CAS SCF and contracted CI calculations on the HO3 radical

CAS SCF and CCI calculations have been performed in order to establish the existence or non-existence of the HO₃ radical. The potential surface for the dissociation reaction, HO₃ → O₂(³Σ) + OH, along one chosen coordinate has been calculated. The calculations show that although the wavefunctions describing the short-distance and long-distance states are of different character, the energies are the same and the curve connecting the states is very flat. There is probably no barrier towards dissociation of the radical. However, the existence of HO₃ can still not be excluded.