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
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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/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	1.980	-0.098	1	2
CrH	Chromium hydride	rHCr	1.655	±0.001	1.563	-0.092	1	2
CN	Cyano radical	rC#N	1.172		1.128	-0.044	1	2
C3F6	hexafluoropropene	rCF	1.329	±0.003	1.302	-0.027	1	4
LiOH	lithium hydroxide	rOH	0.969		0.942	-0.027	1	3
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.089	-0.027	1	2
F2	Fluorine diatomic	rFF	1.412		1.386	-0.026	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.092	-0.025	1	5
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.583	-0.024	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.130	-0.024	1	2
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.300	-0.020	1	2
XeF4	Xenon tetrafluoride	rFXe	1.935	±0.000	1.917	-0.018	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.275	-0.017	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.142	-0.017	1	2
IF	Iodine monofluoride	rFI	1.910		1.893	-0.016	1	2
NO+	nitric oxide cation	rN=O	1.066		1.049	-0.016	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.087	-0.016	1	6
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.624	-0.016	1	2
XeF2	Xenon difluoride	rFXe	1.974	±0.000	1.959	-0.015	1	2
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.958	-0.015	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.631	-0.015	1	2
HI+	Hydrogen iodide cation	rHI	1.632	±0.000	1.617	-0.015	1	2
HS+	sulfur monohydride cation	rSH	1.374		1.359	-0.015	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.775	-0.015	1	2
CH2NH	Methanimine	rCH	1.103		1.089	-0.014	1	3
B2H6	Diborane	rBH	1.200		1.186	-0.014	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.461	-0.014	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.411	-0.013	1	2
HI	Hydrogen iodide	rHI	1.609	±0.000	1.596	-0.013	1	2
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.685	-0.013	1	3
CH3CH2CHO	Propanal	rCH	1.115		1.103	-0.012	3	10
CH3CH2CHO	Propanal	rCH	1.105		1.093	-0.012	2	8
CF	Fluoromethylidyne	rCF	1.276		1.264	-0.012	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.102	-0.012	1	4
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.542	-0.011	1	2
ICN	Cyanogen iodide	rC#N	1.160	±0.000	1.150	-0.011	2	3
OPCl	Phosphorus oxychloride	rP=O	1.462	±0.011	1.452	-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	1.749	-0.010	1	2
CH3I	methyl iodide	rCI	2.136	±0.002	2.126	-0.010	1	2
As4	Arsenic tetramer	rAsAs	2.435		2.425	-0.010	1	2
CH2CO	Ketene	rC=O	1.162		1.153	-0.009	2	3
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.335	-0.009	2	3
CI4	tetraiodomethane	rCI	2.157	±0.010	2.148	-0.009	1	2
CH3CH2CHO	Propanal	rCH	1.096		1.087	-0.009	1	5
B2H6	Diborane	rBH	1.320		1.312	-0.008	1	3
CH3CCH	propyne	rCH	1.096		1.088	-0.008	1	5
BO	boron monoxide	rB=O	1.205		1.196	-0.008	1	2
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.769	-0.008	1	4
CH2CO	Ketene	rCH	1.083		1.074	-0.008	1	4
CH3CSNH2	Ethanethioamide	rC=S	1.647	±0.002	1.640	-0.007	1	2
CH3CHS	Thioacetaldehyde	rCH	1.098		1.091	-0.007	2	6
H2CS	Thioformaldehyde	rC=S	1.611		1.604	-0.007	1	2
CH3CH2SH	ethanethiol	rCH	1.095		1.088	-0.007	1	4
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.539	-0.006	1	4
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.622	-0.006	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.087	-0.006	4	8
NO-	nitric oxide anion	rN=O	1.258	±0.010	1.252	-0.006	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.689	-0.006	1	3
ICN	Cyanogen iodide	rCI	1.992	±0.000	1.986	-0.006	1	2
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.416	-0.006	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.574	-0.006	1	2
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.079	-0.006	1	2
C3H8	Propane	rCH	1.096		1.090	-0.006	1	4
