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 MP3/cc-pVTZ

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.565	-0.090	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.402	-0.065	1	2
CN	Cyano radical	rC#N	1.172		1.129	-0.043	1	2
C5H8O	Methyl cyclopropyl ketone	rCH	1.126		1.085	-0.041	3	7
C2H	Ethynyl radical	rC#C	1.217		1.176	-0.040	1	2
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.302	-0.027	1	4
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.581	-0.026	1	2
F2	Fluorine diatomic	rFF	1.412		1.386	-0.026	1	2
LiOH	lithium hydroxide	rOH	0.969		0.944	-0.025	1	3
C5H6	Propellane	rCC	1.596	±0.005	1.571	-0.025	2	5
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.090	-0.025	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.092	-0.025	1	5
NO	Nitric oxide	rN=O	1.154	±0.000	1.131	-0.023	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.083	-0.022	1	7
FO	Oxygen monofluoride	rFO	1.354		1.333	-0.021	1	2
GeO	Germanium monoxide	rOGe	1.625		1.604	-0.021	1	2
NSe	Nitrogen monoselenide	rN=Se	1.652		1.631	-0.021	1	2
SiC	silicon monocarbide	rCSi	1.722		1.701	-0.020	1	2
O2+	diatomic oxygen cation	rOO	1.116		1.096	-0.020	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.693	-0.020	1	4
C5H8	Ethenylcyclopropane	rCH	1.099		1.080	-0.019	1	6
HO2	Hydroperoxy radical	rOO	1.331		1.313	-0.018	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.623	-0.017	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.304	-0.017	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.142	-0.016	1	2
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.459	-0.016	1	2
N3	azide radical	rNN	1.181		1.165	-0.016	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.087	-0.016	1	6
O2	Oxygen diatomic	rO=O	1.208		1.192	-0.016	1	2
BN	boron nitride	rB=N	1.325		1.310	-0.015	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.775	-0.015	1	2
NO+	nitric oxide cation	rN=O	1.066		1.051	-0.015	1	2
B2H6	Diborane	rBH	1.200		1.186	-0.014	1	5
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.959	-0.014	1	2
CH2NH	Methanimine	rCH	1.103		1.089	-0.014	1	3
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.279	-0.013	1	2
C10H8	Azulene	rC:C	1.414		1.402	-0.013	7	9
CH3CH2CHO	Propanal	rCH	1.115		1.103	-0.012	3	10
CH3OC2H5	Ethane, methoxy-	rCO	1.415	±0.005	1.403	-0.012	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.093	-0.012	2	8
CF	Fluoromethylidyne	rCF	1.276		1.264	-0.012	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.468	-0.012	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.103	-0.011	1	4
C5H6	Propellane	rCC	1.525	±0.002	1.514	-0.011	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.364	-0.010	1	2
C2	Carbon diatomic	rC=C	1.243		1.233	-0.010	1	2
C3H6O	2-Propen-1-ol	rCH	1.092	±0.010	1.082	-0.010	2	7
C3H3NO	Oxazole	rCO	1.357	±0.003	1.348	-0.010	1	2
CH2	Methylene	rCH	1.085		1.075	-0.010	1	2
C3H6O	2-Propen-1-ol	rCH	1.091	±0.010	1.081	-0.010	3	9
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.683	-0.010	1	2
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.932	-0.010	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.750	-0.009	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.020	-0.009	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.009	-0.009	2	6
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.727	-0.009	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.412	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.087	-0.009	1	5
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.488	-0.009	1	2
CH3CCH	propyne	rCH	1.096		1.088	-0.008	1	5
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.172	-0.008	1	3
CH2CO	Ketene	rCH	1.083		1.074	-0.008	1	4
CH3NH2	methyl amine	rCN	1.471	±0.003	1.463	-0.008	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.440	-0.008	1	2
CH2CO	Ketene	rC=O	1.162		1.154	-0.008	2	3
C3H6O	2-Propen-1-ol	rCH	1.102	±0.020	1.094	-0.008	1	6
N2	Nitrogen diatomic	rN#N	1.098		1.090	-0.008	1	2
BO	boron monoxide	rB=O	1.205		1.197	-0.008	1	2
B2H6	Diborane	rBH	1.320		1.312	-0.008	1	3
C3H3NO	Oxazole	rCO	1.370	±0.002	1.362	-0.007	1	5
CH3NO	nitrosomethane	rCH	1.094		1.087	-0.007	1	4
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.639	-0.007	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.170	-0.007	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.091	-0.007	2	6
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.688	-0.007	1	3
GeH	germylidene	rGeH	1.588		1.582	-0.006	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.122	-0.006	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.964	-0.006	1	3
