TO QUESTION ABOUT NATURE AND MODELLING THE PROCESSES OF NUCLEATION AND CRYSTALLIZATION

Abstract

The main problems of nature and modelling the nucleation and crystallization are discussed. Two aspects of this problem: thermodynamical and electrodynamical, are discussed. Nucleation processes are classed as heterogeneous o r homogeneous. Main thermodynamic theories and models of thermodynamic nucleation and crystallization, including Stranski-Krastanow model, are analyzed. It is shown, that these theories are explained the classic crystallization processes and methods, including Kiropoulos method, Chochralsky method, Bridgman-Stockbarger method, methods of zonal crystallization, growing with solution mixture. Vitaliy Stafeev electrostatic phason model, cascade theories of excitation of corresponding chemical bonds (coordination numbers) are represented electromagnetic models. Vitaliy Stafeev model allow to estimate minimal sizes of new phases – phasons and may be used for continuous and pulse regimes of nucleation and crystallizations. Cascade theories allow to explain the laser-induced pulses phase transformations. In this case we can have new phases with an increase in the degree of order (irradiation of the unstable or metastable structures), as well as with a decrease in the degree of order (irradiation of the stable structures). Examples of the use of these theories to describe phase changes during laser irradiation of silicon, germanium, indium antimonide, and indium arsenide are given. These theories may be used for all possible matter: from neorganic to biological. The problem of saturation is on of central problem of these theories. This problem has two ways of resolution. For thermodynamical theories and models it is saturation of solutions and dynamic of change this saturation. For electromagnetic theories and models it is the saturation of excitation and intencity of this excitation. The perspective of development and application these methods are discussed.