HBr+	hydrogen bromide cation	rHBr	1.448		1.443	-0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.089	-0.005	4	10
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.076	-0.005	1	2
CH2CHCH2CH3	1-Butene	rCC	1.536		1.531	-0.005	1	2
CH3CHS	Thioacetaldehyde	rCH	1.090		1.085	-0.005	2	5
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.248	-0.005	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.526	-0.005	1	2
HCl+	hydrogen chloride cation	rHCl	1.315		1.310	-0.005	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.220	-0.004	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.505	-0.004	2	3
CH3CH2SH	ethanethiol	rCH	1.090		1.086	-0.004	2	7
SiH3Cl	chlorosilane	rSiH	1.475		1.471	-0.004	1	3
C3H4	cyclopropene	rCH	1.088		1.084	-0.004	1	6
H2O	Water	rOH	0.958	±0.000	0.954	-0.004	1	2
CH3CH2SH	ethanethiol	rCH	1.092		1.088	-0.004	1	5
C3F6	hexafluoropropene	rC=C	1.329	±0.003	1.325	-0.004	1	2
OH	Hydroxyl radical	rOH	0.970		0.966	-0.003	1	2
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.411	-0.003	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.457	-0.003	1	2
CH3I	methyl iodide	rCH	1.084	±0.003	1.081	-0.003	1	3
HS-	mercapto anion	rSH	1.343		1.340	-0.003	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.922	-0.003	1	4
CH3CHS	Thioacetaldehyde	rCH	1.089		1.086	-0.003	1	4
C2H5I	Ethyl iodide	rHC	1.093		1.090	-0.003	2	6
CH3CH2CHO	Propanal	rCC	1.523		1.521	-0.002	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.090	-0.002	1	3
PH	phosphorus monohydride	rPH	1.422		1.420	-0.002	1	2
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.429	-0.002	1	2
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.932	-0.002	1	2
CH3CHO	Acetaldehyde	rCH	1.086		1.085	-0.001	2	5
CH3Br	methyl bromide	rCH	1.082	±0.001	1.081	-0.001	1	3
C3H4	cyclopropene	rCH	1.072		1.071	-0.001	2	4
MgH	magnesium monohydride	rMgH	1.730		1.729	0.000	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.077	0.000	1	3
CH3CCH	propyne	rCH	1.060		1.060	0.000	3	4
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.089	0.001	4	6
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.461	0.001	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.768	0.001	1	4
OPCl	Phosphorus oxychloride	rPCl	2.059	±0.004	2.060	0.001	1	3
C2H3	vinyl	rCH	1.085		1.086	0.001	2	4
LiNH2	lithium amide	rLiN	1.736	±0.003	1.737	0.001	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.463	0.002	1	4
ICl	Iodine monochloride	rClI	2.321	±0.000	2.323	0.002	1	2
LiOH	lithium hydroxide	rLiO	1.582		1.584	0.003	1	2
OCSe	Carbonyl selenide	rC=Se	1.709		1.712	0.003	1	3
C3O2	Carbon suboxide	rC=O	1.146		1.149	0.003	2	4
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.100	0.004	1	2
S2	Sulfur diatomic	rS=S	1.889		1.894	0.005	1	2
SiH3Cl	chlorosilane	rSiCl	2.051		2.056	0.006	1	2
Cl2+	chlorine diatomic cation	rClCl	1.892		1.898	0.006	1	2
IBr	Iodine monobromide	rBrI	2.469	±0.000	2.476	0.007	1	2
CH2CHCH2CH3	1-Butene	rCC	1.493		1.501	0.008	2	3
LiF	lithium fluoride	rLiF	1.564	±0.000	1.573	0.009	1	2
I2	Iodine diatomic	rII	2.665		2.675	0.010	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.146	0.010	1	2
Br2	Bromine diatomic	rBrBr	2.281		2.291	0.010	1	2
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.078	0.012	1	4
NCl	nitrogen monochloride	rNCl	1.611	±0.000	1.623	0.012	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.036	0.015	1	2
AlBr	Aluminum monobromide	rAlBr	2.295		2.312	0.017	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.273	0.022	1	2
LiI	Lithium Iodide	rLiI	2.392	±0.000	2.415	0.023	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.195	0.025	1	2
IO	Iodine monoxide	rIO	1.868	±0.004	1.894	0.026	1	2
CaO	Calcium monoxide	rOCa	1.822		1.865	0.043	1	2
CaC	Calcium monocarbide	rC#Ca	2.302		2.355	0.054	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.319	0.077	1	2
CaBr	Calcium monobromide	rCaBr	2.594	±0.000	2.672	0.078	1	2
C4H10O	Methyl propyl ether	rCH	1.099		1.404	0.305	1	2

134 molecules.