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

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to

return to home page

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

Listing of experimental geometry data for C3H4O (Cyclopropanone)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.67226 0.24906 0.19586
Rotational Constants from 1968Poc/Bal:1072
Calculated rotational constants for C3H4O (Cyclopropanone).

Point Group C2v

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 1.191 1 2 1976Hellwege(II/7)
rCC 1.475 1 3 1976Hellwege(II/7)
rCC 1.575 3 4 1976Hellwege(II/7) opposite =C
rCH 1.086 3 5 1976Hellwege(II/7)
aCCC 57.7 1 3 4 1976Hellwege(II/7)
aHCH 114.1 5 3 6 1976Hellwege(II/7)
aCCC 64.6 3 1 4 1976Hellwege(II/7) middle C has =O
aCCO 147.7 2 1 3 1976Hellwege(II/7) by symmetry
picture of Cyclopropanone

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 4
C-C 3
C=O 1

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.3856
O2 0.0000 0.0000 1.5762
C3 0.0000 0.7876 -0.8610
C4 0.0000 -0.7876 -0.8610
H5 0.9114 1.3027 -1.1479
H6 -0.9114 1.3027 -1.1479
H7 -0.9114 -1.3027 -1.1479
H8 0.9114 -1.3027 -1.1479

Atom - Atom Distances (Å)

  C1 O2 C3 C4 H5 H6 H7 H8

Calculated geometries for C3H4O (Cyclopropanone).
By selecting the following links, you may be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to
squib reference DOI
1968Poc/Bal:1072 JM Pochan, JE Baldwin, WH Flygare "Microwave Spectrum, Structure, and Dipole Moment in Cyclopropanone" JACS 90:4 1072, 1968 10.1021/ja01006a049
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.  

Got a better number? Please email us at