THE PSEUDOPOTENTIAL APPROACH TO THE SHALLOW DONOR PROBLEM IN II-VI SEMICONDUCTORS

The problem of chemical shift of shallow donor states in compound semiconductors is investigated in the framework of pseudopotential theory. The 'first principle' pseudo-Hamiltonian including the electron-phonon interaction for shallow donor is obtained and the one-band pseudo effective mass approximation is discussed. As an example the ionization energies for several donors in CdS and ZnSe are calculated. A good correspondence between the theory and experimental data for impurities in cation site is found.