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)/Def2TZVPP

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	2.003	-0.075	1	2
CaO	Calcium monoxide	rOCa	1.822		1.763	-0.060	1	2
C2H2O2	Ethanedial	rCH	1.132		1.103	-0.029	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.096	-0.021	1	5
LiOH	lithium hydroxide	rOH	0.969		0.948	-0.021	1	3
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.303	-0.017	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.277	-0.015	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.090	-0.013	1	6
HF+	hydrogen fluoride cation	rHF	1.014		1.002	-0.012	1	2
B2H6	Diborane	rBH	1.200		1.189	-0.011	1	5
HS+	sulfur monohydride cation	rSH	1.374		1.364	-0.011	1	2
CH2NH	Methanimine	rCH	1.103		1.092	-0.011	1	3
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.586	-0.010	1	2
HI+	Hydrogen iodide cation	rHI	1.632	±0.000	1.623	-0.009	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.466	-0.009	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.096	-0.009	2	8
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.527	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.108	-0.007	3	10
HI	Hydrogen iodide	rHI	1.609	±0.000	1.602	-0.007	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.107	-0.007	1	4
H2CSe	Selenoformaldehyde	rHC	1.090		1.085	-0.006	1	3
B2H6	Diborane	rBH	1.320		1.315	-0.005	1	3
CH3CH2CHO	Propanal	rCH	1.096		1.091	-0.005	1	5
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.520	-0.005	1	3
HOI	Hypoiodous acid	rOI	1.994	±0.000	1.989	-0.005	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.013	-0.005	2	6
CH3CCH	propyne	rCH	1.096		1.091	-0.005	1	5
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.339	-0.005	2	3
TeH	Telluryl radical	rHTe	1.656	±0.000	1.651	-0.005	1	2
H2Te	Hydrogen Telluride	rHTe	1.651	±0.000	1.647	-0.005	1	2
CH2CO	Ketene	rCH	1.083		1.078	-0.005	1	4
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.086	-0.005	1	2
C2H2O2	Ethanedial	rCC	1.526		1.522	-0.004	1	2
HOI	Hypoiodous acid	rOH	0.967	±0.008	0.964	-0.003	1	3
SbH3	Stibine	rSbH	1.700	±0.000	1.697	-0.003	1	2
CH3NH2	methyl amine	rCN	1.471	±0.003	1.468	-0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.090	-0.003	4	8
CH2CHCH2CH3	1-Butene	rCC	1.536		1.534	-0.002	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.529	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.092	-0.002	4	10
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.940	-0.002	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.419	-0.002	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.083	-0.002	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.313	-0.002	1	2
CI4	tetraiodomethane	rCI	2.157	±0.010	2.155	-0.002	1	2
CH3I	methyl iodide	rCI	2.136	±0.002	2.134	-0.001	1	2
SiH3F	monofluorosilane	rSiH	1.476		1.475	-0.001	1	3
HBr+	hydrogen bromide cation	rHBr	1.448		1.447	-0.001	1	2
C3H4	cyclopropene	rCH	1.088		1.087	-0.001	1	6
SiH3Cl	chlorosilane	rSiH	1.475		1.474	-0.001	1	3
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.274	-0.001	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.435	0.000	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.080	0.000	1	2
CH2CHF	Ethene, fluoro-	rCH	1.082		1.082	0.000	1	4
CH3I	methyl iodide	rCH	1.084	±0.003	1.084	0.000	1	3
CH3CH2CHO	Propanal	rCC	1.509		1.509	0.000	2	3
SiI4	silicon tetraiodide	rSiI	2.432	±0.005	2.433	0.001	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.917	0.001	1	2
ICN	Cyanogen iodide	rCI	1.992	±0.000	1.993	0.001	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.778	0.001	1	4
C2H5I	Ethyl iodide	rHC	1.093		1.094	0.001	2	6
OCSe	Carbonyl selenide	rC=O	1.159		1.160	0.001	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.415	0.001	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.524	0.001	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.647	0.001	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.461	0.001	1	2
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
HS-	mercapto anion	rSH	1.343		1.345	0.001	1	2
TeO	Tellurium monoxide	rO=Te	1.825		1.827	0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.094	0.002	1	3
CH	Methylidyne	rCH	1.120		1.122	0.002	1	2
IF	Iodine monofluoride	rFI	1.910		1.911	0.002	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.255	0.002	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.085	0.002	1	3
PH	phosphorus monohydride	rPH	1.422		1.425	0.002	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.088	0.002	2	5
C2H2+	acetylene cation	rCH	1.077	±0.005	1.080	0.003	1	3
NO+	nitric oxide cation	rN=O	1.066		1.069	0.003	1	2
HNO3	Nitric acid	rNO	1.406		1.409	0.003	1	2
C3H4	cyclopropene	rCH	1.072		1.075	0.003	2	4
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.160	0.003	1	2
CH3CCH	propyne	rCH	1.060		1.064	0.004	3	4
GeH	germylidene	rGeH	1.588		1.592	0.004	1	2
SiH	Silylidyne	rSiH	1.520		1.524	0.004	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.097	0.004	1	3
CH2CHF	Ethene, fluoro-	rCH	1.077		1.081	0.004	2	5
