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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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 B2PLYP=FULLultrafine/Def2TZVPP

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.090	-0.440	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.986	-0.092	1	2
C2H2O2	Ethanedial	rCH	1.132		1.102	-0.030	1	3
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.570	-0.026	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.092	-0.025	1	5
C4H8O2	Ethyl acetate	rCH	1.105		1.083	-0.022	1	7
LiOH	lithium hydroxide	rOH	0.969		0.949	-0.020	1	3
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.309	-0.020	1	4
B2H6	Diborane	rBH	1.200		1.183	-0.017	1	5
CH3CH2CHO	Propanal	rCH	1.103		1.087	-0.016	1	6
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.306	-0.015	1	2
CH2NH	Methanimine	rCH	1.103		1.090	-0.013	1	3
HS+	sulfur monohydride cation	rSH	1.374		1.362	-0.013	1	2
C8H8	cubane	rCH	1.097		1.085	-0.012	1	9
F2	Fluorine diatomic	rFF	1.412		1.400	-0.012	1	2
B2H6	Diborane	rBH	1.320		1.308	-0.012	1	3
CH3CH2CHO	Propanal	rCH	1.105		1.094	-0.011	2	8
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.465	-0.010	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.462	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.087	-0.009	1	5
CH3CH2CHO	Propanal	rCH	1.115		1.106	-0.009	3	10
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.284	-0.008	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.526	-0.008	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.008	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.082	-0.008	1	3
CH3CHO	Acetaldehyde	rCH	1.114		1.106	-0.008	1	4
CH3NH2	methyl amine	rNH	1.018	±0.001	1.010	-0.008	2	6
CH3CCH	propyne	rCH	1.096		1.088	-0.008	1	5
LiNH2	lithium amide	rLiN	1.736	±0.003	1.728	-0.008	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.007	-0.007	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.783	-0.007	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.518	-0.007	1	3
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.246	-0.007	1	2
CH2CO	Ketene	rCH	1.083		1.076	-0.007	1	4
C2H2O2	Ethanedial	rCC	1.526		1.519	-0.007	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.092	-0.006	2	6
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.085	-0.006	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.503	-0.006	2	3
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.087	-0.006	4	8
C4H8O2	Ethyl acetate	rCC	1.515		1.509	-0.006	5	6
CH2CHCH2CH3	1-Butene	rCC	1.536		1.530	-0.006	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.576	-0.006	1	2
C4H8O2	Ethyl acetate	rCC	1.508		1.502	-0.006	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.526	-0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.089	-0.005	4	10
HI+	Hydrogen iodide cation	rHI	1.632	±0.000	1.627	-0.005	1	2
C3H8	Propane	rCH	1.096		1.091	-0.005	1	4
CH3CHS	Thioacetaldehyde	rCH	1.090		1.085	-0.005	2	5
SiH4	Silane	rSiH	1.480	±0.000	1.475	-0.005	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.471	-0.005	1	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.086	-0.005	2	5
HI	Hydrogen iodide	rHI	1.609	±0.000	1.604	-0.005	1	2
C3H6	Cyclopropane	rCH	1.083		1.078	-0.005	1	4
SiH3Cl	chlorosilane	rSiH	1.475		1.470	-0.005	1	3
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.081	-0.004	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.095	-0.004	2	6
ICN	Cyanogen iodide	rCI	1.992	±0.000	1.988	-0.004	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.519	-0.004	1	2
HOI	Hypoiodous acid	rOI	1.994	±0.000	1.991	-0.003	1	2
TeH	Telluryl radical	rHTe	1.656	±0.000	1.653	-0.003	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.079	-0.003	1	4
H2CS	Thioformaldehyde	rC=S	1.611		1.608	-0.003	1	2
C3H4	cyclopropene	rCH	1.088		1.085	-0.003	1	6
C2H2	Acetylene	rCH	1.063		1.060	-0.003	1	3
CH3I	methyl iodide	rCH	1.084	±0.003	1.081	-0.003	1	3
HOI	Hypoiodous acid	rOH	0.967	±0.008	0.964	-0.003	1	3
H2Te	Hydrogen Telluride	rHTe	1.651	±0.000	1.649	-0.003	1	2
CH	Methylidyne	rCH	1.120		1.117	-0.003	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.222	-0.002	1	2
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.409	-0.002	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.152	-0.002	1	2
IO	Iodine monoxide	rIO	1.868	±0.004	1.866	-0.002	1	2
C2H5I	Ethyl iodide	rHC	1.093		1.091	-0.002	2	6
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.090	-0.002	3	6
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.091	-0.001	1	3
CH4	Methane	rCH	1.087	±0.001	1.086	-0.001	1	2
CF	Fluoromethylidyne	rCF	1.276		1.275	-0.001	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.158	-0.001	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.328	-0.001	1	2
PH	phosphorus monohydride	rPH	1.422		1.421	-0.001	1	2
C2H2	Acetylene	rC#C	1.203		1.202	-0.001	1	2
BrO	Bromine monoxide	rOBr	1.718		1.717	-0.001	1	2
HS-	mercapto anion	rSH	1.343		1.342	-0.001	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.085	-0.001	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.082	-0.001	1	3
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.752	-0.001	1	2
SbH3	Stibine	rSbH	1.700	±0.000	1.699	-0.001	1	2
NO+	nitric oxide cation	rN=O	1.066		1.065	-0.001	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.020	-0.001	1	2
CH3CCH	propyne	rCH	1.060		1.060	0.000	3	4
C2H2+	acetylene cation	rCH	1.077	±0.005	1.076	0.000	1	3
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.647	0.000	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.697	0.000	1	3
CH3CHS	Thioacetaldehyde	rCH	1.089		1.089	0.000	1	4
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.115	0.000	1	2
CN	Cyano radical	rC#N	1.172		1.172	0.000	1	2
CH2CO	Ketene	rC=O	1.162		1.162	0.000	2	3
C3H4	cyclopropene	rCH	1.072		1.072	0.000	2	4
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.275	0.000	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.553	0.000	1	2
OH	Hydroxyl radical	rOH	0.970		0.970	0.000	1	2
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.086	0.001	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.078	0.001	2	5
N2	Nitrogen diatomic	rN#N	1.098		1.098	0.001	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.089	0.001	4	6
ICN	Cyanogen iodide	rC#N	1.160	±0.000	1.161	0.001	2	3
