ANALYTICAL AND SYNTHETIC APPROACH TO BUILDING A MODEL OF A SYSTEM OF EMITTING CENTERS OF SINGLE CRYSTAL COMPOUNDS WITH WIDE LUMINESCENCE SPECTRA

Abstract

To date, there is no definite technique for studying systems of emitting luminescence centers, although there are methods that make it possible to single out individual bands for solving the problems of classifying emitting centers by their position in the crystal lattice and revealing their behavior when changing the conditions of luminescence excitation. Due to certain circumstances, far from all of them are convenient in practical application and make it possible to obtain adequate models of individual luminescence bands under various experimental conditions. The technique for analyzing a system of emitting luminescence centers by decomposition into individual components and constructing their adequate quantitative models is proposed in this work. The joint use of both analytical and synthetic approaches is considered. The first one is aimed at clarifying what the system under consideration consists of, and the second allows one to find answers to questions related to the interaction of the system under consideration with the environment. Both approaches complement each other. The mathematical description of the developed models is presented. It describes the changes in the number of luminescence centers with a certain type of local environment relative to the total number of all luminescence centers when the excitation conditions change, which, in turn, makes it possible to obtain information on changes in the structure of the materials under study. A normal distribution was used to isolate individual bands associated with the emission of certain types of luminescence centers. Considering that the presence of various phonon or other effects caused by the influence of the crystal lattice does not allow an accurate description of individual bands using a normal distribution, it is advisable to use both the energy scale of the emitted photons and the wavelength scale as coordinates along the abscissa axis to obtain quantitative models of luminescence centers with a change in the excitation conditions.