National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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II.A.3. (XII.A.1.)

Listing of experimental geometry data for CH3I (methyl iodide)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
5.17340 0.25021 0.25021
Rotational Constants from 1975mal:94
Calculated rotational constants for CH3I (methyl iodide).

Point Group C3v

Internal coordinates

(distances (r) in Å) (angles (a) in degrees) (dihedrals (d) in degrees)
Description Value Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rCH 1.084 1 3 1998Kuc rs
rCI 2.136 1 2 1998Kuc rs
aHCI 107.47 2 1 3 1998Kuc
aHCH 111.4 3 1 4 by symmetry
picture of methyl iodide

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-I 1
H-C 3

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 -1.8100
I2 0.0000 0.0000 0.3258
H3 0.0000 1.0340 -2.1354
H4 0.8955 -0.5170 -2.1354
H5 -0.8955 -0.5170 -2.1354

Atom - Atom Distances (Å)

  C1 I2 H3 H4 H5

Calculated geometries for CH3I (methyl iodide).
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squib reference DOI
1975mal:94 PD Mallinson "The microwave spectrum of CH2DI" J. Molecular Spectroscopy 55, 94-107 (1975) 10.1016/0022-2852(75)90255-6
1998Kuc K Kuchitsu(ed) "Structure of Free Polyatomic Molecules - Basic Data" Springer, Berlin, 1998 10.1007/978-3-642-45748-7 

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