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Information × Registration Number 0220U104484, 0119U100309 , R & D reports Title Mechanisms of complex formation and electronic excitations in compounds of conjugated systems with nanostructures. popup.stage_title Head Pavlenko Olena L., Кандидат фізико-математичних наук Registration Date 19-12-2020 Organization Taras Shevchenko National University of Kyiv popup.description2 Object of research: films of merocyanine dyes and their bases, squarain dyes with metal nanoparticles, C60 fullerenes, their complexation. Purpose: to establish the mechanisms of interaction of dyes with nanostructures, characterization of their complexation. Research methods: optical absorption spectroscopy, photoluminescence, X-ray diffraction analysis, atomic force microscopy, quantum chemical methods of density functional theory, semi-empirical methods AM1, PM6, ZINDO. The absorption spectra of molecules of dye bases and merocyanines, as well as squarains in films, including in the interaction with metal nanoparticles and C60, have been studied. Quantum chemical calculations revealed the nature of absorption for all studied types of dyes, it was shown that their condensation interacts, namely the formation of aggregates depending on the charge distribution in the conjugate chain, symmetry of the molecule, functional groups, and deposition modes. It was found that the absorption spectra of monomer molecules differ from those characteristic of condensing films of the studied molecules, which is confirmed by vacuum spraying of dyes on the substrates. The spectral properties of dye films interacting with carbon nanoparticles are characterized by shifts in the absorption peaks relative to pure films; in the presence of metal nanoparticles, the transformation of spectra is more significant due to the interaction of molecules with nanoparticles. The calculations show that the changes in the spectra are due to a change in the geometry of the dye molecules in complexes with nanoparticles, which is a consequence of the transfer of charges from the dyes to the nanoparticles.  Product Description popup.authors Busko Tatiana O. Lesiuk Andrii I. Nikolaienko Tymofii Yu. popup.nrat_date 2020-12-19 Close