National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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 C5H8 (Ethenylcyclopropane)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.50909 0.10212 0.09811
Rotational Constants from NISThydrocarbon
Calculated rotational constants for C5H8 (Ethenylcyclopropane).

Point Group Cs

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 1.475 3 4 1976Hellwege(II/7) out of ring
rCC 1.522 1 2 1976Hellwege(II/7) average, ring
rCC 1.334 4 5 1976Hellwege(II/7)
rCH 1.099 1 6 1976Hellwege(II/7) weighted average
aHCC 119.7 4 5 12 1976Hellwege(II/7) !assumed
aHCC 116.8 2 1 6 1976Hellwege(II/7) !assumed
aCCC 120.1 1 3 4 1976Hellwege(II/7) ring out
aCCC 126.2 3 4 5 1976Hellwege(II/7)
picture of Ethenylcyclopropane

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 4
C=C 1

Atom x (Å) y (Å) z (Å)
C1 1.4544 0.7624 -0.0476
C2 1.4591 -0.7586 -0.1025
C3 0.2363 -0.0198 0.4223
C4 -1.0082 0.0064 -0.3689
C5 -2.2508 -0.0092 0.1162
H6 2.1049 1.2332 0.7027
H7 1.4063 1.2928 -1.0090
H8 1.4140 -1.2186 -1.0995
H9 2.1127 -1.2781 0.6121
H10 0.0368 -0.0239 1.5031
H11 -0.9023 0.1374 -1.4549
H12 -2.4107 -0.0447 1.2029
H13 -3.1053 0.0137 -0.5745

Atom - Atom Distances (Å)

  C1 C2 C3 C4 C5 H6 H7 H8 H9 H10 H11 H12 H13

Calculated geometries for C5H8 (Ethenylcyclopropane).
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
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.  
NISThydrocarbon NIST Hydrocarbon spectral database (  

Got a better number? Please email us at