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 C5H8O (Cyclopentanone)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.22090 0.11180 0.08040
Rotational Constants from 1969Kim/Gwi:1815
Calculated rotational constants for C5H8O (Cyclopentanone).

Point Group C2

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
rCO 1.215 13 14 1976Hellwege(II/7) !assumed
rCH 1.095 1 2 1976Hellwege(II/7) !assumed
rCC 1.504 7 13 1976Hellwege(II/7) C has =O
rCC 1.557 1 4 1976Hellwege(II/7)
aHCH 110 2 1 3 1976Hellwege(II/7)
aCCC 110.5 7 13 10 1976Hellwege(II/7) center C has =O
aCCC 104.5 4 7 13 1976Hellwege(II/7) going away from =O
aCCC 103 1 4 7 1976Hellwege(II/7)
picture of Cyclopentanone

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 8
C-C 5
C=O 1

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)


Calculated geometries for C5H8O (Cyclopentanone).
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squib reference DOI
1969Kim/Gwi:1815 Kim, H.; Gwinn, W. "Ring Puckering Five-Membered Rings. III. The Microwave Spectrum, Dipole Moment, and Structure of Cyclopentanone." Journal of Chemical Physics. 51, 1815-1819 (1969) 10.1063/1.1672263
1976Hellwege(II/7) Hellwege, KH and AM Hellwege (ed.). Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 7: Structure Data of Free Polyatomic Molecules. Springer-Verlag. Berlin. 1976.  

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