National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
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 CH3 (Methyl radical)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
9.57789 9.57789 4.74202
Rotational Constants from 1981Yam/Hir:5256
Calculated rotational constants for CH3 (Methyl radical).

Point Group D3h

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 1.079 1 2 1966Herzberg
aHCH 120 2 1 3 1966Herzberg
picture of Methyl radical

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.0000
H2 1.0790 0.0000 0.0000
H3 -0.5395 -0.9344 0.0000
H4 -0.5395 0.9344 0.0000

Atom - Atom Distances (Å)

  C1 H2 H3 H4

Calculated geometries for CH3 (Methyl radical).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1981Yam/Hir:5256 Yamada, C.; Hirota, E. Kawaguchi, K. "Diode laser study of the (nu)2 band of the methyl radical." Journal of Chemical Physics. 75, 5256-5264 (1981) 10.1063/1.441991

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