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
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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 C4H4N2O2 (Uracil)

No experimental rotational constants available.
Calculated rotational constants for C4H4N2O2 (Uracil).

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
rCN 1.371 6 7 1967Ste:1102
rCN 1.376 3 7 1967Ste:1102
rCN 1.371 1 3 1967Ste:1102
rCC 1.430 1 2 1967Ste:1102
rCC 1.340 1 4 1967Ste:1102
rCN 1.358 4 6 1967Ste:1102
rCO 1.215 1 5 1967Ste:1102
rCO 1.245 1 5 1967Ste:1102
rHC 0.931 2 9 1967Ste:1102
rHN 0.836 6 12 1967Ste:1102
rHC 0.957 4 11 1967Ste:1102
rHN 0.877 3 10 1967Ste:1102
aNCN 114 3 7 6 1967Ste:1102
aCNC 126.7 1 3 7 1967Ste:1102
aCCN 115.5 2 1 3 1967Ste:1102
aCCC 118.9 1 2 4 1967Ste:1102
picture of Uracil

Bond descriptions

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

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)


Calculated geometries for C4H4N2O2 (Uracil).
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