Study the electronic properties and magnetization of rutile polymorph CoxTi1-xO2 super cell at various cobalt (Co) concentrations using first principle calculation

First principle calculation has been performed to study the electronic properties and magnetization of CoxTi1-xO2 at different cobalt concentration. Equilibrium lattice constant of CoxTi1-xO2 at 0.0% cobalt concentration was obtained about 4.81 angstrom. The obtained value is slightly larger than the experimental value. The calculated band gap of CoxTi1-xO2 at 0.0% cobalt concentration is 3.0 eV which consistent with other reports. The calculated band gap for 16.6% is 0.5 eV, for 33.3% is 0.1 eV and for 50.0% is approximately 0.0 eV. The calculated band gap of CoxTi1-xO2 decreased with increased cobalt concentration. On the other hand at 0.0% cobalt concentration, the magnetization is zero and at 50.0% cobalt concentration, magnetization is 3.36 Bohr mag/cell. The density of states calculation for spins up and spins down are symmetric at 16.6% and 33.3% cobalt concentration. At 50.0% cobalt concentration the density of states shows asymmetric for spin up and spin down which indicates the ferromagnetic nature. (C) 2018 Elsevier B.V. All rights reserved.