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=FULL/TZVP

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
C4H10O	Methyl propyl ether	rCC	1.530		1.091	-0.439	5	13
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.007	-0.071	1	2
FNO2	Nitryl fluoride	rNF	1.467	±0.015	1.422	-0.045	1	2
CN	Cyano radical	rC#N	1.172		1.129	-0.043	1	2
C5H8O	Methyl cyclopropyl ketone	rCH	1.126		1.086	-0.040	3	7
C2H	Ethynyl radical	rC#C	1.217		1.177	-0.040	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.090	-0.025	1	2
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.304	-0.025	1	4
CH3CH2CH2CH3	Butane	rCH	1.117		1.093	-0.024	1	5
C5H6	Propellane	rCC	1.596	±0.005	1.572	-0.024	2	5
LiOH	lithium hydroxide	rOH	0.969		0.945	-0.024	1	3
NO	Nitric oxide	rN=O	1.154	±0.000	1.130	-0.024	1	2
ScH	Scandium monohydride	rScH	1.775	±0.000	1.755	-0.021	1	2
C4H8O2	Ethyl acetate	rCH	1.105		1.084	-0.021	1	7
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.588	-0.019	1	2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.636	-0.019	1	2
C5H8	Ethenylcyclopropane	rCH	1.099		1.081	-0.018	1	6
O2+	diatomic oxygen cation	rOO	1.116		1.099	-0.017	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.142	-0.017	1	2
BN	boron nitride	rB=N	1.325		1.308	-0.017	1	2
B2H6	Diborane	rBH	1.200		1.184	-0.016	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.459	-0.016	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.305	-0.015	1	2
N3	azide radical	rNN	1.181		1.166	-0.015	1	2
F2	Fluorine diatomic	rFF	1.412		1.397	-0.015	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.088	-0.015	1	6
NSe	Nitrogen monoselenide	rN=Se	1.652		1.637	-0.015	1	2
SiH2Cl2	dichlorosilane	rSiH	1.480	±0.015	1.465	-0.015	1	2
GeO	Germanium monoxide	rOGe	1.625		1.610	-0.015	1	2
FO	Oxygen monofluoride	rFO	1.354		1.340	-0.014	1	2
CH2NH	Methanimine	rCH	1.103		1.089	-0.014	1	3
NO+	nitric oxide cation	rN=O	1.066		1.052	-0.014	1	2
C2	Carbon diatomic	rC=C	1.243		1.229	-0.013	1	2
C10H8	Azulene	rC:C	1.414		1.402	-0.013	7	9
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.961	-0.012	1	2
C5H6	Propellane	rCC	1.525	±0.002	1.513	-0.012	1	2
CH3CH2CHO	Propanal	rCH	1.115		1.103	-0.012	3	10
HO2	Hydroperoxy radical	rOO	1.331		1.319	-0.011	1	2
O2	Oxygen diatomic	rO=O	1.208		1.196	-0.011	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.094	-0.011	2	8
CH3CHO	Acetaldehyde	rCH	1.114		1.103	-0.011	1	4
CH3OC2H5	Ethane, methoxy-	rCO	1.415	±0.005	1.405	-0.010	1	2
CH2	Methylene	rCH	1.085		1.075	-0.010	1	2
B2H6	Diborane	rBH	1.320		1.310	-0.010	1	3
CH3NH2	methyl amine	rCN	1.471	±0.003	1.461	-0.010	1	2
C3H6O	2-Propen-1-ol	rCH	1.092	±0.010	1.083	-0.009	2	7
CF	Fluoromethylidyne	rCF	1.276		1.267	-0.009	1	2
C3H6O	2-Propen-1-ol	rCH	1.091	±0.010	1.082	-0.009	3	9
HS+	sulfur monohydride cation	rSH	1.374		1.366	-0.009	1	2
CN-	cyanide anion	rC#N	1.177	±0.004	1.169	-0.008	1	2
CH3NH2	methyl amine	rNH	1.018	±0.001	1.010	-0.008	2	6
CH2CO	Ketene	rC=O	1.162		1.154	-0.008	2	3
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.284	-0.008	1	2
C3H3NO	Oxazole	rCO	1.357	±0.003	1.349	-0.008	1	2
CH2CO	Ketene	rCH	1.083		1.075	-0.008	1	4
C4H6	Bicyclo[1.1.0]butane	rCC	1.497		1.489	-0.008	1	2
CH3CCH	propyne	rCH	1.096		1.088	-0.008	1	5
