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 M06-2X/daug-cc-pVTZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
Na2	Sodium diatomic	rNaNa	3.079		2.955	-0.123	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.976	-0.102	1	2
NaLi	lithium sodium	rLiNa	2.889		2.831	-0.058	1	2
F2	Fluorine diatomic	rFF	1.412		1.365	-0.046	1	2
C2H2O2	Ethanedial	rCH	1.132		1.103	-0.029	1	3
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.568	-0.028	1	2
HNO3	Nitric acid	rNO	1.406		1.380	-0.026	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.084	-0.021	1	7
CN	Cyano radical	rC#N	1.172		1.152	-0.020	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.679	-0.018	1	3
O2	Oxygen diatomic	rO=O	1.208		1.190	-0.018	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.137	-0.017	1	2
B2H6	Diborane	rBH	1.200		1.184	-0.016	1	5
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.592	-0.015	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.088	-0.015	1	6
OCSe	Carbonyl selenide	rC=O	1.159		1.144	-0.014	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.477	-0.014	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.102	-0.013	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.240	-0.013	1	2
C8H8	cubane	rCH	1.097		1.085	-0.012	1	9
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.741	-0.012	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.086	-0.011	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.460	-0.011	1	2
CH2NH	Methanimine	rCH	1.103		1.092	-0.011	1	3
CH3CH2CHO	Propanal	rCH	1.105		1.095	-0.010	2	8
H2CS	Thioformaldehyde	rC=S	1.611		1.601	-0.010	1	2
B2H6	Diborane	rBH	1.320		1.310	-0.010	1	3
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.630	-0.009	1	2
CH3CH2OH	Ethanol	rCH	1.098		1.089	-0.009	1	6
C2H2	Acetylene	rC#C	1.203		1.194	-0.009	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.009	1	2
CF	Fluoromethylidyne	rCF	1.276		1.268	-0.008	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.751	-0.008	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.527	-0.008	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.728	-0.008	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.216	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.107	-0.008	3	10
CH3CH2CHO	Propanal	rCH	1.096		1.088	-0.008	1	5
SO+	sulfur monoxide cation	rO=S	1.424		1.416	-0.008	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.517	-0.008	1	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.545	-0.008	1	2
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.587	-0.008	1	2
CH2CO	Ketene	rC=O	1.162		1.155	-0.007	2	3
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.404	-0.007	1	2
BrO	Bromine monoxide	rOBr	1.718		1.711	-0.007	1	2
CH3CCH	propyne	rCH	1.096		1.089	-0.007	1	5
PS	phosphorus sulfide	rP=S	1.900		1.893	-0.007	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.011	-0.007	2	6
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.251	-0.007	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.107	-0.007	1	4
CO	Carbon monoxide	rC#O	1.128	±0.000	1.121	-0.007	1	2
C4H8O2	Ethyl acetate	rCC	1.508		1.501	-0.007	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.670	-0.007	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.503	-0.006	2	3
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.469	-0.006	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.084	-0.006	1	3
C4H8O2	Ethyl acetate	rCC	1.515		1.509	-0.006	5	6
CH2CO	Ketene	rCH	1.083		1.077	-0.006	1	4
CH3CH2CHO	Propanal	rCC	1.523		1.517	-0.006	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.430	-0.005	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.093	-0.005	2	6
HF+	hydrogen fluoride cation	rHF	1.014		1.010	-0.005	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.262	-0.004	1	2
C3H8	Propane	rCH	1.096		1.092	-0.004	1	4
CH	Methylidyne	rCH	1.120		1.116	-0.004	1	2
CH3CHS	Thioacetaldehyde	rCH	1.090		1.086	-0.004	2	5
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.087	-0.004	2	5
C3H6	Cyclopropane	rCH	1.083		1.079	-0.004	1	4
GeO	Germanium monoxide	rOGe	1.625		1.621	-0.004	1	2
PH	phosphorus monohydride	rPH	1.422		1.419	-0.003	1	2
C2H2O2	Ethanedial	rCC	1.526		1.523	-0.003	1	2
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.088	-0.003	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.082	-0.003	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.154	-0.003	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.096	-0.003	2	6
C4H8O2	Ethyl acetate	rCO	1.345		1.342	-0.003	2	3
SiH3F	monofluorosilane	rSiH	1.476		1.473	-0.003	1	3
H2	Hydrogen diatomic	rHH	0.741		0.739	-0.003	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.472	-0.003	1	3
C3H6	Cyclopropane	rCC	1.501		1.499	-0.002	1	2
SiH4	Silane	rSiH	1.480	±0.000	1.477	-0.002	1	2
C4H8O2	Ethyl acetate	rC=O	1.203		1.201	-0.002	2	4
