MODEL PSEUDOPOTENTIAL CALCULATIONS FOR THE ELECTRONIC STRUCTURE OF Si, Ge, AND GaAs

This paper describes a nonlocal model pseudopotential proposed for the description of the electron-ion interaction in metals. In a series of works the present model pseudopotential was used to calculate the properties of simple, transitional and rare earth metals. In all cases, a good agreement of calculation results with appropriate experimental data was obtained. When we determined the parameters of the pseudopotential for energy eigenvalues we use energy of the observed spectroscopic terms of the free ion. We have used parameters of model pseudopotential in our present semiconductor calculations. When constructing the model pseudopotentials for semiconductors we substitute metallic dielectric permittivity function for the corresponding function in Penn's approximation. Spin -orbit contributions have not been included in the present calculations. The band energy structure calculations have been performed for semiconductors Si, Ge, and GaAs. The band structure parameters obtained in the present work demonstrate a good agreement with experimental values and results of other calculations. We conclude that the proposed screened model pseudopotential can be used for the calculation of band energy spectrum of simple semiconductor structures and can be effectively extended to adequately describe the energy spectrum of systems with a large number of atoms in the unit cell. This approach is motivated by the demand for pseudopotentials able to address semiconductor heterostructures and nanostructures where ab initio methods are both too costly and insufficiently accurate at the level of the local density approximation.