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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
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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 C4H6S (Thiophene, 2,5-dihydro-)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.22087 0.16006 0.09624
Rotational Constants from 1981Dur/Li:1564
Calculated rotational constants for C4H6S (Thiophene, 2,5-dihydro-).

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 1.095 2 6 1981Dur/Li:1564 in CH2
rCH 1.085 4 10 1981Dur/Li:1564
rCC 1.340 4 5 1981Dur/Li:1564
rCC 1.518 2 4 1981Dur/Li:1564
rCS 1.816 1 2 1981Dur/Li:1564
aHCH 109.8 6 2 7 1981Dur/Li:1564
aCCC 116.75 2 4 5 1981Dur/Li:1564 adjusted from listed value of 116.5 to get C=C bond length to agree with listed 1.34
aCCS 105 1 2 4 1981Dur/Li:1564 adjusted from listed value of 106.25 to get C=C bond distance to agree with listed value of 1.34
aCSC 96.5 2 1 3 1981Dur/Li:1564
aHCC 121.75 5 4 10 1981Dur/Li:1564
picture of Thiophene, 2,5-dihydro-

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
S1 0.0000 0.0000 1.2290
C2 0.0000 1.3548 0.0197
C3 0.0000 -1.3548 0.0197
C4 0.0000 0.6716 -1.3358
C5 0.0000 -0.6716 -1.3358
H6 -0.8945 1.9701 0.1628
H7 0.8945 1.9701 0.1628
H8 0.8945 -1.9701 0.1628
H9 -0.8945 -1.9701 0.1628
H10 0.0000 1.2393 -2.2605
H11 0.0000 -1.2393 -2.2605

Atom - Atom Distances (Å)

  S1 C2 C3 C4 C5 H6 H7 H8 H9 H10 H11

Calculated geometries for C4H6S (Thiophene, 2,5-dihydro-).
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squib reference DOI
1981Dur/Li:1564 During, Li, During, Spectra and structure of small ring compounds. XLII. Microwave spectrum of 2,5-dihydrothiphene, J. Chem., Phys., Vol. 74, #3, pgs. 1564-1567 10.1063/1.441297

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