Quantum chemical simulations of bound hold polarons (V Mg centers) in corundum crystals

摘要

Abstract: The semi-empirical INDO method has been applied to the calculations of the bound hole small-radius polarons in corundum. Results for optimized atomic and electronic structure using two different approaches (molecular cluster and periodic, supercell model) are critically compared. Both models find that two-site configurations of bound hole polarons have the lowest energy (which does not exclude existence of one-site polarons also characterized by essential relaxation energies). Experimental ENDOR data on V$-Mg$/ defects are discussed in the light of the calculations. !25