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Calculated Ionization Energy for C2H2O2 (Ethanedial)

Experimental Ionization Energy is 10.2 eV
Please note! These calculated ionizataion energies have the vibrational zero-point energy (zpe) included, but the zpe has NOT been scaled. Click on an entry for more details, including the ionization energy with a scaled zpe.
Original data displayed. Press to display differences.
Differences displayed. Press to display original data.

Ionization Energies in eV
Methods with predefined basis sets
semi-empirical PM6  

Ionization Energies in eV
Methods with standard basis sets
3-21G 6-31G* 6-31+G** TZVP cc-pVTZ
hartree fock HF       9.494  
density functional SVWN 10.067 10.195 10.445    
B3LYP       9.970  
M06-2X   9.993      
PBE1PBE   9.854      
HSEh1PBE   9.846      
Moller Plesset perturbation MP2       9.911  
B2PLYP   9.694     9.819
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.