Interaction energy general asymptotic form

Apart from their asymptotic form for 0 < /3 < a%—a (Equations 2.20 and 2.23 in Section 2.1), the general expressions for the orbital interaction energies of the heteropolar MOs are rather complicated in the case of nonorthogonal AOs. For the sake of simplicity, we shall content ourselves with the simpler expressions occurring in the case of orthogonality between the interacting AOs Xi and 2 Under this assumption, Equations (2.58) simplify to ... 

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