Atomic and magnetic order in the shape memory alloy Mn2NiGa
Atomic and magnetic order in the shape memory alloy Mn2NiGa
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DOI：
10.1088/0953-8984/22/50/506001
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发表时间：
2010-12-22
影响因子：
2.7
通讯作者：
Ziebeck, K. R. A.
中科院分区：
文献类型：
--
作者：
Brown, P. J.;Kanomata, T.;Ziebeck, K. R. A.
磁性形状记忆合金Mn_2NiGa的磁化强度和高分辨中子粉末衍射测量证实它是铁磁性的，居里温度高于500 K。该化合物经历了类似于90 K的宽结构相变Δ T，平均相变温度T-M类似于270 K。高温母相为立方相（α = 5.937埃），具有改进的L2（1）结构。在500 K时，基本上全部在4a位上的有序磁矩为1.35 μ B/Mn。低温马氏体具有空间群I4/mmm，并且通过贝恩变换a（泰特）=（a（cuB）+ B（cuB））/2、B（泰特）=（a（cuB）- B（cuB））和c（泰特）= c（cuB）与立方相相关，其中晶胞体积的变化是
Magnetization and high resolution neutron powder diffraction measurements on the magnetic shape memory alloy Mn2NiGa have confirmed that it is ferromagnetic with a Curie temperature above 500 K. The compound undergoes a broad structural phase transformation Delta T similar to 90 K with a mean transition temperature T-M similar to 270 K. The high temperature parent phase is cubic (a = 5.937 angstrom) and has a modified L2(1) structure. At 500 K the ordered magnetic moment essentially all on the 4a site is 1.35 mu B/Mn. The low temperature martensite has space group I4/mmm and is related to the cubic phase through a Bain transformation a(tet) = (a(cub) + b(cub))/2, b(tet) = (a(cub) - b(cub)) and c(tet) = c(cub) in which the change in cell volume is