First-principles studies of n-type and p-type doping in hematite $\alpha$-Fe$_{2}$O$_{3}$*

Spin-polarized density functional theory calculations are conducted to study the substitutional anionic doping in hematite $\alpha$-Fe$_{2}$O$_{3}$ crystal. Selective Group V and VII impurities, as p-type and n-type dopants, respectively, are investigated. The formation energies are lower under Fe-rich environment in general. The impurity levels are discussed both by the transition levels of the formation energies and the single-particle levels. And the local magnetic structure around an impurity is also analyzed.