元素(M=Fe,Mn)掺杂立方相BaTiO_(3)性能的第一性原理研究  

First principle study on the properties of cubic BaTiO_(3)doped with elements(M=Fe,Mn)

作　　者：徐良玉 龙敏 黄福祥[1] 邓鸿元 陈剑 XU Liangyu;LONG Min;HUANG Fuxiang;DENG Hongyuan;CHEN Jian(College of Materials Science and Engineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学材料科学与工程学院,重庆400054

出　　处：《重庆理工大学学报（自然科学）》2023年第5期135-141,共7页Journal of Chongqing University of Technology：Natural Science

基　　金：重庆理工大学研究生创新基金项目(clgycx2020307)。

摘　　要：根据密度泛函理论框架下的第一性原理方法,计算了元素(M=Fe,Mn)掺杂立方相BaTiO_(3)(BaFe_(x)Ti_(1-x)O_(3)、BaMn_(x)Ti_(1-x)O_(3),x为0、1/8、1/4、3/8、1/2)的晶体结构、电子结构、磁矩、介电函数。计算结果表明:当x为1/8时,BaTiO_(3)的晶体结构仍然保持为立方相;当x大于1/8时,BaTiO_(3)的晶体结构转变为四方铁电相。掺杂元素Fe、Mn使BaTiO_(3)获得了较大的磁性,总磁矩主要来源于Fe、Mn离子局域磁矩的贡献。随着元素掺杂量的增大,BaTiO_(3)的磁性增强。对比掺杂前后静态介电常数发现,掺杂元素Fe、Mn使BaTiO_(3)静态介电常数改变较大,且远大于掺杂前,因此,Fe与Mn更容易使BaTiO_(3)获得高介电常数。The crystal structure,electronic structure,magnetic moment and dielectric function of an element(M=Fe,Mn)doped with cubic BaTiO_(3)(in which the chemical formulas are BaFe_(x)Ti_(1-x)O_(3)or BaMn_(x)Ti_(1-x)O_(3),and x is 0,1/8,1/4,3/8 or 1/2)are calculated by using the first principle method under the framework of the density functional theory.The results show that,when x is 1/8,the crystal structure of BaTiO_(3)remains cubic phase,while,when x is greater than 1/8,the crystal structure of BaTiO_(3)changes into tetragonal ferroelectric phase.The addition of Fe or Mn makes BaTiO_(3)obtain great magnetism,and the total magnetic moment mainly comes from the contribution of the local magnetic moment of Fe or Mn ions.With the increase of element doping,the magnetism of BaTiO_(3)increases.At the same time,by comparing the static dielectric constant before and after doping,it is found that the doping of element Fe or Mn makes the static dielectric constant of BaTiO_(3)change greatly,which is much larger than that of the undoped BaTiO_(3).Therefore,Fe and Mn are easier to obtain the high dielectric constant.

关 键 词：BaTiO_(3) 掺杂 第一性原理 介电函数 磁性 

分 类 号：TB34[一般工业技术—材料科学与工程]