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

Listing of experimental geometry data for CH2CCH2 (allene)

Rotational Constants (cm-1)
See section I.F.4 to change rotational constant units
4.81000 0.29632 0.29632
Rotational Constants from 1966Herzberg
Calculated rotational constants for CH2CCH2 (allene).

Point Group D2d

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 1.308 1 2 1966Herzberg
rCH 1.087 2 4 1966Herzberg
aHCH 118.2 4 2 5 1966Herzberg
aHCC 120.9 1 2 4 1966Herzberg by symmetry
picture of allene

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C=C 2
H-C 4

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.0000
C2 0.0000 0.0000 1.3080
C3 0.0000 0.0000 -1.3080
H4 0.0000 0.9327 1.8662
H5 0.0000 -0.9327 1.8662
H6 0.9327 0.0000 -1.8662
H7 -0.9327 0.0000 -1.8662

Atom - Atom Distances (Å)
  C1 C2 C3 H4 H5 H6 H7

Calculated geometries for CH2CCH2 (allene).

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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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