锰酸镧晶体本征点缺陷的模拟研究  

Simulation of the Intrinsic Defects in LaMnO_3 Crystal

作　　者：赵朝珍[1] 刘廷禹[1] 李妍[1] 

机构地区：[1]上海理工大学理学院,上海200093

出　　处：《人工晶体学报》2013年第6期1159-1165,共7页Journal of Synthetic Crystals

基　　金：上海理工大学国家级项目和人文基地培养计划(12XGM02)

摘　　要：本文利用晶格动力学GULP软件模拟计算了理想立方结构LaMnO3晶体的本征缺陷以及氧空位迁移能。利用离子之间的相互作用势计算得到的结果与实验结果吻合得很好。同时计算了理想立方结构LaMnO3的体弹模量,杨氏模量,泊松率,弹性常数,静介电常数,高频介电常数。通过对本征缺陷形成能的分析得到以下结论:LaMnO3晶体中主要存在的各类缺陷为氧空位、填隙锰、氧的夫伦克尔缺陷和锰替位镧反位缺陷;氧空位的迁移能为0.362 eV,它表明氧在晶体中容易迁移。In this paper,the intrinsic defects and oxygen vacancy migration energy of perfect cubic structure of LaMnO3 crystal have been studied by General Utility Lattice Program(GULP).The calculated results on the basis of interaction potential between the ion are in good agreement with the experimental results.The bulk modulus,Young 's modulus,Poisson rate,elastic constants,static dielectric constant,high-frequency dielectric constant for the perfect cubic structure of LaMnO3 have been obtained.By analyzing of the intrinsic defect formation energies,the following conclusions are obtained: the oxygen vacancy is easily formed and the oxygen Frenkel disorders are the main intrinsic defects in LaMnO3 crystal;The activation energy of oxygen vacancy migration is 0.362 eV in LaMnO3 crystal,It is indicated that the oxygen is moveable in the crystal.

关 键 词：LaMnO3晶体 钙钛矿 本征缺陷 模拟计算 

分 类 号：O77[理学—晶体学]