National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
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XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
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XVIBibliographic data
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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