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

Listing of experimental geometry data for C2H4 (Ethylene)

Rotational Constants (cm-1)
See section I.F.4 to change rotational constant units
4.82800 1.00120 0.82820
Rotational Constants from 1966Herzberg
Calculated rotational constants for C2H4 (Ethylene).

Point Group D2h

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 1.339 1 2 1966Herzberg
rCH 1.086 1 3 1966Herzberg
aHCH 117.6 3 1 4 1966Herzberg
aHCC 121.2 1 2 5 1966Herzberg
picture of Ethylene

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 4

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.6695
C2 0.0000 0.0000 -0.6695
H3 0.0000 0.9289 1.2321
H4 0.0000 -0.9289 1.2321
H5 0.0000 0.9289 -1.2321
H6 0.0000 -0.9289 -1.2321

Atom - Atom Distances (Å)
  C1 C2 H3 H4 H5 H6

Calculated geometries for C2H4 (Ethylene).

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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  

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