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
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IX	Feedback
X	Older CCCBDB versions
XII	Geometries
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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 TPSSh/cc-pVQZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	1.979	-0.098	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.246	-0.055	1	2
C2H2O2	Ethanedial	rCH	1.132		1.106	-0.026	1	3
CH3CH2CH2CH3	Butane	rCH	1.117		1.095	-0.022	1	5
C4H8O2	Ethyl acetate	rCH	1.105		1.086	-0.019	1	7
CaO	Calcium monoxide	rOCa	1.822		1.804	-0.018	1	2
LiOH	lithium hydroxide	rOH	0.969		0.952	-0.017	1	3
B2H6	Diborane	rBH	1.200		1.186	-0.014	1	5
CH3CH2CHO	Propanal	rCH	1.103		1.090	-0.013	1	6
HeH+	Helium hydride cation	rHHe	0.790		0.777	-0.013	1	2
F2	Fluorine diatomic	rFF	1.412		1.400	-0.012	1	2
ClO	Monochlorine monoxide	rClO	1.596	±0.001	1.585	-0.011	1	2
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.486	-0.011	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.726	-0.010	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.470	-0.010	1	2
C8H8	cubane	rCH	1.097		1.088	-0.009	1	9
CH2NH	Methanimine	rCH	1.103		1.095	-0.008	1	3
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.313	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.097	-0.008	2	8
LiOH	lithium hydroxide	rLiO	1.582		1.574	-0.008	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.245	-0.007	1	2
CH3CH2OH	Ethanol	rCH	1.098		1.091	-0.007	1	6
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.587	-0.007	1	2
CN	Cyano radical	rC#N	1.172		1.166	-0.006	1	2
NO+	nitric oxide cation	rN=O	1.066		1.060	-0.006	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.090	-0.006	1	5
CH3NH2	methyl amine	rCN	1.471	±0.003	1.466	-0.005	1	2
B2H6	Diborane	rBH	1.320		1.315	-0.005	1	3
HS+	sulfur monohydride cation	rSH	1.374		1.370	-0.005	1	2
H2CSe	Selenoformaldehyde	rHC	1.090		1.086	-0.005	1	3
C2H2	Acetylene	rC#C	1.203		1.198	-0.005	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.431	-0.004	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.149	-0.004	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.969	-0.004	1	2
CH3CCH	propyne	rCH	1.096		1.092	-0.004	1	5
NH4+	ammonium cation	rHN	1.029	±0.000	1.025	-0.004	1	2
H2CSe	Selenoformaldehyde	rC=Se	1.753		1.749	-0.004	1	2
AsH	Arsenic monohydride	rAsH	1.535	±0.001	1.531	-0.004	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.111	-0.004	3	10
N3	azide radical	rNN	1.181		1.177	-0.004	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.014	-0.004	2	6
CH2CO	Ketene	rCH	1.083		1.079	-0.004	1	4
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.471	-0.004	1	2
N2	Nitrogen diatomic	rN#N	1.098		1.094	-0.003	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.111	-0.003	1	4
PN	Phosphorus mononitride	rP#N	1.491		1.488	-0.003	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.156	-0.003	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.090	-0.003	4	8
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.091	-0.003	4	10
C2H2O2	Ethanedial	rCC	1.526		1.523	-0.003	1	2
HSiCl	Chlorosilylene	rSiH	1.525	±0.005	1.522	-0.003	1	3
NSe	Nitrogen monoselenide	rN=Se	1.652		1.649	-0.003	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.507	-0.002	2	3
CH3CHClCH3	Propane, 2-chloro-	rCH	1.091		1.089	-0.002	2	5
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.113	-0.002	1	2
C4H8O2	Ethyl acetate	rCC	1.515		1.513	-0.002	5	6
CHF3	Methane, trifluoro-	rCH	1.091	±0.014	1.089	-0.002	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.222	-0.002	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.083	-0.002	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.609	-0.002	1	2
C3H8	Propane	rCH	1.096		1.094	-0.002	1	4
