First principles study of “111” type iron arsenide superconductors

First principles calculations are performed using Tight-binding LMTO method with Local density approximation (LDA) and Atomic sphere approximation (ASA) to understand the electronic properties of of iron arsenide compounds. The estimated superconducting transition temperature (Tc) for LiFeAs and NaFeAs are ∼18K, ∼26K respectively and is in agreement with the experimental value. The pressure dependence of superconducting transition temperature is also investigated.