Modeling and Simulation of Physical Properties in Semiconductors

The empirical concepts as electronegativity, ionicity and bulk modulus are very important for studying the basic properties of solids. The difficulty in defining the ionicity and bulk modulus lies in transforming a qualitative or verbal concept into a quantitative, mathematical formula. My works concentrated on using empirical pseudopotential method (EPM) to calculate electronic properties (ionicity factor) i in terms of the difference between the first and second valence band at point X, Eg (V2-V1), and making various formulas as a function of transverse effective charge eT*, nearest-neighbor distance d, cohesive energy Ecoh, and refractive index n0. I had investigated for the structural properties (bulk modulus) B0 new models in terms of the cation part SC of the charge density, the transition pressure Pt and the lattice parameter. This study has three essential goals: 1. Define the ionicity factor and the bulk modulus by the electronic band structure and charge density, respectively. 2. Establish a new scale. 3. Study the validity of the new models under external effects. The reasonable results compared with experimental and theoretical ones are obtained.