C4H8O2	Ethyl acetate	rCC	1.508		1.506	-0.002	1	2
HF+	hydrogen fluoride cation	rHF	1.014		1.013	-0.001	1	2
C3H6	Cyclopropane	rCH	1.083		1.082	-0.001	1	4
CH3CH2CH2CH3	Butane	rCC	1.531		1.530	-0.001	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.563	-0.001	1	2
CH3OCH3	Dimethyl ether	rCH	1.099	±0.001	1.098	-0.001	2	6
CH3CH2CHO	Propanal	rCC	1.523		1.523	0.000	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.292	0.000	1	2
C2H2	Acetylene	rCH	1.063		1.063	0.000	1	3
SiH4	Silane	rSiH	1.480	±0.000	1.480	0.000	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.128	0.000	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.553	0.000	1	2
CH2CO	Ketene	rC=O	1.162		1.162	0.000	2	3
CH2CHF	Ethene, fluoro-	rCH	1.082		1.082	0.000	1	4
O2	Oxygen diatomic	rO=O	1.208		1.208	0.000	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.476	0.001	1	3
SiH3F	monofluorosilane	rSiH	1.476		1.477	0.001	1	3
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.498	0.001	1	2
C3H4	cyclopropene	rCH	1.088		1.089	0.001	1	6
CH3CHClCH3	Propane, 2-chloro-	rCH	1.092		1.094	0.002	3	6
OCSe	Carbonyl selenide	rC=Se	1.709		1.711	0.002	1	3
BO	boron monoxide	rB=O	1.205		1.206	0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.094	0.002	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.088	0.002	2	5
CH3OCH3	Dimethyl ether	rCO	1.411	±0.001	1.413	0.002	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.084	0.002	1	3
CH4	Methane	rCH	1.087	±0.001	1.089	0.002	1	2
CH3CCH	propyne	rCH	1.060		1.062	0.002	3	4
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.697	0.002	1	3
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.347	0.003	2	3
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.024	0.003	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.080	0.003	1	3
C3H6	Cyclopropane	rCC	1.501		1.504	0.003	1	2
PS	phosphorus sulfide	rP=S	1.900		1.903	0.003	1	2
CSe	Carbon monoselenide	rC=Se	1.676	±0.000	1.680	0.003	1	2
C3H4	cyclopropene	rCH	1.072		1.075	0.003	2	4
CH3CH2OH	Ethanol	rCH	1.088		1.092	0.004	1	5
CH3OCH3	Dimethyl ether	rCH	1.085	±0.001	1.089	0.004	2	4
CH2CHF	Ethene, fluoro-	rCH	1.077		1.081	0.004	2	5
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.092	0.004	4	6
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.611	0.004	1	2
GeO	Germanium monoxide	rOGe	1.625		1.629	0.004	1	2
PH	phosphorus monohydride	rPH	1.422		1.427	0.004	1	2
C4H8O2	Ethyl acetate	rC=O	1.203		1.208	0.005	2	4
SO+	sulfur monoxide cation	rO=S	1.424		1.429	0.005	1	2
CF	Fluoromethylidyne	rCF	1.276		1.281	0.005	1	2
H2O	Water	rOH	0.958	±0.000	0.963	0.005	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.703	0.005	1	3
SeCl2	Selenium Dichloride	rClSe	2.157	±0.003	2.162	0.005	1	2
HS-	mercapto anion	rSH	1.343		1.349	0.005	1	2
CH	Methylidyne	rCH	1.120		1.125	0.005	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.645	0.006	1	2
CH3NH2	methyl amine	rCH	1.093	±0.000	1.099	0.006	1	3
C4H8O2	Ethyl acetate	rCO	1.345		1.351	0.006	2	3
CH2F2	Methane, difluoro-	rCH	1.084	±0.003	1.090	0.006	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.466	0.006	1	2
OH-	hydroxide anion	rOH	0.964		0.971	0.007	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.467	0.007	1	2
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.923	0.007	1	2
SiH	Silylidyne	rSiH	1.520		1.527	0.007	1	2
C2H3	vinyl	rCH	1.085		1.092	0.007	2	4
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.421	0.007	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.281	0.007	1	2
OH	Hydroxyl radical	rOH	0.970		0.977	0.007	1	2
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.469	0.007	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.766	0.007	1	2
Se2	Selenium diatomic	rSe=Se	2.166	±0.001	2.173	0.007	1	2
