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Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
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XXH-bond dimers

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

Listing of experimental geometry data for C5H8 (Ethenylcyclopropane)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.50909 0.10212 0.09811
Rotational Constants from NISThydrocarbon
Calculated rotational constants for C5H8 (Ethenylcyclopropane).

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 1.475 1 2 1976Hellwege(II/7) out of ring
rCC 1.522 1 4 1976Hellwege(II/7) average, ring
rCC 1.334 2 3 1976Hellwege(II/7)
rCH 1.099 1 6 1976Hellwege(II/7) weighted average
aHCC 119.7 3 2 7 1976Hellwege(II/7) !assumed
aHCC 116.8 1 4 10 1976Hellwege(II/7) !assumed
aCCC 120.1 2 1 4 1976Hellwege(II/7) ring out
aCCC 126.2 1 2 3 1976Hellwege(II/7)
picture of Ethenylcyclopropane

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 8
C-C 4
C=C 1

Atom x (Å) y (Å) z (Å)
C1 1.4544 0.7624 -0.0476
C2 1.4591 -0.7586 -0.1025
C3 0.2363 -0.0198 0.4223
C4 -1.0082 0.0064 -0.3689
C5 -2.2508 -0.0092 0.1162
H6 2.1049 1.2332 0.7027
H7 1.4063 1.2928 -1.0090
H8 1.4140 -1.2186 -1.0995
H9 2.1127 -1.2781 0.6121
H10 0.0368 -0.0239 1.5031
H11 -0.9023 0.1374 -1.4549
H12 -2.4107 -0.0447 1.2029
H13 -3.1053 0.0137 -0.5745

Atom - Atom Distances (Å)

  C1 C2 C3 C4 C5 H6 H7 H8 H9 H10 H11 H12 H13

Calculated geometries for C5H8 (Ethenylcyclopropane).
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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.  
NISThydrocarbon NIST Hydrocarbon spectral database ( 10.18434/T4PC70

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