Computer Simulation of Point and Line Defects in Iron and Copper

Abstract

Computational techniques are playing an ever-increasing role in the calculations of both the electronic and structural properties of defects in solids. Although all such calculations should ideally be done within a fundamental quantum mechanical framework, the complex nature of the atomic configuration associated with most defects has precluded this and many defect properties cannot yet be discussed with a fundamentally satisfactory model. The situation is particularly acute when a principle objective of the calculation is the determination of the atomic configuration in the neighborhood of the defect or of a property that depends directly on the configuration. To deal with such problems a procedure which we shall refer to as computer simulation has been devised and applied to various defect solids. The present paper will outline the essential features of such procedures and give some justification for the approach. In fact, we shall see that the main justification follows by looking at some specific examples where computer simulation has provided explanations of phenomena that could not otherwise be explained.