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

All data (experiment and calculated) in the CCCBDB for C4H4 (cyclobutadiene)

INChI
InChI=1S/C4H4/c1-2-4-3-1/h1-4H

An "x" indicates that data is available. A number indicates how many calculations have been completed.
Property Experiment Calculated Comparison
Energies
Entropies
Enthalpy 298.15K enthalpy of formation      
Enthalpy 0K enthalpy of formation      
Energy 0K   350  
Energy 298.15K   12  
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 x0x
Nuclear Repulsion Energy   351  
HOMO-LUMO Energies HOMO energies   348  
Barriers to Internal Rotation internal rotation  0 
Geometries Cartesians  348  
Internal Coordinates bond lengths bond angles  348 
Products of moments of inertia moments of inertia  333 
Rotational Constants rotational constants  343 
Point Group  352 
Vibrations Vibrational Frequencies vibrations x341x
Vibrational Intensities  313 
Zero-point energies  341 
Vibrational scaling factors  
Anharmonic frequencies and constants      
Electronic States Electronic states x 0  
Electrostatics Atom charges   202  
Dipole dipole  268 
Quadrupole quadrupole  236 
Polarizability polarizability  200 
Other results Spin   0  
Number of basis functions   33  
Diagnostics   0  
Conformations   2 x