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
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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 MP4=FULL/Def2TZVPP

Species	Name	Bond type	Bond Length (Å)
			Experimental	unc.	Calculated	Difference	atom1	atom2
SiP	Silicon monophosphide	rSiP	2.078	±0.002	2.002	-0.075	1	2
CH3CH2CH2CH3	Butane	rCH	1.117		1.093	-0.024	1	5
LiOH	lithium hydroxide	rOH	0.969		0.949	-0.020	1	3
H2Cl+	dihydrogen monochloride cation	rHCl	1.321	±0.000	1.301	-0.020	1	2
ArH+	Argon hydride cation	rArH	1.292	±0.000	1.275	-0.017	1	2
CO+	carbon monoxide cation	rC=O	1.115	±0.000	1.098	-0.017	1	2
HI+	Hydrogen iodide cation	rHI	1.632	±0.000	1.616	-0.016	1	2
B2H6	Diborane	rBH	1.200		1.184	-0.016	1	5
HSe	Selenium monohydride	rSeH	1.475	±0.010	1.460	-0.015	1	2
CH3CH2CHO	Propanal	rCH	1.103		1.088	-0.015	1	6
HS+	sulfur monohydride cation	rSH	1.374		1.360	-0.014	1	2
HeH+	Helium hydride cation	rHHe	0.790		0.776	-0.014	1	2
HI	Hydrogen iodide	rHI	1.609	±0.000	1.595	-0.014	1	2
NO	Nitric oxide	rN=O	1.154	±0.000	1.141	-0.013	1	2
CH2NH	Methanimine	rCH	1.103		1.090	-0.013	1	3
B2H6	Diborane	rBH	1.320		1.308	-0.012	1	3
CH3I	methyl iodide	rCI	2.136	±0.002	2.125	-0.011	1	2
CH3CH2CHO	Propanal	rCH	1.105		1.095	-0.010	2	8
As4	Arsenic tetramer	rAsAs	2.435		2.425	-0.010	1	2
ICN	Cyanogen iodide	rCI	1.992	±0.000	1.982	-0.010	1	2
NH2SH	Thiohydroxylamine	rSH	1.344	±0.029	1.336	-0.008	2	3
CH3CH2CHO	Propanal	rCH	1.115		1.107	-0.008	3	10
HOCl	hypochlorous acid	rOH	0.973	±0.002	0.965	-0.008	1	2
CH3CHO	Acetaldehyde	rCH	1.114		1.106	-0.008	1	4
CH3CH2CHO	Propanal	rCH	1.096		1.088	-0.008	1	5
CH3CCH	propyne	rCH	1.096		1.089	-0.007	1	5
CH2CO	Ketene	rCH	1.083		1.076	-0.007	1	4
CI4	tetraiodomethane	rCI	2.157	±0.010	2.151	-0.006	1	2
CH3CH2SH	ethanethiol	rCH	1.095		1.089	-0.006	1	4
HBr+	hydrogen bromide cation	rHBr	1.448		1.443	-0.006	1	2
CH3CH2CH2CH3	Butane	rCC	1.531		1.526	-0.005	1	2
H2Se	Hydrogen selenide	rSeH	1.460		1.455	-0.005	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.093	±0.006	1.088	-0.005	4	8
SiH3Cl	chlorosilane	rSiH	1.475		1.470	-0.005	1	3
HCl+	hydrogen chloride cation	rHCl	1.315		1.310	-0.005	1	2
MgH	magnesium monohydride	rMgH	1.730		1.725	-0.004	1	2
CH3CHFCH3	2-Fluoropropane	rCH	1.094	±0.005	1.090	-0.004	4	10
KrH+	Protonated Krypton	rHKr	1.421	±0.000	1.417	-0.004	1	2
C3H8	Propane	rCH	1.096		1.092	-0.004	1	4
HBr	hydrogen bromide	rHBr	1.414	±0.000	1.411	-0.003	1	2
C3H4	cyclopropene	rCH	1.088		1.085	-0.003	1	6
CH2Cl2	Methylene chloride	rCH	1.085	±0.002	1.082	-0.003	1	2
He2+	helium diatomic cation	rHeHe	1.081	±0.001	1.078	-0.003	1	2
CH3CH2SH	ethanethiol	rCH	1.092		1.089	-0.003	1	5
CH3CH2SH	ethanethiol	rCH	1.090		1.088	-0.002	2	7
HS-	mercapto anion	rSH	1.343		1.341	-0.002	1	2
CH3CH2CHO	Propanal	rCC	1.523		1.521	-0.002	1	2
PH	phosphorus monohydride	rPH	1.422		1.420	-0.002	1	2
CH3CH2CHO	Propanal	rCC	1.509		1.507	-0.002	2	3
C2H6O2S	Dimethyl sulfone	rCS	1.777	±0.006	1.775	-0.002	1	4
CH3I	methyl iodide	rCH	1.084	±0.003	1.082	-0.002	1	3
CBr4	Carbon tetrabromide	rCBr	1.942	±0.002	1.941	-0.001	1	2
C2H5I	Ethyl iodide	rHC	1.093		1.092	-0.001	2	6
CH3CHFCH3	2-Fluoropropane	rCH	1.092		1.091	-0.001	1	3
OH	Hydroxyl radical	rOH	0.970		0.969	0.000	1	2