CF	Fluoromethylidyne	rCF	1.276		1.280	0.004	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.092	0.004	4	6
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.158	0.004	1	2
GeBr4	Germanium tetrabromide	rGeBr	2.272	±0.001	2.276	0.004	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.702	0.004	1	3
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.930	0.005	1	4
CH2CO	Ketene	rC=O	1.162		1.167	0.005	2	3
AsH3	Arsine	rAsH	1.511	±0.000	1.516	0.005	1	2
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.089	0.005	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.558	0.005	1	2
F2	Fluorine diatomic	rFF	1.412		1.417	0.005	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.467	0.005	1	4
C2H3	vinyl	rCH	1.085		1.091	0.006	2	4
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.357	0.006	1	4
SiH3F	monofluorosilane	rSiF	1.595		1.601	0.006	1	2
ICN	Cyanogen iodide	rC#N	1.160	±0.000	1.167	0.006	2	3
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.335	0.006	1	3
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.940	0.006	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.606	0.007	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.743	0.007	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.618	0.007	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.774	0.007	1	4
BF	Boron monofluoride	rBF	1.267	±0.000	1.274	0.007	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.586	0.007	1	2
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.782	0.007	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.760	0.007	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.766	0.007	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.123	0.007	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.552	0.007	1	4
LiOH	lithium hydroxide	rLiO	1.582		1.589	0.008	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.863	0.008	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.059	0.008	1	2
AlI	Aluminum monoiodide	rAlI	2.537	±0.000	2.546	0.008	1	2
XeF4	Xenon tetrafluoride	rFXe	1.935	±0.000	1.943	0.009	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.648	0.009	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.754	0.009	1	2
MgH	magnesium monohydride	rMgH	1.730		1.739	0.009	1	2
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.740	0.009	1	2
ICl	Iodine monochloride	rClI	2.321	±0.000	2.331	0.010	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.719	0.010	1	3
CH2CHCH2CH3	1-Butene	rCC	1.493		1.503	0.010	2	3
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.617	0.010	1	2
BO	boron monoxide	rB=O	1.205		1.215	0.011	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.639	0.011	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.525	0.011	1	3
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.706	0.011	1	3
XeF2	Xenon difluoride	rFXe	1.974	±0.000	1.985	0.011	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.601	0.011	1	2
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.666	0.011	1	2
PN	Phosphorus mononitride	rP#N	1.491		1.503	0.012	1	2
SO	Sulfur monoxide	rS=O	1.481		1.493	0.012	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.443	0.012	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.074	0.012	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.176	0.012	1	2
SSO	Disulfur monoxide	rS=O	1.456		1.469	0.013	1	2
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.365	0.013	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.179	0.013	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.544	0.014	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.524	0.014	1	2
BrO	Bromine monoxide	rOBr	1.718		1.732	0.014	1	2
PS	phosphorus sulfide	rP=S	1.900		1.915	0.015	1	2
IBr	Iodine monobromide	rBrI	2.469	±0.000	2.485	0.016	1	2
GeO	Germanium monoxide	rOGe	1.625		1.640	0.016	1	2
I2	Iodine diatomic	rII	2.665		2.681	0.016	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.083	0.016	1	2
S2	Sulfur diatomic	rS=S	1.889		1.905	0.016	1	2
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.082	0.016	1	4
LiF	lithium fluoride	rLiF	1.564	±0.000	1.580	0.016	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.693	0.017	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.038	0.017	1	2
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.947	0.017	1	2
IO	Iodine monoxide	rIO	1.868	±0.004	1.885	0.018	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.903	0.018	2	3
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.155	0.019	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.300	0.019	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.166	0.020	2	4
LiI	Lithium Iodide	rLiI	2.392	±0.000	2.416	0.024	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.197	0.027	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.279	0.028	1	2
NaLi	lithium sodium	rLiNa	2.889		2.965	0.076	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.326	0.084	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.413	0.314	1	2

172 molecules.