Simulation fo Dynamical Bond Charge Transfer Properties in Elemental Semiconductors by Means of a Simple Quantum‐Mechanical Model

Abstract

AbstractA simple model is presented, that constructs the valence charge density of monoatomic semiconductors by linear superposition of appropriate diatomic molecules including the bond charges between next neighbour atoms. By means of this model the study of dynamical density properties is possible being in general calculated by full self‐consistent pseudopotential schemes. An essential feature of that density variation is the bond charge transfer, which will be analyzed with respect to the variation of the next neighbour distance and the bond angle. During stretching or compressing of the next neighbour distance the variation in the |s〉 portion of the valence orbitals has to be taken into account. Using the results for silicon, which are fitted to the self‐consistent outcome and to experimental data, an estimation of the transfer constants of other group‐IV elemental crystals is given. The model can be applied to the interpretation of dynamical bond charge transfer influenced experiments, like pressure and temperature dependence of the “forbidden” X‐ray reflection power.