面心立方铜中小空位团簇结构及稳定性的讨论

本文应用改进分析型嵌入原子法讨论了面心立方铜中密排面上四个三空位和二十个四空位的可能构形及稳定性。表明:一个三空位和六个四空位松弛后构形发生塌陷;从能量最小化观点得出,三空位以四个位于顶点空位和一个位于中心的间隙原子构成的正四面体的构形存在,四空位以六个住于顶点的空位包围着两个间隙原子构成的八面体的构形存在;形成能随空位数目的增加而增加,但稳定构形空位中平均一个空位的形成能随空位数目的增加而减小。

The Discussion of Structure and Stability of Small Vacancy Clusters inFace-centred-eubic Metal of Copper

In face-centred-cubic metal of copper,the possible structures and stability are discussed of 4 distinct types of close-packed trivacancy and 20 types of tetravacancy with modified analytical embedded atom method.The results are shown that one of the trivacancies and six of the tetravacancies are found to relax to collapsed forms;from energy minimization,the trivacancy exists stably with the configuration of a regular tetrahedron of four vacancies with an interstitial at its centre,and the tetravacancy exists stably with the configuration of six vacancies are at the corners of two tetrahedral with two di-interstitial at its centre;formation energy increase with the increasing of the number of vacancy, on the contrary,for the formation energy of an average one vacancy in stable configuration.