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

Listing of experimental geometry data for C5H4O2 (4-Cyclopentene-1,3-dione)

No experimental rotational constants available.
Calculated rotational constants for C5H4O2 (4-Cyclopentene-1,3-dione).

Point Group C2v

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 1.093 1 9 1987Kuchitsu(II/15)
rCO 1.208 3 7 1987Kuchitsu(II/15)
rCC 1.341 4 5 1987Kuchitsu(II/15)
rCC 1.509 3 5 1987Kuchitsu(II/15)
aHCC 118.7 5 4 10 1987Kuchitsu(II/15)
aCCC 110.4 3 5 4 1987Kuchitsu(II/15)
aCCO 124.9 1 3 7 1987Kuchitsu(II/15)
aHCH 113.2 8 1 9 1987Kuchitsu(II/15)
picture of 4-Cyclopentene-1,3-dione

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-C 4
C=C 1
C=O 2
H-C 4

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)

Calculated geometries for C5H4O2 (4-Cyclopentene-1,3-dione).

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squib reference DOI
1987Kuchitsu(II/15) Kuchitsu (ed.), Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 15: Structure Data of Free Polyatomic Molecules. Springer-Verlag, Berlin, 1987.  

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