First-principles DFT study new series of ruthenates double perovskites Ba2MRuO6 with M = Sc, Ti, V, Cr, Mn, Fe and Co

First-principles density functional theory (DFT) within generalized gradient approximation (GGA) and GGA incorporated with Coulomb correlation interaction U (GGA + U) are used to investigate the crystal, electronic, magnetic and optical properties of a new series containing barium-ruthenates double perovskites Ba2MRuO6, with M is being 3d transition-metal ion (M = Sc, Ti, V, Cr, Mn, Fe and Co). All these compounds crystallize in a cubic structure at room-temperature fitting in space-group Fm-3m, with a = b = c approximate to 2a(0) (a(0) = 4 angstrom). Ba2MRuO6 oxides show a long-range antiferromagnetic superexchange interaction between neighboring 3d and 4d ions achieved via M3+ (3d(n)) up arrow O2-(2p(6))-Ru5+ (4d(3)) down arrow. Metallic state exists in Ba2MRuO6 within GGA for M = Sc, Ti, V, Mn, Fe and Co, and semimetallic exists in M = Cr case. While, GGA + U produces half-metallic (HM) state in M = Ti, V, Mn and Co, and insulating state in M = Sc, Cr and Fe cases. In the rest of the paper, total and partial density of states, magnetic moments, bond-valence sums, charge transfer in double perovskites Ba2MRuO6 are computed and discussed in detail. In addition, the real and imaginary parts of the optical dielectric function and energy loss spectra are computed and the main features shown by their spectra are ascertained on the base of the investigation of density of states. (C) 2017 Elsevier B.V. All rights reserved.