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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
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XIVReaction data
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XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Listing of experimental geometry data for C5H6 (Cyclopropylacetylene)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.52446 0.11208 0.10650
Rotational Constants from 1983Har/Nan:3947
Calculated rotational constants for C5H6 (Cyclopropylacetylene).

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 1.527 1 4 1983Har/Nan:3947
rCC 1.503 4 5 1983Har/Nan:3947
rCC 1.422 1 2 1983Har/Nan:3947
rCC 1.211 2 6 1983Har/Nan:3947
rCH 1.055 6 7 1983Har/Nan:3947
rCH 1.080 1 3 1983Har/Nan:3947
aHCH 114.6 8 4 9 1983Har/Nan:3947
aHCC 109.5 2 1 3 1983Har/Nan:3947
aCCC 119.3 2 1 4 1983Har/Nan:3947
picture of Cyclopropylacetylene

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 4
C#C 1

Atom x (Å) y (Å) z (Å)
C1 -0.2523 0.0000 0.5778
C2 1.1078 0.0000 0.1626
H3 -0.3254 0.0000 1.6553
C4 -1.3015 0.7519 -0.2372
C5 -1.3015 -0.7519 -0.2372
C6 2.2669 0.0000 -0.1881
H7 3.2764 0.0000 -0.4944
H8 -2.0662 1.2729 0.3108
H9 -0.9672 1.2571 -1.1247
H10 -2.0662 -1.2729 0.3108
H11 -0.9672 -1.2571 -1.1247

Atom - Atom Distances (Å)

  C1 C2 H3 C4 C5 C6 H7 H8 H9 H10 H11

Calculated geometries for C5H6 (Cyclopropylacetylene).
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squib reference DOI
1983Har/Nan:3947 Harmony, Nandi, Tietyz, Choe, Getty, Staley, Microwave Structures of Cyanocyclopropane and Cyclopropylacetylene. Effects of Cycloproply Conjugation on Structure, J. Am. Chem. Soc., Vol. 105, pgs. 3947-3951 10.1021/ja00350a034

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