The intrinsic properties of a solid, i. e., the properties that result from its specific structure, can be largely modified by crystallographic and chem- ical defects. The formation of these defects is governed by the heat and mass transfer conditions which prevail on and near a crystal-nutrient in- terface during crystallization. Hence, both the growth of highly perfect crystals and the preparation of samples having predetermined defect-induced (extrinsic)...