Investigations of properties of Fe-Ga alloys from ab initio calculations

In this paper the results of a study of crystal structure and magnetic properties of Fe$_{1-x}$Ga$_x$ ($x = 0.0$–$0.30$) alloys obtained using the density functional theory, taking into account the various approximations of the exchange-correlation energy are presented. Based on calculations of equilibrium energy for the phases A2, D0$_3$, and L1$_2$ the phase diagram of the alloys Fe$_{1-x}$Ga$_x$ is constructed. It was shown, that on this diagram the sequences of the phase transitions for 0.25 and 0.27 Ga concentration allows us to describe experimentally observed sequences of phase transitions.