Defects Near Ionic Crystal Surfaces
Changes in the defect distribution on approaching the free surface of a crystal may be of considerable importance in understanding many surface phenomena. A detailed knowledge of the atomic arrangement in the surface region is not readily obtainable from experiment, but it is of interest to investigate from a theoretical viewpoint the influence that point defects are likely to have on certain surface properties. We will discuss here and review some attempts to predict the distribution of point defects in the vicinity of ionic crystal surfaces and examine how some of these ideas may be applied in the treatment of morphological changes governed by capillarity. For simplicity, we will Hmit the discussion to ionic crystals having the NaCl structure and in which only defects of the Schottky type occur.
KeywordsCreep Rate Frictional Force Anion Vacancy Vacancy Formation Energy Displacement Polarizability
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