National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
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 C4H6 (Bicyclo[1.1.0]butane)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.57747 0.31067 0.27998
Rotational Constants from 1966Har/Cox:5049
Calculated rotational constants for C4H6 (Bicyclo[1.1.0]butane).

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
rCC 1.497 1 2 1969Cox/Har:1976 across ring
rCC 1.498 1 3 1969Cox/Har:1976
rCH 1.093 3 8 1969Cox/Har:1976 corner of ring
rCH 1.071 1 9 1969Cox/Har:1976 in middle
aCCC 60 2 1 3 1969Cox/Har:1976 across center and to corner
aCCC 60 1 3 2 1969Cox/Har:1976 corner of ring
aCCC 98.3 3 1 4 1969Cox/Har:1976 across a side
aHCH 115.6 5 4 7 1969Cox/Har:1976
aHCC 116.9 1 3 8 1969Cox/Har:1976 corner to middle
aHCC 118.1 1 3 6 1969Cox/Har:1976 corner to middle
aHCC 129.9 3 1 9 1969Cox/Har:1976 corner to middle H
aHCC 128.4 1 2 10 1969Cox/Har:1976 across center to H
picture of Bicyclo[1.1.0]butane

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-C 5
H-C 6

Atom x (Å) y (Å) z (Å)
C1 0.7485 0.0000 -0.3163
C2 -0.7485 0.0000 -0.3163
C3 0.0000 1.1346 0.3126
C4 0.0000 -1.1346 0.3126
H5 0.0000 -1.1537 1.4054
H6 0.0000 1.1537 1.4054
H7 0.0000 -2.0850 -0.2273
H8 0.0000 2.0850 -0.2273
H9 1.4137 0.0000 -1.1557
H10 -1.4137 0.0000 -1.1557

Atom - Atom Distances (Å)

  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10

Calculated geometries for C4H6 (Bicyclo[1.1.0]butane).
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squib reference DOI
1966Har/Cox:5049 Harmoy, M; Cox, K. "Microwave Spectrum, Dipole Moment, and Structure of Bicyclo[1.1.0]butane." Journal of the American Chemical Society. 88, 5049-5050 (1966) 10.1021/ja00973a066
1969Cox/Har:1976 Cox, Harmony, Nelson, Wiberg, Microwave Spectrum and Stucture of Bicyclo[1.1.0]butane, J. of Chem. Phys., Vol. 50, #5, pgs. 1976-1980 10.1063/1.1671318

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