HeH+	Helium hydride cation	rHHe	0.790		0.782	-0.008	1	2
HBr+	hydrogen bromide cation	rHBr	1.448		1.441	-0.008	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.088	-0.008	1	5
N2	Nitrogen diatomic	rN#N	1.098		1.090	-0.008	1	2
NH4+	ammonium cation	rHN	1.029	±0.000	1.021	-0.007	1	2
CO	Carbon monoxide	rC#O	1.128	±0.000	1.121	-0.007	1	2
FNO2	Nitryl fluoride	rN=O	1.180	±0.005	1.173	-0.007	1	3
BO	boron monoxide	rB=O	1.205		1.197	-0.007	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.414	-0.007	1	2
C3H6O	2-Propen-1-ol	rCH	1.102	±0.020	1.095	-0.007	1	6
CSe2	Carbon diselenide	rC=Se	1.692	±0.000	1.685	-0.007	1	2
C3H3NO	Oxazole	rCO	1.370	±0.002	1.363	-0.006	1	5
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.246	-0.006	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.092	-0.006	2	6
CH3NO	nitrosomethane	rCH	1.094		1.088	-0.006	1	4
H2Se	Hydrogen selenide	rSeH	1.460		1.454	-0.006	1	2
CH2CHCH2CH3	1-Butene	rCC	1.536		1.530	-0.006	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.634	-0.006	1	2
SiC	silicon monocarbide	rCSi	1.722		1.716	-0.006	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.080	-0.005	1	2
BH	Boron monohydride	rBH	1.232		1.227	-0.005	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.526	-0.005	1	2
C10H8	Azulene	rC:C	1.398		1.393	-0.005	1	3
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.219	-0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.088	-0.005	4	8
C2H2ClF	1-chloro-1-fluoroethylene	rCH	1.082	±0.001	1.077	-0.005	2	5
C3H8	Propane	rCH	1.096		1.091	-0.005	1	4
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.089	-0.005	4	10
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.410	-0.004	1	2
C4H8O2	Ethyl acetate	rC=O	1.203		1.199	-0.004	2	4
C4H8O2	Ethyl acetate	rCC	1.508		1.504	-0.004	1	2
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.325	-0.004	1	2
C10H8	Azulene	rC:C	1.405	±0.001	1.400	-0.004	2	9
CH3CHS	Thioacetaldehyde	rCH	1.090		1.086	-0.004	2	5
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.340	-0.004	2	3
CH3OC2H5	Ethane, methoxy-	rCH	1.099	±0.007	1.095	-0.004	1	6
C4H8	cyclobutane	rCH	1.093		1.090	-0.004	1	5
CH3OC2H5	Ethane, methoxy-	rCH	1.092	±0.007	1.088	-0.004	4	11
BeH	beryllium monohydride	rBeH	1.343		1.339	-0.004	1	2
HO2	Hydroperoxy radical	rOH	0.971		0.967	-0.003	1	3
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.550	-0.003	1	2
SiH3Cl	chlorosilane	rSiH	1.475		1.472	-0.003	1	3
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.692	-0.003	1	3
CH3CH2CHO	Propanal	rCC	1.509		1.506	-0.003	2	3
C4H8O2	Ethyl acetate	rCO	1.345		1.342	-0.003	2	3
CH3NO	nitrosomethane	rCH	1.092		1.089	-0.003	1	5
C4H8O2	Ethyl acetate	rCC	1.515		1.512	-0.003	5	6
CH3OC2H5	Ethane, methoxy-	rCH	1.100	±0.003	1.097	-0.003	3	8
C4H8	cyclobutane	rCH	1.091		1.088	-0.003	1	6
C3H4	cyclopropene	rCH	1.088		1.085	-0.003	1	6
C10H8	Azulene	rCH	1.084		1.081	-0.003	4	14
C3H3NO	Oxazole	rCH	1.075	±0.001	1.073	-0.003	4	7
SiH4	Silane	rSiH	1.480	±0.000	1.477	-0.003	1	2
C10H8	Azulene	rCH	1.080		1.077	-0.003	9	17
C3H3NO	Oxazole	rCH	1.075	±0.001	1.073	-0.002	2	6
CH3CHS	Thioacetaldehyde	rCH	1.089		1.087	-0.002	1	4
CH3CH2CHO	Propanal	rCC	1.523		1.521	-0.002	1	2
