典型锰基化合物磁交换相互作用的中子衍射研究

项目名称： 典型锰基化合物磁交换相互作用的中子衍射研究

项目编号： No.11275013

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 杜红林

作者单位： 北京大学

项目金额： 88万元

中文摘要： 本项目配合中国先进研究堆、散裂中子源两大科学平台建设，适应我国中子散射技术发展的迫切需求，拟用中子衍射为主要手段研究具有代表性的(Mn,Fe)2-xX和R(Mn,M)12(其中X=Sn,Sb,Ge等，R为稀土元素，M=Fe,Al,Mo等）两系列Mn基化合物的磁相互作用机理。采用熔炼、速凝和甩带等方式及最佳热处理工艺，制备出高质量的具有重要研究价值的化合物，通过变温、高压、磁场下的高强度和高分辨中子衍射，系统研究晶体结构、磁结构及其随温度变化规律，结合磁性测量和第一性原理计算，从理论上分析磁相互作用机理。研究有助于：推动中子衍射技术在我国的应用和发展，积累技术，培养人才；了解3d过渡族元素磁相互作用的本质，为磁学理论的发展做出贡献，并为进一步改善磁性能提供理论指导；发现具有良好应用前景的室温磁制冷材料等磁相关效应材料。

中文关键词： 磁性材料；磁相互作用；磁相关效应；中子衍射；结构分析

英文摘要： This proposal meets the construction of the two scientifical platforms CARR and CSNS, and the requirements of developing national neutron scattering. The mechanisms of exchange interaction of (Mn,Fe)2-xX and R(Mn,M)12(X=Sn,Sb,Ge etc， R=rare earth elelments，M=Fe,Al,Mo etc）serial compounds of representative Mn-based compounds will be studied using neutron diffranction technique as the main method.To obtain the samples of high quality,we will try arc-melting,strip-casting,melt-spinning etc and search for the best heat treatment process. Neutron diffraction patterns will be collected in various environments such as different temperatures, pressures and magnetic fields,with which the relationship between the crystal structure and the magentic structure and the evolutive rules will be studied systematically.The ab-initio calculations will also be conducted as another aspect to analyse the interaction mechanisms. The reasearch can not only expand the knowledge of the interactions of transition-metal elements which limits the improvement of the performance of the materials and discovery several potential candidates for room-temperature refrigeration,but also promote the technology of neutron diffraction and the talent-training in the correlative fields.

英文关键词： Magnetic materials；Magnetic exchange interaction；Magnetic related effects；Neuton diffraction；Structure analyses