C2H2+	acetylene cation	rCH	1.077	±0.005	1.077	0.000	1	3
C2H2+	acetylene cation	rC=C	1.253	±0.001	1.253	0.000	1	2
LiNH2	lithium amide	rLiN	1.736	±0.003	1.736	0.000	1	2
SiH3+	Silyl cation	rSiH	1.460	±0.010	1.460	0.000	1	2
CH3Br	methyl bromide	rCH	1.082	±0.001	1.083	0.000	1	3
CH3CHO	Acetaldehyde	rCH	1.086		1.086	0.000	2	5
CH3CCH	propyne	rCH	1.060		1.061	0.001	3	4
C3H4	cyclopropene	rCH	1.072		1.073	0.001	2	4
H2O	Water	rOH	0.958	±0.000	0.959	0.001	1	2
SiH2F2	difluorosilane	rSiH	1.462		1.463	0.001	1	4
LiOH	lithium hydroxide	rLiO	1.582		1.583	0.001	1	2
CH2Br2	dibromomethane	rCBr	1.925	±0.002	1.927	0.002	1	4
CH3CHFCH3	2-Fluoropropane	rCH	1.088	±0.006	1.090	0.002	4	6
CH3Br	methyl bromide	rCBr	1.934	±0.000	1.936	0.002	1	2
ICl	Iodine monochloride	rClI	2.321	±0.000	2.324	0.003	1	2
C2H3	vinyl	rCH	1.085		1.088	0.003	2	4
HOCl	hypochlorous acid	rClO	1.697	±0.001	1.701	0.003	1	3
SiH3Cl	chlorosilane	rSiCl	2.051		2.054	0.003	1	2
CF	Fluoromethylidyne	rCF	1.276		1.280	0.004	1	2
CH2Cl2	Methylene chloride	rCCl	1.767	±0.002	1.771	0.004	1	4
OCSe	Carbonyl selenide	rC=Se	1.709		1.714	0.005	1	3
H2CS	Thioformaldehyde	rC=S	1.611		1.616	0.005	1	2
I2	Iodine diatomic	rII	2.665		2.671	0.005	1	2
F2	Fluorine diatomic	rFF	1.412		1.418	0.006	1	2
IF	Iodine monofluoride	rFI	1.910		1.916	0.006	1	2
HNCNH	diiminomethane	rC=N	1.224	±0.001	1.231	0.007	1	2
SF4	Sulfur tetrafluoride	rSF	1.646	±0.003	1.654	0.008	1	2
IBr	Iodine monobromide	rBrI	2.469	±0.000	2.477	0.008	1	2
LiCl	lithium chloride	rLiCl	2.021	±0.000	2.029	0.009	1	2
IO	Iodine monoxide	rIO	1.868	±0.004	1.877	0.009	1	2
BO	boron monoxide	rB=O	1.205		1.213	0.009	1	2
PF2	Phosphorus difluoride	rPF	1.579		1.588	0.009	1	2
CH2CO	Ketene	rC=O	1.162		1.172	0.010	2	3
BrF	Bromine monofluoride	rFBr	1.759	±0.000	1.769	0.010	1	2
SF4	Sulfur tetrafluoride	rSF	1.545	±0.003	1.556	0.011	1	4
Br2	Bromine diatomic	rBrBr	2.281		2.293	0.012	1	2
LiF	lithium fluoride	rLiF	1.564	±0.000	1.576	0.012	1	2
ClF	Chlorine monofluoride	rFCl	1.628	±0.000	1.641	0.013	1	2
BrCl	Bromine monochloride	rClBr	2.136	±0.000	2.149	0.013	1	2
LiI	Lithium Iodide	rLiI	2.392	±0.000	2.405	0.014	1	2
SeO	Selenium monoxide	rSeO	1.639	±0.001	1.653	0.014	1	2
OCSe	Carbonyl selenide	rC=O	1.159		1.173	0.014	1	2
ICN	Cyanogen iodide	rC#N	1.160	±0.000	1.175	0.014	2	3
CH2I2	Diiodomethane	rCH	1.066	±0.015	1.081	0.015	1	4
C2H6O2S	Dimethyl sulfone	rS=O	1.431	±0.004	1.447	0.016	1	2
SiBr+	Silicon monobromide cation	rSiBr	2.095	±0.000	2.111	0.016	1	2
SCSe	Carbon sulfide selenide	rC=S	1.553	±0.002	1.569	0.016	1	2
SCSe	Carbon sulfide selenide	rC=Se	1.695	±0.002	1.712	0.017	1	3
S2	Sulfur diatomic	rS=S	1.889		1.906	0.017	1	2
LiBr	Lithium Bromide	rLiBr	2.170	±0.000	2.188	0.018	1	2
KH	Potassium hydride	rKH	2.243	±0.001	2.262	0.020	1	2
NO+	nitric oxide cation	rN=O	1.066		1.086	0.020	1	2
XeF2	Xenon difluoride	rFXe	1.974	±0.000	1.998	0.024	1	2
XeF4	Xenon tetrafluoride	rFXe	1.935	±0.000	1.963	0.028	1	2
C3O2	Carbon suboxide	rC=C	1.251		1.280	0.029	1	2
C3O2	Carbon suboxide	rC=O	1.146		1.177	0.031	2	4
PS	phosphorus sulfide	rP=S	1.900		1.934	0.034	1	2
SO+	sulfur monoxide cation	rO=S	1.424		1.459	0.035	1	2
SeO2	Selenium dioxide	rSeO	1.607	±0.001	1.643	0.036	1	2
CaO	Calcium monoxide	rOCa	1.822		2.226	0.404	1	2

115 molecules.