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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
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XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
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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 C3H5 (Allyl radical)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
1.80189 0.34632 0.29022
Rotational Constants from 1992Hir/Yam:2963
Calculated rotational constants for C3H5 (Allyl radical).

Point Group

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
rCC 1.428 1 3 1986Vaj/Tre:4352
rCH 1.069 1 2 1986Vaj/Tre:4352 mean of all CH bonds
aCCC 124.6 3 1 4 1986Vaj/Tre:4352
aHCC 120.9 1 3 5 1986Vaj/Tre:4352 middle C - C - H
aHCC 117.7 2 1 3 1986Vaj/Tre:4352 by symmetry
picture of Allyl radical

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C=C 1
H-C 1
H-C 4
C-C 1

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.0000
H2 0.0000 1.0690 0.0000
C3 -1.2643 -0.6638 0.0000
C4 1.2643 -0.6638 0.0000
H5 -2.1768 -0.1068 0.0000
H6 2.1768 -0.1068 0.0000
H7 -1.2643 -1.7328 0.0000
H8 1.2643 -1.7328 0.0000

Atom - Atom Distances (Å)

  C1 H2 C3 C4 H5 H6 H7 H8

Calculated geometries for C3H5 (Allyl radical).
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squib reference DOI
1986Vaj/Tre:4352 Vajda, E., Tremmel, J., Rozsondai, B., Hargittai, I., Maltsev, A. K., Kagramanov, N. D., Nefedov, O. M., Molecular Structure of Allyl Radical from Electron Diffraction, J. Am. Chem. Soc. 108 4352-4353 10.1021/ja00275a020
1992Hir/Yam:2963 Hirota, E.; Yamada, C.; Okunishi, M. "Infrared diode alser spectroscopy of the allyl radical. The (nu)11 band." Journal of Chemical Physics. 97, 2963-2970 (1992) 10.1063/1.463037

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