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The energy levels of the ideal divacancy states in band gap for more than 10 cubic semiconductors are invesgated by using the basic equations given in ref. [1] and the tight binding Hamiltonian given by vogl et al. A simple physical model is used to describe the basic physics of the divacancy problem.

A complete set of equations for determining the energy levels and the wavefunc-tions with different symmetry of electronic states of the ideal divacancy in cubic semiconductors is obtained using the Koster-Slater Green's function method. Using an empirical tight binding Hamiltonian for the band structure of the host and the on-site pertubation approximation for the defect, only the on-site and the off-site Green's functions of the host and their derivatives with respect to energy E are involved in these equations.

The wavefunctions of the Eu, state and the Eg state are evaluated for the ideal divacancy in Si, using the basic equations given in [1] and the tight binding Hamiltonian given by P. Vogl et al. Comparison between the culculated results and the ESR and ENDOR spectra of V2+ and V2- in Si is discussed.

The wavefunctions of the A1 and E states of the ideal divacancy in GaAs, GaP are calculated using the basic equations given in ref. [1] and the tight-binding Hamiltonian given by P. Vogl et al. It is shown that the largest part of the wavefunctions of divacancy states is on the three nearest Ga atoms of the As or P vacancy, the rest part of the wavefunction decreases slowly and non-monotonically as the distance from the defect increases.