National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
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XIVReaction data
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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
rCH 0.931 2 9 1967Ste:1102
rNH 0.836 6 12 1967Ste:1102
rCH 0.957 4 11 1967Ste:1102
rNH 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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squib reference DOI
1967Ste:1102 RF Stewart "REDETERMINATION OF CRYSTAL STRUCTURE OF URACIL" Acta Cryst. 23, 1102, 1967 10.1107/S0365110X67004360

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