H2Se	Hydrogen selenide	rSeH	1.460		1.454	-0.006	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.597	-0.006	1	3
SO+	sulfur monoxide cation	rO=S	1.424		1.418	-0.006	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.547	-0.006	1	2
BF	Boron monofluoride	rBF	1.267	±0.000	1.261	-0.006	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.505	-0.006	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.087	-0.006	4	8
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.075	-0.006	1	2
C4H8O2	Ethyl acetate	rCO	1.345		1.340	-0.005	2	3
C3H8	Propane	rCH	1.096		1.091	-0.005	1	4
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.339	-0.005	2	3
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.080	-0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.089	-0.005	4	10
C4H8O2	Ethyl acetate	rCC	1.508		1.503	-0.005	1	2
CH2CHCH2CH3	1-Butene	rCC	1.536		1.531	-0.005	1	2
C4H8	cyclobutane	rCH	1.093		1.088	-0.005	1	5
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.077	-0.005	2	5
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.661	-0.005	1	2
C3H6	Cyclopropane	rCH	1.083		1.078	-0.005	1	4
CH3CHS	Thioacetaldehyde	rCH	1.090		1.085	-0.005	2	5
C4H8O2	Ethyl acetate	rC=O	1.203		1.198	-0.005	2	4
CH3OC2H5	Ethane, methoxy-	rCH	1.099	±0.007	1.094	-0.005	1	6
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.410	-0.005	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.526	-0.005	1	2
C4H8	cyclobutane	rCH	1.091		1.086	-0.005	1	6
C10H8	Azulene	rC:C	1.398		1.393	-0.005	1	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.457	-0.005	1	2
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.248	-0.004	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.693	-0.004	1	3
CH3OC2H5	Ethane, methoxy-	rCH	1.092	±0.007	1.088	-0.004	4	11
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.254	-0.004	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.592	-0.004	1	3
CH3OC2H5	Ethane, methoxy-	rCH	1.100	±0.003	1.096	-0.004	3	8
CH3CH2CHO	Propanal	rCC	1.509		1.505	-0.004	2	3
C10H8	Azulene	rCH	1.084		1.080	-0.004	4	14
PO	Phosphorus monoxide	rP=O	1.476		1.472	-0.004	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.220	-0.004	1	2
CH3NO	nitrosomethane	rCH	1.092		1.088	-0.004	1	5
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.913	-0.004	1	2
C3H4	cyclopropene	rCH	1.088		1.084	-0.004	1	6
C10H8	Azulene	rCH	1.080		1.076	-0.004	9	17
C3H6O	2-Propen-1-ol	rCH	1.096	±0.030	1.093	-0.003	1	5
C4H8O2	Ethyl acetate	rCC	1.515		1.512	-0.003	5	6
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.326	-0.003	1	2
C2H2	Acetylene	rC#C	1.203		1.200	-0.003	1	2
C3H3NO	Oxazole	rCH	1.075	±0.001	1.072	-0.003	4	7
H2O	Water	rOH	0.958	±0.000	0.955	-0.003	1	2
C10H8	Azulene	rC:C	1.405	±0.001	1.402	-0.003	2	9
As4	Arsenic tetramer	rAsAs	2.435		2.432	-0.003	1	2
OH	Hydroxyl radical	rOH	0.970		0.967	-0.003	1	2
OH-	hydroxide anion	rOH	0.964		0.961	-0.003	1	2
C3H3NO	Oxazole	rCH	1.075	±0.001	1.072	-0.003	2	6
C3H3NO	Oxazole	rCH	1.073	±0.001	1.070	-0.003	5	8
C2H2	Acetylene	rCH	1.063		1.060	-0.003	1	3
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.010	-0.003	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.597	-0.003	1	2
CH3CHS	Thioacetaldehyde	rCH	1.089		1.086	-0.003	1	4
H2CS	Thioformaldehyde	rC=S	1.611		1.608	-0.002	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.521	-0.002	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.734	-0.002	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.923	-0.002	1	4
H2	Hydrogen diatomic	rHH	0.741		0.739	-0.002	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.645	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.090	-0.002	1	3
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.932	-0.002	1	2
C5H8O	Methyl cyclopropyl ketone	rCC	1.510		1.509	-0.001	2	3
CH3CHO	Acetaldehyde	rCH	1.086		1.085	-0.001	2	5
CH4	Methane	rCH	1.087	±0.001	1.086	-0.001	1	2
BH	Boron monohydride	rBH	1.232		1.232	-0.001	1	2
HCl	Hydrogen chloride	rHCl	1.275	±0.000	1.274	-0.001	1	2
C3H4	cyclopropene	rCH	1.072		1.071	-0.001	2	4
ScH	Scandium monohydride	rScH	1.775	±0.000	1.775	-0.001	1	2
CH3CCH	propyne	rCH	1.060		1.059	-0.001	3	4
SiH3Cl	chlorosilane	rSiH	1.475		1.474	-0.001	1	3
CH3OC2H5	Ethane, methoxy-	rCH	1.089	±0.008	1.088	-0.001	4	10
CH3Br	methyl bromide	rCH	1.082	±0.001	1.082	0.000	1	3
SiH4	Silane	rSiH	1.480	±0.000	1.479	0.000	1	2