SSO	Disulfur monoxide	rS=S	1.884		1.882	-0.002	2	3
OH-	hydroxide anion	rOH	0.964		0.962	-0.002	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.342	-0.002	2	3
SiH	Silylidyne	rSiH	1.520		1.518	-0.002	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.645	-0.002	1	2
C3H4	cyclopropene	rCH	1.088		1.086	-0.002	1	6
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.164	-0.002	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.081	-0.001	1	4
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.091	-0.001	3	6
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.509	-0.001	1	2
C2H2	Acetylene	rCH	1.063		1.063	0.000	1	3
CH4	Methane	rCH	1.087	±0.001	1.087	0.000	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.086	0.000	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.083	0.001	1	3
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.930	0.001	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.293	0.001	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.892	0.001	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.090	0.001	1	4
CH3CH2OH	Ethanol	rCH	1.088		1.089	0.001	1	5
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.601	0.002	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.697	0.002	1	3
C3H4	cyclopropene	rCH	1.072		1.074	0.002	2	4
CH3NH2	methyl amine	rCH	1.093	±0.000	1.095	0.002	1	3
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.927	0.002	1	4
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.023	0.002	1	2
OH	Hydroxyl radical	rOH	0.970		0.972	0.002	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.566	0.002	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.079	0.002	1	3
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.087	0.002	2	4
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.353	0.002	1	4
SSO	Disulfur monoxide	rS=O	1.456		1.459	0.002	1	2
CH3CCH	propyne	rCH	1.060		1.063	0.003	3	4
Br2	Bromine diatomic	rBrBr	2.281		2.284	0.003	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.770	0.003	1	4
S2	Sulfur diatomic	rS=S	1.889		1.892	0.003	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.920	0.003	1	2
CH2CHF	Ethene, fluoro-	rCH	1.077		1.080	0.003	2	5
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.332	0.003	1	3
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.139	0.003	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.465	0.004	1	4
SO	Sulfur monoxide	rS=O	1.481		1.485	0.004	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.939	0.005	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.279	0.005	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.089	0.005	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.453	0.005	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.465	0.005	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.582	0.005	1	5
C3O2	Carbon suboxide	rC=O	1.146		1.152	0.006	2	4
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.421	0.006	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.321	0.007	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.717	0.008	1	3
CH3CH2OH	Ethanol	rCH	1.086		1.094	0.008	2	8
GeH	germylidene	rGeH	1.588		1.596	0.008	1	2
Cl2	Chlorine diatomic	rClCl	1.988		1.996	0.009	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.655	0.009	1	2
MgH	magnesium monohydride	rMgH	1.730		1.738	0.009	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.520	0.010	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.180	0.010	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.545	0.011	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.556	0.011	1	4
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.866	0.011	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.743	0.012	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.591	0.012	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.607	0.012	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.758	0.013	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.788	0.013	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.669	0.015	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.066	0.015	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.607	0.016	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.079	0.017	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.116	0.021	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.272	0.021	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.537	0.022	1	3
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.090	0.023	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.192	0.029	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.334	0.039	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.398	0.045	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.575	0.045	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.509	0.061	5	6

162 molecules.