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.461	0.001	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.316	0.001	1	2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.656	0.001	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.461	0.001	1	2
SiH	Silylidyne	rSiH	1.520		1.521	0.001	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.095	0.002	1	3
C3H6	Cyclopropane	rCC	1.501		1.503	0.002	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.451	0.002	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.417	0.002	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.464	0.002	1	4
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.779	0.002	1	4
LiI	Lithium Iodide	rLiI	2.392	±0.000	2.394	0.002	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.919	0.003	1	2
MgH	magnesium monohydride	rMgH	1.730		1.732	0.003	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.087	0.003	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.304	0.003	1	2
BO	boron monoxide	rB=O	1.205		1.207	0.003	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.945	0.003	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.712	0.003	1	3
C2H3	vinyl	rCH	1.085		1.088	0.003	2	4
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.614	0.003	1	2
C4H8O2	Ethyl acetate	rC=O	1.203		1.207	0.004	2	4
LiF	lithium fluoride	rLiF	1.564	±0.000	1.568	0.004	1	2
HNO3	Nitric acid	rNO	1.406		1.410	0.004	1	2
C4H8O2	Ethyl acetate	rCO	1.345		1.349	0.004	2	3
PS	phosphorus sulfide	rP=S	1.900		1.904	0.004	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.497	0.004	2	3
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.426	0.005	1	2
CH3I	methyl iodide	rCI	2.136	±0.002	2.141	0.005	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.440	0.005	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.516	0.005	1	2
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.162	0.005	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.605	0.006	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.773	0.006	1	4
PF5	Phosphorus pentafluoride	rFP	1.577		1.583	0.006	1	5
SiI4	silicon tetraiodide	rSiI	2.432	±0.005	2.438	0.006	1	2
O2	Oxygen diatomic	rO=O	1.208		1.214	0.006	1	2
GeH	germylidene	rGeH	1.588		1.594	0.006	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.702	0.007	1	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.469	0.007	1	2
CI4	tetraiodomethane	rCI	2.157	±0.010	2.164	0.007	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.498	0.007	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.602	0.007	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.636	0.008	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.359	0.008	1	4
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.684	0.008	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.178	0.008	1	2
IF	Iodine monofluoride	rFI	1.910		1.918	0.008	1	2
ICl	Iodine monochloride	rClI	2.321	±0.000	2.329	0.008	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.933	0.008	1	4
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.337	0.008	1	3
SiH3Cl	chlorosilane	rSiCl	2.051		2.059	0.008	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.433	0.009	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.864	0.009	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.768	0.009	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.939	0.010	1	2
I2	Iodine diatomic	rII	2.665		2.676	0.010	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.520	0.010	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.589	0.010	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.544	0.010	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.945	0.011	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.526	0.012	1	3
TeO	Tellurium monoxide	rO=Te	1.825		1.837	0.012	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.443	0.012	1	2
SO	Sulfur monoxide	rS=O	1.481		1.493	0.012	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.468	0.012	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.904	0.012	1	2
S2	Sulfur diatomic	rS=S	1.889		1.902	0.013	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.271	0.013	1	2
IBr	Iodine monobromide	rBrI	2.469	±0.000	2.482	0.013	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.659	0.013	1	2
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.079	0.013	1	4
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.668	0.013	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.075	0.013	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.558	0.013	1	4
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.653	0.014	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.621	0.014	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.899	0.014	2	3
NaLi	lithium sodium	rLiNa	2.889		2.904	0.015	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.605	0.015	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.151	0.015	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.288	0.016	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.748	0.017	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.260	0.017	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.164	0.018	2	4
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.792	0.018	1	2
GeO	Germanium monoxide	rOGe	1.625		1.643	0.018	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.299	0.018	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.763	0.018	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.184	0.018	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.085	0.018	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.115	0.019	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.078	0.019	1	3
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.184	0.020	1	2
AlI	Aluminum monoiodide	rAlI	2.537	±0.000	2.557	0.020	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.273	0.022	1	2
XeF4	Xenon tetrafluoride	rFXe	1.935	±0.000	1.958	0.023	1	2
XeF2	Xenon difluoride	rFXe	1.974	±0.000	1.999	0.024	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.109	0.028	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.622	0.028	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.381	0.028	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.323	0.028	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.559	0.029	1	2
CaO	Calcium monoxide	rOCa	1.822		1.857	0.035	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.509	0.061	5	6
C4H10O	Methyl propyl ether	rCH	1.099		1.409	0.310	1	2

213 molecules.