Pressure-induced phase transformations of LiGaO2: First principles study

Abstract

Phase transformations of β-LiGaO2 (Pna21) under different pressure conditions are studied using first principles calculations. Under specific conditions, LGO can exist in various structures some of which have not been previously reported (oP16 and P41212). Under sufficiently strong hydrostatic pressure, LGO can transform into a rocksalt-like structure. Under strong uniaxial stress LGO can transform into a tetragonal structure or an orthorhombic structure depending on the orientation of the applied stress. The stability of different crystal structures under different applied stresses and the phase transformation processes are studied by calculating the enthalpy surfaces and transformation barriers under different stresses.