C3H6O	2-Propen-1-ol	rCH	1.096	±0.030	1.094	-0.002	1	5
C3H3NO	Oxazole	rCH	1.073	±0.001	1.071	-0.002	5	8
H2	Hydrogen diatomic	rHH	0.741		0.740	-0.002	1	2
AsH3	Arsine	rAsH	1.511	±0.000	1.509	-0.002	1	2
GeH	germylidene	rGeH	1.588		1.587	-0.001	1	2
C3H4	cyclopropene	rCH	1.072		1.071	-0.001	2	4
OH-	hydroxide anion	rOH	0.964		0.963	-0.001	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.076	-0.001	1	3
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.257	-0.001	1	2
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
H2O	Water	rOH	0.958	±0.000	0.957	-0.001	1	2
CH3CCH	propyne	rCH	1.060		1.059	-0.001	3	4
CH3Br	methyl bromide	rCH	1.082	±0.001	1.082	-0.001	1	3
HF	Hydrogen fluoride	rHF	0.917	±0.000	0.917	0.000	1	2
SiH+	silicon monohydride cation	rSiH	1.504		1.504	0.000	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.086	0.000	2	5
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.081	0.000	1	2
C5H8O	Methyl cyclopropyl ketone	rCC	1.510		1.510	0.000	2	3
OH	Hydroxyl radical	rOH	0.970		0.970	0.000	1	2
CH3OC2H5	Ethane, methoxy-	rCH	1.086	±0.010	1.087	0.001	1	5
CH3OC2H5	Ethane, methoxy-	rCH	1.089	±0.008	1.090	0.001	4	10
HCl+	hydrogen chloride cation	rHCl	1.315		1.315	0.001	1	2
C10H8	Azulene	rCH	1.081		1.083	0.001	1	11
C10H8	Azulene	rCH	1.083		1.084	0.001	5	15
C2H3	vinyl	rCH	1.085		1.087	0.002	2	4
MgH	magnesium monohydride	rMgH	1.730		1.731	0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.090	0.002	4	6
SiH2F2	difluorosilane	rSiH	1.462		1.463	0.002	1	4
PO	Phosphorus monoxide	rP=O	1.476		1.478	0.002	1	2
C3H6O	2-Propen-1-ol	rCH	1.078	±0.010	1.080	0.002	3	8
CH3NH2	methyl amine	rCH	1.093	±0.000	1.095	0.002	1	3
C5H8	Ethenylcyclopropane	rCC	1.475		1.477	0.002	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.462	0.002	1	2
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.649	0.002	1	2
CH3OC2H5	Ethane, methoxy-	rCO	1.407	±0.004	1.409	0.002	2	3
NH3BF3	Amminetrifluoroboron	rBN	1.673		1.676	0.003	1	2
H2CS	Thioformaldehyde	rC=S	1.611		1.614	0.003	1	2
SiH	Silylidyne	rSiH	1.520		1.523	0.003	1	2
HS	Mercapto radical	rSH	1.341		1.344	0.003	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.150	0.004	2	4
GeS	Germanium monosulfide	rS=Ge	2.012	±0.000	2.016	0.004	1	2
HS-	mercapto anion	rSH	1.343		1.348	0.004	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.713	0.004	1	3
PH	phosphorus monohydride	rPH	1.422		1.427	0.004	1	2
GeF+	Germanium monofluoride cation	rFGe	1.665	±0.000	1.670	0.005	1	2
B2	Boron diatomic	rBB	1.590		1.597	0.007	1	2
C10H8	naphthalene	rC:C	1.410		1.417	0.007	2	3
NH2CONH2	Urea	rNH	0.998		1.005	0.007	4	8
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.470	0.008	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.501	0.008	2	3
SO+	sulfur monoxide cation	rO=S	1.424		1.432	0.008	1	2
C10H8	Azulene	rC:C	1.377		1.387	0.010	5	7
P2	Phosphorus diatomic	rP#P	1.893		1.903	0.010	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.746	0.010	1	2
TiCl	Titanium Monochloride	rClTi	2.265	±0.000	2.275	0.011	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.779	0.012	1	4
C10H8	Azulene	rC:C	1.484		1.497	0.013	7	8
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.947	0.013	1	2
C2H	Ethynyl radical	rCH	1.047		1.060	0.013	1	3