BF3	Borane, trifluoro-	rBF	1.307		1.307	0.000	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.314	0.000	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.777	0.000	1	4
CH3OC2H5	Ethane, methoxy-	rCH	1.086	±0.010	1.086	0.000	1	5
C2H2+	acetylene cation	rCH	1.077	±0.005	1.077	0.000	1	3
C10H8	Azulene	rCH	1.081		1.081	0.000	1	11
C10H8	Azulene	rCH	1.083		1.083	0.000	5	15
CH3OC2H5	Ethane, methoxy-	rCO	1.407	±0.004	1.407	0.000	2	3
HS	Mercapto radical	rSH	1.341		1.341	0.001	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.089	0.001	4	6
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.629	0.001	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.540	0.001	1	5
CH3NH2	methyl amine	rCH	1.093	±0.000	1.094	0.001	1	3
P2	Phosphorus diatomic	rP#P	1.893		1.894	0.001	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.546	0.001	1	4
C2H3	vinyl	rCH	1.085		1.086	0.001	2	4
HS-	mercapto anion	rSH	1.343		1.345	0.001	1	2
C3H6O	2-Propen-1-ol	rCH	1.078	±0.010	1.079	0.001	3	8
PF2	Phosphorus difluoride	rPF	1.579		1.581	0.001	1	2
C5H8	Ethenylcyclopropane	rCC	1.475		1.476	0.001	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.583	0.002	1	2
PH	phosphorus monohydride	rPH	1.422		1.424	0.002	1	2
BeH	beryllium monohydride	rBeH	1.343		1.345	0.002	1	2
SO	Sulfur monoxide	rS=O	1.481		1.483	0.002	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.711	0.002	1	3
SiH+	silicon monohydride cation	rSiH	1.504		1.507	0.003	1	2
SiH	Silylidyne	rSiH	1.520		1.524	0.004	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.464	0.004	1	2
MgH	magnesium monohydride	rMgH	1.730		1.734	0.004	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.150	0.004	2	4
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.677	0.004	1	2
C3H6	Cyclopropane	rCC	1.501		1.506	0.005	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.772	0.005	1	4
SiH2F2	difluorosilane	rSiH	1.462		1.466	0.005	1	4
SiF	silicon monofluoride	rSiF	1.604		1.610	0.005	1	2
NH2CONH2	Urea	rNH	0.998		1.003	0.005	4	8
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.503	0.006	1	2
LiO	lithium oxide	rLiO	1.688		1.695	0.007	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.538	0.008	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.501	0.008	2	3
LiH	Lithium Hydride	rLiH	1.595	±0.000	1.604	0.009	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.440	0.009	1	2
C10H8	Azulene	rC:C	1.377		1.387	0.010	5	7
C10H8	Azulene	rC:C	1.484		1.494	0.010	7	8
BrO	Bromine monoxide	rOBr	1.718		1.728	0.011	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.275	0.011	1	2
B2	Boron diatomic	rBB	1.590		1.601	0.011	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.107	0.012	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.293	0.012	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.577	0.013	1	2
C2H	Ethynyl radical	rCH	1.047		1.060	0.013	1	3
C3H5	Allyl radical	rCH	1.069		1.082	0.013	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.072	0.013	1	3
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.150	0.014	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.065	0.014	1	2
S2	Sulfur diatomic	rS=S	1.889		1.905	0.016	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.909	0.017	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.051	0.018	1	4
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.040	0.019	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.033	0.021	1	2
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.151	0.021	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.009	0.021	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.273	0.022	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.192	0.022	1	2
C5H8O	Cyclopentanone	rCC	1.504		1.526	0.022	2	3
AlBr	Aluminum monobromide	rAlBr	2.295		2.318	0.023	1	2
SCl	sulfur monochloride	rSCl	1.975		1.999	0.024	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.635	0.025	1	2
PS	phosphorus sulfide	rP=S	1.900		1.927	0.027	1	2
AlC	Aluminum carbide	rC=Al	1.955		1.984	0.029	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.746	0.032	1	3
CaO	Calcium monoxide	rOCa	1.822		1.857	0.035	1	2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.117	0.039	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.403	0.042	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.971	0.045	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.352	0.051	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.512	0.064	5	6
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.667	0.074	1	2
Al2Cl6	Aluminum, di-μ-chlorotetrachlorodi-	rAlCl	2.040	±0.040	2.280	0.240	1	3

234 molecules.