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采用第一原理方法,基于ultrasoft赝势、密度函数理论,从原子层面对纯γ-Mn的顺磁、铁磁和反铁磁性状态下的电子、基态属性、相稳定和磁有序结构进行了研究.通过自旋极化分析讨论了纯γ-Mn这3种磁性状态的结构稳定性,发现在基态时,反铁磁性状态的γ-Mn结构最稳定,且Mn原子处于高自旋状态,其理论磁通量为2.41μB/atom,这与实验结果吻合通过局部状态密度(DOS),分析了它们的键和磁有序特性,发现主要是位于Fermi态附近的3d轨道电子对磁性起决定性的作用,其向上自旋和向下自旋的主峰分别处于Fermi能下面的键区和Fermi能上面的反键区.通过比较这3种磁性状态可知,反铁磁的γ-Mn存在显著的磁体积效果.
Based on the ultrasoft pseudopotential and density function theory, the first principle method was used to study the electron, ground state, phase stability and magnetic ordered structure of the pure γ-Mn in the paramagnetic, ferromagnetic and antiferromagnetic states from the atomic level The structure stability of the pure γ-Mn magnetic states was discussed by spin-polarization analysis. It was found that the γ-Mn structure of the anti-ferromagnetic state is the most stable and the Mn atom is in a high-spin state at the ground state. The theory The magnetic flux is 2.41μB / atom, which agrees well with the experimental results. Through the DOS, the bond and magnetic ordering properties are analyzed. It is found that the 3d orbital electrons located mainly in the Fermi state play a crucial role in the magnetism. The main peaks of spin-up and spin-down are respectively in the bond pad beneath Fermi energy and in the antibonding region above Fermi energy. By comparing these three magnetic states, it can be seen that the antiferromagnetic γ-Mn exhibits significant magnetic volume effect.