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 C2H3 (vinyl)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
7.90934 1.08303 0.94864
Rotational Constants from 1990Kan/End:197
Calculated rotational constants for C2H3 (vinyl).

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 1.316 1 2 1998Kuc
rCH 1.085 2 4 1998Kuc r0 values assumed
rCH 1.080 1 3 1998Kuc !assumed
aHCC 137.3 2 1 3 1998Kuc
aHCC 121.5 1 2 4 1998Kuc
picture of vinyl

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
C=C 1

Atom x (Å) y (Å) z (Å)
C1 0.0488 0.7245 0.0000
C2 0.0488 -0.5915 0.0000
H3 -0.6836 1.5182 0.0000
H4 -0.8763 -1.1584 0.0000
H5 0.9739 -1.1584 0.0000

Atom - Atom Distances (Å)

  C1 C2 H3 H4 H5

Calculated geometries for C2H3 (vinyl).
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
1990Kan/End:197 Kanamori, H.; Endo, Y.; Hirota, E. "The vinyl radical investigated by infrared diode laser kindetic spectroscopy." Journal of Chemical Physics. 92, 197-205 (1990) 10.1063/1.458462
1998Kuc K Kuchitsu(ed) "Structure of Free Polyatomic Molecules - Basic Data" Springer, Berlin, 1998  

Got a better number? Please email us at