001	3	4
CH3Br	methyl bromide	rCH	1.082	±0.001	1.083	0.001	1	3
S2	Sulfur diatomic	rS=S	1.889		1.890	0.001	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.085	0.001	1	2
C3H6	Cyclopropane	rCC	1.501		1.502	0.001	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.316	0.001	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.087	0.002	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.079	0.002	2	5
CH3NH2	methyl amine	rCH	1.093	±0.000	1.095	0.002	1	3
CH4	Methane	rCH	1.087	±0.001	1.089	0.002	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.513	0.003	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.478	0.003	1	3
CH3CH2OH	Ethanol	rCH	1.088		1.091	0.003	1	5
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.277	0.003	1	2
PH	phosphorus monohydride	rPH	1.422		1.425	0.003	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.479	0.003	1	3
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.933	0.004	1	2
GeH	germylidene	rGeH	1.588		1.592	0.004	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.779	0.005	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.931	0.006	1	4
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.163	0.006	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.486	0.006	1	2
H2	Hydrogen diatomic	rHH	0.741		0.748	0.007	1	2
CH3CH2OH	Ethanol	rCH	1.086		1.093	0.007	2	8
B2H6	Diborane	rBH	1.320		1.327	0.007	1	3
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.739	0.008	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.469	0.008	1	4
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.654	0.008	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.585	0.008	1	5
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.553	0.008	1	4
SiH	Silylidyne	rSiH	1.520		1.528	0.008	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.776	0.009	1	4
BF	Boron monofluoride	rBF	1.267	±0.000	1.275	0.009	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.755	0.010	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.574	0.010	1	2
MgH	magnesium monohydride	rMgH	1.730		1.740	0.011	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.748	0.012	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.659	0.012	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.548	0.014	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.529	0.015	1	3
SF	Monosulfur monofluoride	rSF	1.599		1.614	0.015	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.949	0.015	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.151	0.015	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.671	0.017	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.298	0.017	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.007	0.019	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.272	0.021	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.617	0.022	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.732	0.023	1	3
PF2	Phosphorus difluoride	rPF	1.579		1.606	0.027	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.624	0.028	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.624	0.030	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.620	0.030	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.885	0.031	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.129	0.033	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.061	0.040	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.095	0.044	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.221	0.050	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.216	0.052	1	2
BrO	Bromine monoxide	rOBr	1.718		1.772	0.054	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.123	0.056	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.119	0.058	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.592	0.062	1	2
PS	phosphorus sulfide	rP=S	1.900		1.964	0.064	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.513	0.065	5	6
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.424	0.071	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.371	0.077	1	2

160 molecules.