Lattice dynamics, elasticity and magnetic abnormality in ordered crystalline alloys Fe 3 Pt at high pressures
Lattice dynamics, elasticity and magnetic abnormality in ordered crystalline alloys Fe 3 Pt at high pressures
复制标题
高压下有序晶体合金 Fe 3 Pt 的晶格动力学、弹性和磁性异常
DOI：
10.1016/j.jmmm.2018.01.008
复制
发表时间：
2018
影响因子：
2.7
通讯作者：
Lin Li
中科院分区：
文献类型：
--
作者：
Tai;Guo;Yong Su;C. Ge;Xinxin Zhang;Lin Zhu;Lin Li
The ordered crystalline Invar alloy Fe3Pt is in a special magnetic critical state, under which the lattice dynamic stability of the system is extremely sensitive to external pressures. We studied the pressure dependence of enthalpy and magnetism of Fe3Pt in different crystalline alloys by using the first-principles projector augmented-wave method based on the density functional theory. Results show that theP4/mbmstructure is the ground state structure and is more stable relative to other structures at pressures below 18.54 GPa. The total magnetic moments of L12,I4/mmmand DO22structures decrease rapidly with pressure and oscillate near the ferromagnetic collapse critical pressure. At the pressure of 43 GPa, the ferrimagnetic property in DO22structure becomes apparently strengthened and its volume increases rapidly. The lattice dynamics calculation for L12structures at high pressures shows that the spontaneous magnetization of the system in ferromagnetic states induces the softening of the transverse acoustic phonon TA1 (M), and there exists a strong spontaneous volume magnetostriction at pressures below 26.95 GPa. Especially, the lattice dynamics stability is sensitive to pressure, in the pressure range between the ferromagnetic collapse critical pressure (41.9 GPa) and the magnetism completely disappearing pressure (57.25 GPa), and near the pressure of phase transition from L12toP4/mbmstructure (27.27 GPa). Moreover, the instability of magnetic structure leads to a prominent elastic modulus oscillation, and the spin polarizability of electrons near the Fermi level is very sensitive to pressures in that the pressure range. The pressure induces the stability of the phonon spectra of the system at pressures above 57.25 GPa.
影响因子：
3.7
作者：
Togo, Atsushi;Oba, Fumiyasu;Tanaka, Isao
通讯作者：
Tanaka, Isao