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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   18  
Energy 298.15K   2  
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   20  
HOMO-LUMO Energies HOMO energies   20  
Barriers to Internal Rotation internal rotation  0 
Geometries Cartesians  20  
Internal Coordinates bond lengths bond angles  20 
Products of moments of inertia moments of inertia  18 
Rotational Constants rotational constants  19 
Point Group  21 
Vibrations Vibrational Frequencies vibrations x19x
Vibrational Intensities  19 
Zero-point energies  19 
Vibrational scaling factors  
Anharmonic frequencies and constants      
Electronic States Electronic states x 0  
Electrostatics Atom charges   11  
Dipole dipole  9 
Quadrupole quadrupole  11 
Polarizability polarizability  11 
Other results Spin   0  
Number of basis functions   6  
Diagnostics   0  
Conformations   2 x