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Calculated Ionization Energy for HNO2 (Nitrous acid)

20 09 09 14 00
Experimental Ionization Energy is 11.3 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.
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Ionization Energies in eV
Methods with predefined basis sets
composite G4 10.947

Ionization Energies in eV
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ
hartree fock HF     9.974           10.015       9.932
density functional BLYP     10.429                    
B3LYP                 10.898        
B3LYPultrafine                       10.866  
M06-2X   10.983 10.817                    
PBE1PBE     10.564                    
HSEh1PBE 10.724   10.564 10.783             10.587    
TPSSh     10.524 10.741     10.375       10.555    
wB97X-D   10.828 10.714 10.916   10.738     10.783 10.916 10.665 10.735  
B97D3 10.652   10.506 10.764   10.580   10.677 10.698   10.560 10.667  
3-21G 3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ
Moller Plesset perturbation MP2     10.741   10.661       10.879        
MP3=FULL     10.720 10.951                  
B2PLYP     10.558               10.676    
3-21G 3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ

Ionization Energies in eV
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF                 9.915
density functional B3LYP                 10.814
PBEPBE                 10.581
Moller Plesset perturbation MP2                 10.975
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.