Electronic calculations on theMgTiOBO3warwickite: A real-space renormalization approach

Electronic properties of a warwickite, ${\mathrm{MgTiOBO}}_3$, are calculated within the Green’s functions formalism, taking into account the crystallographic structure of the system and using a multiorbital basis to represent the Hamiltonian. The many body problem is considered through an alloy analog approximation for the intra-atomic interaction at the titanium sites by using real-space renormalization techniques. Local and total density of states reflect the one-dimensional character of the structure and its insulating nature. The metal-nonmetal transition is also analyzed as a function of the charge doping.