Exchange and magnetic order in bulk and nanostructured Fe 5 Si 3
Exchange and magnetic order in bulk and nanostructured Fe 5 Si 3
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块状和纳米结构 Fe 5 Si 3 中的交换和磁序
DOI：
10.1016/j.jmmm.2018.02.015
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发表时间：
2018
影响因子：
2.7
通讯作者：
Sellmyer, D.J.
中科院分区：
文献类型：
--
作者：
Skomski, R.;Kumar, P.;Balamurugan, B.;Das, B.;Manchanda, P.;Raghani, P.;Kashyap, A.;Sellmyer, D.J.
通过实验、密度泛函模拟和多体模型计算研究了块体和纳米结构 Fe5Si3 的居里温度。以六方 D88 结构结晶的块状金属间化合物表现出几个有趣的特征：它不以室温平衡相存在，接近铁磁性的开始，并表现出两个晶体学上非常不同的 Fe 位点。通过快速淬火（块体）和簇沉积（纳米颗粒薄膜）制备的样品，居里温度约为 400K。使用 Kohn-Korringa-Rostoker (KKR) 方法计算原子间交换常数，并用于解决系统的多亚晶格平均场问题。采用 Viennaab 初始模拟包 (VASP) 研究 Fe 矩对热致自旋失准的依赖性，并通过模型计算得出量子自旋液体校正的估计值。该理论包括海森堡交换，但高估了居里温度，并讨论了处理弱铁磁多亚晶格金属间化合物的其他方法。
The Curie temperature of bulk and nanostructured Fe5Si3is investigated using experiments, density-functional simulations, and many-body model calculations. The bulk intermetallic, which crystallizes in the hexagonal D88structure, exhibits several intriguing features: it does not exist as a room-temperature equilibrium phase, is close to the onset of ferromagnetism, and exhibits two crystallographically very different Fe sites. The samples, produced by rapid quenching (bulk) and cluster deposition (nanoparticulate thin films), have Curie temperatures of about 400 K. Interatomic exchange constants are calculated using the Kohn-Korringa-Rostoker (KKR) method and used to solve the multisublattice mean-field problem for the system. The Viennaab initiosimulation package (VASP) is employed to study the dependence of the Fe moment on the thermally induced spin misalignment, and a model calculation yields an estimate for quantum-spin-liquid corrections. The theory includes Heisenberg exchange but overestimates the Curie temperature, and a discussion is given regarding additional approaches to handle weakly ferromagnetic multisublattice intermetallic compounds.