Krykunova V. Pyrene aggregation penetrabilities

Object: crystalline pyrene, solid solutions of pyrene in poly(methyl methacrylate), (vinylpyrene-methyl methacrylate) copolymers, liquid solutions of pyrene in organic solvents and in water. Aim: to establish the structure of potential surfaces of pyrene dimer in the ground and excited states under chromophore aggregation in crystalline phase, liquid solutions and polymeric media by spectral methods. The methods of investigations are spectrometry, spectrofluorimetry, synchronous scanning of fluorescence. Photophysical processes scheme that describes excitation of excimeric fluorescence in liquid solutions of molecules is modified and its analysis is conducted. The relation of energy states, in which pyrene dimers are stable, with vibronic characteristics of electronic absorption spectra of monomer is shown. The dependence of solvatochromic shift of pyrene excimeric fluorescence is established. The method of determining of the monomer-dimer ratio by spectral methods and effectiveness of radiationless e nergy transfer from monomer to dimer is proposed. The results of work have to be taken into account when using methods based on the study of excimeric fluorescence for a determination of the structure and morphology of a media, for investigations in molecular kinetics. The data achieved in the work are importance for purpose of founding of all sources of optical losses in chromophore containing organic materials used as optical fibbers and scintillators. The application spheres are scientific studies and a practice of the spectral analysis.