First-principles comparison of the cubic and tetragonal phases of

Using ab initio density functional based methods, we study the normal metal state properties of the ∼3 K Mo 3 Sb 7 superconductor, in its high temperature cubic and low temperature tetragonal structures. Although the density of states at the Fermi energy is reasonably high in both structures, our calculations unequivocally show that there exists no long range magnetic ordering in this system. We also address the optical properties of the compound. The magnetism in Mo 3 Sb 7 is studied by fixed spin moment calculations, which yield a shallow non-magnetic minimum, thus inferring propensity to a magnetic instability.