Fe中刃型位错及其掺杂体系的电子结构

THE ELECTRONIC STRUCTURE AND DOPING EFFECT OF EDGE DISLOCATION IN IORN

用 ＤＭｏｌ团簇方法研究了 ｂｃｃＦｅ［１００］（０１０）刃型位错及其掺杂（碳，氮，磷）体系的电子结构，给出了 Ｆｅ中刃型位错及其掺杂体系的能量参数（结合能、格位能及杂质形成能）和掺氮体系的差分电荷密度．结果表明，杂质与位错芯区近邻基体原子间存在电荷关联区，它反映了位错芯区轻杂质及其近邻基体原子间存在相互作用．Ｆｅ中刃型位错芯区能量计算表明：位错芯区具有捕获轻杂质（碳，氮，磷）的作用，反映了 Ｃｏｔｔｒｅｌｌ气团的量子力学效应．

The DMol molecular-cluster method, based on local density functional approximation, is employed to study the electronic structure and doping effect (carbon, nitrogen, phosphorus) of bccFe[100](010) edge dislocation. The energetic parameters (binding energy, total energy, energy onsite and impurity formation energy), charge-density difference of nitrogen in iron edge dislocation are presented. The results verify there exits a charge correlation region showing the interaction between the impurity and neighbor matrix atoms located in the region of dislocation core. The calculation of energy demonstrates the trapping effect of dislocation core for light impurity, such as carbon, nitrogen and phosphorus, which implies the nature of quantum mechanics of Cottrell atmosphere.