The electronic structure, atomic geometry, and formation energy of native point defects of Si or Fe in β-FeSi2 were investigated by using first principle pseudopotential calculations based on the generalized gradient approximation density function theory. The formation energies of the native point defects depended largely upon the atomic chemical potentials of Fe and Si. Mulliken population analysis revealed that electron transfer occurred from Si to Fe by introducing defects of Si or Fe. The density of states calculation predicted that the crystal with Si vacancies indicated p-type and that with Fe vacancies indicated n-type, which was in good agreement with previously reported experimental results.

First-Principles Study of Native Point Defects in β-FeSi2. J.Tani, H.Kido: Journal of Alloys and Compounds, 2003, 352[1-2], 153-7