AsF	Arsenic monofluoride	rFAs	1.736	±0.001	1.751	0.015	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.712	0.015	1	3
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.793	0.016	1	4
NS	Mononitrogen monosulfide	rNS	1.497	±0.000	1.513	0.016	1	2
SOF4	Sulfur tetrafluoride oxide	rFS	1.596	±0.003	1.613	0.017	1	3
AlCl	Aluminum monochloride	rAlCl	2.130	±0.000	2.148	0.018	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.599	0.018	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.269	0.018	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.665	0.019	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.454	0.019	1	2
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.779	0.020	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.713	±0.003	1.733	0.020	1	4
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.116	0.021	1	2
SO	Sulfur monoxide	rS=O	1.481		1.503	0.022	1	2
C5H8O	Cyclopentanone	rCC	1.504		1.526	0.022	2	3
SiH3Cl	chlorosilane	rSiCl	2.051		2.073	0.022	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.567	0.022	1	4
PF2	Phosphorus difluoride	rPF	1.579		1.602	0.023	1	2
NaF	sodium fluoride	rNaF	1.926	±0.000	1.949	0.023	1	2
SF	Monosulfur monofluoride	rSF	1.599		1.623	0.024	1	2
SiF	silicon monofluoride	rSiF	1.604		1.628	0.024	1	2
SiH2Cl2	dichlorosilane	rSiCl	2.033	±0.003	2.057	0.024	1	4
SOF4	Sulfur tetrafluoride oxide	rFS	1.539	±0.003	1.565	0.026	1	5
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.655	0.027	1	2
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.087	0.028	1	3
AlC	Aluminum carbide	rC=Al	1.955		1.984	0.029	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.324	0.029	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.461	0.030	1	2
S2	Sulfur diatomic	rS=S	1.889		1.922	0.033	1	2
CFCl	chlorofluoromethylene	rCCl	1.714		1.749	0.035	1	3
LiO	lithium oxide	rLiO	1.688		1.723	0.035	1	2
BrO	Bromine monoxide	rOBr	1.718		1.755	0.038	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.602	0.038	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.059	0.039	1	2
NaCl	Sodium Chloride	rNaCl	2.361	±0.000	2.400	0.039	1	2
PS	phosphorus sulfide	rP=S	1.900		1.940	0.040	1	2
GaAs	Gallium arsenide	rGa#As	2.530	±0.020	2.570	0.040	1	2
ClOF3	Chlorine trifluoride oxide	rFCl	1.603	±0.004	1.644	0.041	1	3
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.213	0.043	1	2
SCl2	Sulfur dichloride	rSCl	2.013	±0.001	2.056	0.043	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.327	0.046	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.182	0.046	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.938	0.047	1	2
Cl2	Chlorine diatomic	rClCl	1.988		2.037	0.049	1	2
SCl	sulfur monochloride	rSCl	1.975		2.025	0.050	1	2
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.661	0.050	1	2
C4H8O2	Ethyl acetate	rCO	1.448		1.512	0.064	5	6
KH	Potassium hydride	rKH	2.243	±0.001	2.362	0.119	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.489	0.188	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.798	0.204	1	2
Al2Cl6	Aluminum, di-μ-chlorotetrachlorodi-	rAlCl	2.040	±0.040	2.272	0.232	1	3
C4H10O	Methyl propyl ether	rCH	1.099		1.405	0.306	1	2
CaO	Calcium monoxide	rOCa	1.822		2.178	0.356	1	2

227 molecules.