含平面界面晶体的格点格林函数
Lattice Green's function for crystals containing a planar interface
摘要：
灵活的边界条件方法耦合一个孤立的缺陷，通过体晶格格林函数的谐波响应介质，在界面的情况下，界面晶格格林函数。我们提出了一种方法来计算任意原子相互作用的平面界面的晶格格林函数，适合于线缺陷/界面相互作用的研究。界面耦合到两个不同的半无限体区域，和格林函数的界面界面，体界面和体体相互作用分别计算。弹性双晶格林函数和体晶格格林函数给出了体区域之间的相互作用。我们利用部分傅里叶变换来处理平面内的周期性。部分傅立叶空间中的力常数矩阵的直接求逆提供了界面项。一般的方法不对原子相互作用或晶体取向作任何假设。采用柔性边界条件模拟了钛中螺旋位错与$(10\bar{1}2)$孪晶界的相互作用，并与传统的固定边界条件的结果进行了比较。灵活的边界条件给出了正确的核心结构，需要通过能量最小化来松弛的原子显著减少。这突出了灵活的边界条件方法的适用性，通过\textit{ab initio}方法模拟缺陷/界面相互作用。
英文摘要：
Flexible boundary condition methods couple an isolated defect to a harmonically responding medium through the bulk lattice Green's function; in the case of an interface, interfacial lattice Green's functions. We present a method to compute the lattice Green's function for a planar interface with arbitrary atomic interactions suited for the study of line defect/interface interactions. The interface is coupled to two different semi-infinite bulk regions, and the Green's function for interface-interface, bulk-interface and bulk-bulk interactions are computed individually. The elastic bicrystal Green's function and the bulk lattice Green's function give the interaction between bulk regions. We make use of partial Fourier transforms to treat in-plane periodicity. Direct inversion of the force constant matrix in the partial Fourier space provides the interface terms. The general method makes no assumptions about the atomic interactions or crystal orientations. We simulate a screw dislocation interacting with a $(10\bar{1}2)$ twin boundary in Ti using flexible boundary conditions and compare with traditional fixed boundary conditions results. Flexible boundary conditions give the correct core structure with significantly less atoms required to relax by energy minimization. This highlights the applicability of flexible boundary conditions methods to modeling defect/interface interactions by \textit{ab initio} methods.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
