Marx, V. (PhD)Chanyalew, Sisay2018-06-222023-11-092018-06-222023-11-092000-06http://etd.aau.edu.et/handle/12345678/2930Schottky formation energy of some sixteen alkali halides with NaCl structure and cluster size of 1728 ions was calculated using numerical summation of Coulomb, repulsive and Van der Waals interaction. The energy difference between a cluster with a point defect and the corresponding perfect cluster represents the formation energy of defects. It could be shown that the structure of vacancies in the bulk and the surface position of the removed ion have a strong influence on the formation energy Schottky defects.enFormation energy halides with NaClThesis