ABSTRACT
The electronic and magnetic properties of Fe3Pt under high pressures had been studied by the CASTEP codes. Both cubic and tetragonal phases have been investigated under high pressures up to 8GPa, and the magnetic and non-magnetic states were compared. In the case of cubic, ferromagnetic phases, the linear compression rate is 1.39×10−3/GPa. As pressure increases, s band population increases while p band population decreases, and d band population increases. The magnetic moment of Fe atoms decreases while that of Pt atoms increases. The cell moment increase and the saturated magnetization decreases. Calculations performed on tetragonal phases show that the cell volumes and magnetizations are smaller than those of the corresponding cubic phases; but the total energies are almost the same. Two phases with different cell volume and magnetization could exist in Fe3Pt. The results on non magnetic phase showed a small cell volume and high total energy, indicating that the ferromagnetic state is the ground state of Fe3Pt. Geometry optimization of non magnetic tetragonal phase yield the same values for a and c, such reduced to the cubic phase. It shows that the cubic to tetragonal martensitic transformation could not exist.
