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

Listing of experimental geometry data for C4H6 (1-Methylcyclopropene)

Rotational Constants (cm-1)
See section I.F.4 to change rotational constant units
0.68547 0.21205 0.17267
Rotational Constants from
Calculated rotational constants for C4H6 (1-Methylcyclopropene).

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
rCH 1.070 1 2 1976Hellwege(II/7) !assumed
rCC 1.515 2 6 1976Hellwege(II/7) !assumed, opp extra C
rCC 1.300 2 3 1976Hellwege(II/7) !assumed
rCH 1.087 4 6 1976Hellwege(II/7) !assumed, C with 2 H
rCH 1.087 5 6 1976Hellwege(II/7) !assumed, C with 2 H
rCH 1.085 7 10 1976Hellwege(II/7) !assumed, C outside ring
rCH 1.098 8 10 1976Hellwege(II/7) !assumed, C outside ring
rCH 1.098 9 10 1976Hellwege(II/7) !assumed, C outside ring
rCC 1.476 3 6 1976Hellwege(II/7)
aHCC 150 1 2 3 1976Hellwege(II/7) !assumed
aHCH 114.7 4 6 5 1976Hellwege(II/7) !assumed, C with 2 H
aCCC 50.8 2 5 3 1976Hellwege(II/7) !assumed, C with 2 H in middle
aHCC 111 3 10 7 1976Hellwege(II/7) !assumed, to methyl
aCCC 152.8 2 3 10 1976Hellwege(II/7) to methyl C
aHCH 109 7 10 8 1976Hellwege(II/7) !assumed, C outside ring
aHCH 109 8 10 9 1976Hellwege(II/7) !assumed, C outside ring
picture of 1-Methylcyclopropene

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 6
C-C 3
C=C 1

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)

Calculated geometries for C4H6 (1-Methylcyclopropene).

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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.  

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