Possible superconductivity in Fe-Sb based materials: Density functional study of LiFeSb

We investigate the electronic and other properties of the hypothetical compound LiFeSb in relation to superconducting LiFeAs and FeSe using density-functional calculations. The results show that LiFeSb in the LiFeAs structure would be dynamically stable in the sense of having no unstable phonon modes and would have very similar electronic and magnetic properties to the layered Fe-based superconductors. Importantly, a very similar structure for the Fermi surface and a spin-density wave related to but stronger than that in the corresponding As compound is found. These results are indicative of possible superconductivity analogous to the Fe-As based compounds if the spin-density wave can be suppressed by doping or other means. Prospects for synthesizing this material in pure form or in solid solution with FeTe are discussed.