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Information × Registration Number 0221U101136, 0120U103739 , R & D reports Title Multicolored organic light-emitting diodes (OLEDs) based on ambipolar compounds that exhibit thermally activated delayed fluorescence and aggregate-induced radiation (META). popup.stage_title Head Yashchuk Valerii M., Доктор фізико-математичних наук Registration Date 15-01-2021 Organization Taras Shevchenko National University of Kyiv popup.description2 The object of research - electronic processes that occur in organic systems as a result of their excitation due to various factors. The aim of the project is to study the luminescent properties of heterostructured organic materials, including the ability to retain fluorescence (TADF), which allows the use of these materials in organic LEDs. Research methods - optical spectroscopy. Experimental methods for studying the absorption spectra, instantaneous and delayed fluorescence, as well as phosphorescence of investigated organic compounds have been developed. The design of molecular emitters with high quantum yield is carried out. According to the results of design and experimental research, the most effective emitters were selected. Processing and preliminary analysis of the results of spectral studies is carried out. It is shown that for solutions of fluorescent compounds LS26, LS26, LS29, I, II, III, IV the absorption and fluorescence spectra at a temperature of 300 K are mainly monomolecular in nature. The luminescence spectra of these substances in the solid state and in solutions at low temperatures are more complex, which is due to internal transformations in excited molecules, the transfer of electron excitation energy in these systems and the formation of aggregates. Preliminary results indicate that at 300 K there is generally no delayed radiation for compounds LS26, LS26, LS29. At the same time at 77-200 K this radiation is present. The processes of aggregation formation in the studied systems are studied. The absorption and fluorescence spectra of compounds I, II, III, IV at 300 K in the solid state (films created by thermal application in vacuum) indicate the formation of aggregates. Product Description popup.authors Hrynʹ Dmytro V. Losytsʹkyy Mykhaylo Yu. Navozenko Oleksandr M. popup.nrat_date 2021-01-15 Close