First-principles calculations for structural phase transition of LixFeS2 Original Research Article

We investigated the crystal structure of LixFeS2 with varying the amount of Li in the range of 1⩽x⩽2 by first-principles theoretical calculations, in order to clarify its structural change and phase stability. We verified the structural phase transition around x=1.5, which was suggested by experiments. In addition, we proposed the crystal structure of LixFeS2 in 1⩽x⩽1.5 for the first time. Furthermore, the sudden change of the electronic conductivity observed around x=1.5 is properly explained with the change of the electronic band structure.