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Information × Registration Number 0222U002359, 0119U002205 , R & D reports Title Electronic and excitonic states in the novel ionic perovskite semiconductors of organic-inorganic type popup.stage_title Head Malyi Taras S, Registration Date 11-02-2022 Organization Ivan Franko National University of Lviv popup.description2 The synthesis of CsPbX3 nanoparticles (X = Cl, Br, I) by "hot injection" method at temperatures of 150-200°C using various organic solvents was improved, which allowed to obtain nanoparticles characterized by a controlled size and narrow size distribution. An effective method for obtaining embedded perovskite nanocrystals in polymer films up to 3 mm thick and a method for obtaining incapsulated perovskite nanocrystals in various porous polymer structures have been developed. Luminescent-kinetic studies in the temperature range of 10-300 K for perovskite nanoparticles with different sizes and composites based on them, as well as thin films using stationary and pulsed optical, synchrotron and X-ray excitation with the duration of excitation pulses of the order of picoseconds. Peculiarities of quantum-size effect and exciton coherence effect are established. An exciton luminescence model in perovskites based on the Rashba effect is proposed, which explains the uncharacteristic features of the luminescence temperature behavior in crystals and nanoparticles and the influence of spatial quantization on the exchange interaction. The features of excitons are taken into account in the proposed model, in which the electron and the hole are formed by mixing the exciton states of many ions. Theoretical calculations of band energy schemes of perovskites within the framework of the generally accepted model of Vanier-Mott excitons using quantum-mechanical approaches are carried out. The values of the exchange interaction based on the wave functions obtained from the first-principle band structure calculations of the crystals are calculated. Product Description popup.authors Dendebera Mykola P Zhyshkovych Andriy V Karnaushenko Vladyslav O Kashuba Andrii І. Liudkevych Uliana I Prunitsa Vitalii V Rudko Mykola S. Salamakha Leonid P Stahura Volodymyr B Stechynska Emiliya T. Chylii Maksym O Shpotyuk Yaroslav O. popup.nrat_date 2022-03-09 Close