Structural phase stability in Ni2.17Mn0.83Ga film

Abstract

Ni2.17Mn0.83 Ga transforms between a cubic structure and a coexistent state of an orthorhombic and a monoclinic structure. The electronic structures of Ni2.17Mn0.83Ga and Ni2MnGa were calculated for thin films to investigate the influence of excess nickel and the effect of the surface on the phase stability. The total energy and band energy were also calculated to examine the role of the each constituent atoms in file structural stability. It is theoretically predicted that the Ni2.17Mn0.83Ga film preserve the shape memory property like the bulk states and that the excess nickel atoms contribute largely to the stability of the monoclinic structure.