硅酸镥晶体本征缺陷和力学性质的研究  

Study on the Intrinsic Defect and Mechanical Properties of Lu_2SiO_5 Crystal

作　　者：夏贯芳 刘廷禹[1] 张涵[1] 高肖丽 

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12期2691-2695,2700,共6页Journal of Synthetic Crystals

摘　　要：采用GULP软件研究了硅酸镥晶体的本征缺陷、力学性质和氧空位的迁移。采用已有的势参数计算得到的结构参数与实验结果吻合的很好。与其他的氧空位相比,VO5的缺陷形成能最低,因此氧空位主要以VO5的形式存在。O的弗伦克尔缺陷具有最低的缺陷形成能,所以氧的弗伦克尔缺陷可能是晶体中存在的最主要的本征缺陷。本文还计算了晶体的弹性常数、体积模量、压缩系数、杨氏模量、泊松比率等力学性质。通过计算相邻氧格位之间氧空位的迁移能,发现O1,O2,O3和O4之间的迁移比较容易。The intrinsic defects, mechanical properties and oxygen vacancy migration of Lu2SiO5 crystal were studied by computer simulation. Using the GULP software, the potential ＂parameters were calculated and were proved to be well agree with the experiment results. The oxygen vacancy Vo5 has the lowest formation energies compared with the other four types of oxygen vacancies, so Vo5 was the dominant oxygen vacancy. Freckle defects of oxygen would be the predominant intrinsic defect in the crystal because it has the lowest defect formation energy. The elastic constants, bulk modulus, compressibility, Young Modulus, and Poisson ratios were also given in the calculations. The activation energies of the oxygen vacancy were given by calculating the defect energies along different migration paths between adjacent oxygen sites, and the oxygen vacancy migration among O1 , O2, O3 and O4 sites is comparatively easy.

关 键 词：硅酸镥晶体 力学性质 本征缺陷 氧空位 

分 类 号：O771[理学—晶体学]