Molecular Orbital Calculation with The Extended Huckel Method for H_2 O_2 Molecule

We investigated the electronic structure or H_2 O_2 molecule using the extended Huckel method. The exchange integrals H__ have been evaluated by using the Cusachs' approximation. The caluculation has been carried out with the bond lengths and the O- O-H angle fixed to the experimental data and the dihedral angle used as the only parameter. The equilibrium dihedral angle, obtained as the result, almost coincide with the observed value, but the result for the electron population bas como out poor. We infer that the Cusachs type exchange integral gives fairly good result for small overlapping S_ and rather poor rerult for large S_