Band Structure of a New (16-18 K) Superconductor LiFeAs Compared to Li0.5FeAs and LiCoAs

The hand structure of a new (16-18 K) superconductor LiFeAs, as a possible first representative of the third (the so-called 111) group of phases, which along with the groups of four-component 1111 oxyarsenides LnOFeAs and three-component 122 arsenides AFe(2)As(2), belong, to the family of new high-temperature (26-56 K) FeAs superconductors, has been studied using the ab initio full-potential augmented-plane-wave method and the generalized-gradient approximation. The structure, energy bands, densities of state, Fermi surface, low-temperature electron specific heat gamma, and molar Pauli magnetic susceptibility for LiFeAs are discussed and compared to similar data tor the systems simulating the hole (Li0.5FeAs) and electron (LiCoAs) doping of LiFeAs.