BrO	Bromine monoxide	rOBr	1.718		1.725	0.008	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.512	0.008	1	2
SiO	Silicon monoxide	rSiO	1.510	±0.000	1.517	0.008	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.456	0.008	1	2
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.020	0.008	1	2
AlNC	Aluminum isocyanide	rAlN	1.855	±0.005	1.863	0.008	1	2
PO	Phosphorus monoxide	rP=O	1.476		1.484	0.008	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.179	0.009	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.470	0.009	1	4
SiS	silicon monosulfide	rSiS	1.929	±0.000	1.938	0.009	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.430	0.009	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.520	0.009	1	2
GeH	germylidene	rGeH	1.588		1.598	0.010	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.325	0.010	1	2
CH3CH2OH	Ethanol	rCH	1.086		1.097	0.011	2	8
SF	Monosulfur monofluoride	rSF	1.599		1.611	0.012	1	2
S2	Sulfur diatomic	rS=S	1.889		1.901	0.012	1	2
HNO3	Nitric acid	rNO	1.406		1.418	0.012	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.293	0.012	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.779	0.012	1	4
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.938	0.013	1	4
GaF	Gallium monofluoride	rFGa	1.774	±0.000	1.787	0.013	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.149	0.013	1	2
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.271	0.013	1	2
CH2F2	Methane, difluoro-	rCF	1.351	±0.001	1.364	0.013	1	4
SSO	Disulfur monoxide	rS=O	1.456		1.469	0.013	1	2
GeF	Germanium monofluoride	rFGe	1.745		1.758	0.013	1	2
PF5	Phosphorus pentafluoride	rFP	1.577		1.590	0.013	1	5
GeH3F	monofluorogermane	rGeF	1.731	±0.000	1.744	0.013	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.064	0.013	1	2
SiH3F	monofluorosilane	rSiF	1.595		1.608	0.013	1	2
CHF3	Methane, trifluoro-	rCF	1.328	±0.003	1.342	0.013	1	3
SO	Sulfur monoxide	rS=O	1.481		1.495	0.014	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.642	0.014	1	2
MgH	magnesium monohydride	rMgH	1.730		1.743	0.014	1	2
SSO	Disulfur monoxide	rS=S	1.884		1.899	0.015	2	3
SiF	silicon monofluoride	rSiF	1.604		1.620	0.015	1	2
GeH3F	monofluorogermane	rGeH	1.515	±0.000	1.530	0.015	1	3
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.626	0.015	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.950	0.016	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.162	0.016	2	4
Cl2+	chlorine diatomic cation	rClCl	1.892		1.908	0.016	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.596	0.017	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.682	0.017	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.051	0.018	1	4
AlF	Aluminum monofluoride	rAlF	1.654	±0.000	1.672	0.018	1	2
SiCl	Clorosilylidyne	rSiCl	2.061	±0.000	2.080	0.018	1	2
PF5	Phosphorus pentafluoride	rPF	1.534		1.553	0.019	1	2
SiF2	Silicon difluoride	rFSi	1.590	±0.000	1.610	0.020	1	2
GeCl	Germanium monochloride	rClGe	2.164	±0.000	2.184	0.020	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.272	0.021	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.117	0.022	1	2
HSiCl	Chlorosilylene	rSiCl	2.067	±0.003	2.089	0.022	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.669	0.023	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.084	0.025	1	3
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.570	0.025	1	4
GaBr	Gallium monobromide	rGaBr	2.352	±0.000	2.380	0.027	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.323	0.028	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.569	0.039	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.128	0.047	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.761	0.047	1	3
C4H8O2	Ethyl acetate	rCO	1.448		1.513	0.065	5	6
NaLi	lithium sodium	rLiNa	2.889		2.956	0.067	1	2

191 molecules.