Half-metallic behaviour in doped TiO2 (rutile) with double impurities: ab initio calculation

Dilute magnetic oxides are without doubt among the most interesting classes of magnetic materials. However, the nature of their electronic structure and magnetic exchange is far from understood. Here, we apply the ab initio augmented spherical wave (ASW) method, with corrected generalised gradient approximation to study the electronic structure and magnetic properties of doped TiO2 rutile with double impurities. The study reveals a half-metallic ferromagnetic behaviour for Ti1-2xCrxMoxO2, and the local magnetic moments of the impurities and their oxidation states agree with the charge transfer between Cr and Mo, which would lead to the ferromagnetic state through the double-exchange mechanism in transition metal oxides.