Key issues in the targeted synthesis of inorganic substances

Abstract

Chemistry is a science concerned with conversion of substances. From the chemical point of view, a substance is an assemblage of interacting particles, which is characterized by four properties: composition, structure, type of chemical bonding, and particle size. A conversion of a substance is a change in one or several of its properties. Targeted synthesis is a way of controlling a conversion of a substance. This paper considers thermodynamic and kinetic issues in targeted synthesis that are associated with control over the composition, structure, characteristic features of chemical bonding, and particle size and, hence, with the identification of conditions for the preparation of a substance with tailored properties. The concept of pure substance is dis cussed, which is an important issue for materials research and inorganic chemistry. It is pointed out that the composition of compounds should be characterized not only by their stoichiometry and impurity concentra tion but also by the related concentrations of native defects and impurities. In connection with this, a defect classification is presented and defect formation processes and techniques for controlling the defect composi tion are analyzed. Statistical criteria for assessing the compositional homogeneity of a pure substance are con sidered.