摘要
利用原子级计算机模拟对四方SrTiO3中畴壁能进行了研究.在经典Born模型基础上用来描述离子晶体的原子级模拟,其能量表达式由长程库仑势和短程排斥势构成.后者为一含参数表达式,式中参数可由晶体的晶格常数、晶体结构和弹性常数等实验数据拟合得出.四方SrTiO3由高温立方SrTiO3相变而来,应存在反相畴界、孪晶界和平移孪晶界等3种畴界.本文用原子级模拟的技术对这3种畴界能进行了计算.结果表明畴界能尤其是反相畴界能非常小.
In this work the domain boundary energies in tetragonal SrTiO 3 are studied by atomistic computer simulation technique. The atomistic simulation is based on the classical Born model in which the lattice energy is the sum of firstly long range Coulombic interactions and secondly short range repulsive interactions. The second form is described by adjustable parameters which can be fitted by lattice parameters, crystal structure and elastic constants. Tetragonal SrTiO 3 is transformed from high temperature cubic SrTiO 3, hence there should be three orientation domains V x, V y and V z whose C directions are parallel to the cubic , and directions respectively and anti phase domains in each orientation domain. This work studied the energies of anti phase domain, twin and translation twin boundaries. The results reveal very low domain boundary energies for tetragonal SrTiO 3, especially for the anti phase domain boundary.
出处
《武汉大学学报(自然科学版)》
CSCD
1998年第3期343-346,共4页
Journal of Wuhan University(Natural Science Edition)
关键词
畴界能
原子级模拟
钛酸锶晶体
atomistic simulation, tetragonal SrTiO 3, domain boundary energy