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Information × Registration Number 0224U033265, (0123U103143) , R & D reports Title Impact of an additional photoactive group in azo-compounds on the nature of nonlinear optical responses of polymer composites popup.stage_title Дослідження пружного розсіяння світла (532 нм) для композиційних полімерних матеріалів типу «гість-хазяїн» на основі синтезованих фотохромів. Дослідження прояву самовпливу імпульсного лазерного випромінювання в полімерних композитах, що містять сполук з двома фотоактивними містками та різними електрон-донорними замісниками при збудженні імпульснім лазерним випромінюванням на довжині хвилі 532 нм та 1064 нм. Head Ovdenko Valeriia M., Кандидат хімічних наук Registration Date 23-12-2024 Organization Institute of Physics of National Academy of Sciences of Ukraine popup.description1 The purpose of this project is an experimental study of nonlinear optical (NLO) properties, namely the effects of the self-action under pulsed/continuous laser radiation and the phenomena of the optical harmonics generation as a manifestation of degenerate and non-degenerate cubic optical nonlinearity, respectively, in solutions/films of photoactive polymers and hybrid materials with covalently or physically introduced azo-/azomethine chromophores, which are promising for use in optoelectronics, nonlinear optics, and means of recording, storing, and converting information. popup.description2 The object of the study - azo compounds/ azomethines based on benzene/pyridine fragments, azonaphthols with different number of azo bridges (one/two) as materials for polymer composites with high nonlinear optical (NLO) response development. The aim of the project - to determine the effect of the photochromic compounds structure on the NLO response value in polymer films: to study the effect of the heterocyclic nitrogen atom introduction, the replacement of the azo π-bridge with an azomethine one, the transition from mono-azo compounds to azo compounds with two photochromic bridges. Research methods: quantum chemical investigation of the optimal geometry, spectral and nonlinear optical properties using DFT methods, structure studies using NMR and IR spectroscopy, UV-vis spectroscopy, study of the refractive and absorptive NLO response of thin films via the self-action of laser radiation investigating. In the second stage of the project, three azomethines, which are structural analogues of the azo compounds studied in the first stage, as well as two bis azo compounds, were investigated. The study of the self-action effect of continuous under laser radiation (532 nm) showed a significant difference in the response of the unirradiated film compared to the irradiated with a full spectrum mercury UV lamp one. Depending on the azomethine` structure, a tendency to self-focusing (pyridine-containing) or self-defocusing (benzene-containing) was observed under UV irradiation. The difference in the refractive response for unirradiated and irradiated samples could be up to 3.5 %. The study of photo-induced changes under the action of pulsed laser radiation (532 nm) for azo compounds demonstrated a clear effect of photo-bleaching (3-4 %) for compounds with a benzene fragment and a photo-darkening effect (4 %) for pyridine-containing one. All substances showed oscillatory changes in the curves with increasing laser intensity. Product Description popup.authors Ovdenko Valeriia M. popup.nrat_date 2024-12-23 Close