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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I.B.3. (II.A.2.)

All data (experiment and calculated) in the CCCBDB for C4H4N2O2 (Uracil)

Other names
2,4(1H,3H)-Pyrimidinedione; Pirod; Pyrod; Ura; 2,4-Dihydroxypyrimidine; 2,4-Dioxopyrimidine; 2,4-Pyrimidinediol; 2,4-Pyrimidinedione; 2,6-Dihydroxypyrimidine; 1H-Pyrimidine-2,4-dione; 2,(1H,3H)-Pyriminedione; 2,4-Dioxypyrimidine; 4-Hydroxy-2(1H)-pyrimidinone; pyrimidine-2,4(1H,3H)-dione;

An "x" indicates that data is available. A number indicates how many calculations have been completed.
Property Experiment Calculated Comparison
Enthalpy 298.15K enthalpy of formation      
Enthalpy 0K enthalpy of formation      
Energy 0K   23  
Energy 298.15K   1  
Atomization Enthalpy 298.15K  0 
Atomization Enthalpy 0K  0 
Entropy (298.15K) entropy  0 
Entropy at any temperature   0  
Integrated Heat Capacity integrated heat capacity  0 
Heat Capacity (Cp) Heat capacity  0 
Nuclear Repulsion Energy   22  
HOMO-LUMO Energies HOMO energies   23  
Barriers to Internal Rotation internal rotation  0 
Geometries Cartesians  23  
Internal Coordinates bond lengths bond angles x23x
Products of moments of inertia moments of inertia  22 
Rotational Constants rotational constants  23 
Point Group  24 
Vibrations Vibrational Frequencies vibrations  690 
Vibrational Intensities  23 
Zero-point energies  23 
Vibrational scaling factors  
Anharmonic frequencies and constants      
Electronic States Electronic states   0  
Electrostatics Atom charges   14  
Dipole dipole  18 
Quadrupole quadrupole  14 
Polarizability polarizability  17 
Other results Spin   0  
Number of basis functions   2  
Conformations   1  
2015 06 10 17:36