Point-defects in magnesium sulfide

The results of a study of point defects in MgS are presented. First we obtain empirical interionic potentials in the framework of a shell model and then calculate defect energies using the HADES and ICECAP simulation procedures. The calculated Schottky formation energy is 10.9 eV in comparison to the cation and anion Frenkel formation energies of 11.9 and 25.1 eV, respectively. The migration energy by the vacancy mechanism of the Mg²⁺ and S²⁻ ions is predicted to be 2.5 and 3.4 eV, respectively. One-electron ICECAP calculations yield the optical absorption energy of 3.1 eV for the F⁺ center in MgS.