单相多铁性体CaMn_7O_(12)的理论研究与固相合成  

Theoretical Calculations and Solid-Phase Synthesis of the Single Phase Multiferroic CaMn_7O_(12)

作　　者：张瑞浩[1] 代建清[1] 牛之慧 李亚[1] 程振宇[1] 王志翔[1] 

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093

出　　处：《无机化学学报》2016年第5期762-768,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.51162019;51462019)资助项目

摘　　要：在理论研究方面,采用基于密度泛函理论(DFT)的第一性原理方法对CaMn_7O_(12)的晶体结构进行了计算和表征,对螺旋桨型磁序的电子结构及相变机制进行了理论分析和研究;在实验方面以TG-DSC为指导,采用固相反应法制备了单相多铁性体CaMn_7O_(12),并检测表征其磁、电学性能。磁学方面验证了CaMn_7O_(12)的2个磁相转变温度(T_(N1)=90 K和T_(N2)=45 K),测得其在10 K温度下存在磁滞回线(Mr=0.02 emu·g^(-1),Hc≈1 000 Oe);电学方面在室温条件下表征其在10 MHz频率时ε_r=280,tanδ=1.69。On theoretical aspect, The R3 crystal structure and the proper-screw magnetic order （the electronic structure and the transformation mechanisms） of CaMnTOl： were calculated by using the first principles calculation based on the density function theory. The purity-phase CaMnTO12 was prepared by solid reaction process according to the TG-DSC analysis in the experiment, which was known as a new single-phase multiferroic material, and its magnetic and electric properties were characterized successfully. Two magnetic phase transition temperature （TN1=90 K and TN2=45 K） and a hysteresis loop at 10 K （Mr=0.02 emu· g^-1 and Hc≈ 1 000 Oe） are measured by the magnetism performance testing. The electrical performance testing indicates that CaMn7Ox2 has the dielectric constant ε=280 and the dielectric loss tanδ=1.69 at room temperature （at 10 MHz）.

关 键 词：CaMn7O12 第一性原理计算 固相反应法 电磁性能 

分 类 号：O641[理学—物理化学] O482[理学—化学]