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Information × Registration Number 0225U002968, (0124U001443) , R & D reports Title Bistable compounds for adaptive masking, energy-saving "green" technologies and molecular electronics popup.stage_title Розробка і напрацювання методик синтезу, синтез та ідентифікація сполук. Head Seredyuk Maksym L., Доктор хімічних наук Registration Date 27-04-2025 Organization Taras Shevchenko National University of Kyiv popup.description1 The goal of the project is to select and modify ligand systems based on available libraries of organic synthons, taking into account potential changes in the molecular periphery; synthesis of transition metal compounds based on N,O-polydentate ligands with a given type of supramolecular interactions that will provide controlled spin-crossover, spectral and color characteristics of compounds in combination with high chemical stability and high entropy gain; study of their magnetic and spectral properties; elucidation of the structure-property relationship for metal complexes and development of scientifically sound approaches to create a new generation of bistable functional compounds. popup.description2  The implementation of modern methods of cheminformatics allows us to identify starting materials and realistic scenarios for the synthesis of different types of ligands to create new compounds with useful properties. The capabilities of the approach are demonstrated by the example of creating a compound for barocaloric applications. Barocaloric cooling, that is, lowering the temperature of a material under pressure ac-tion, is an attractive solid-state effect that can potentially compete with volatile gas-based cooling. To observe the barocaloric effect (BCE), it is necessary for materials to have high-entropy, low-hysteretic phase transitions with a large volume change be-tween phases. Here details on a new FeII complex [Fe(L)(NCS)2], L = N1,N3-bis((1-propyl-1H-1,2,3-triazol-4-yl)methylene)-2,2-dimethylpropane-1,3-diamine) pos-sessing spin crossover (SCO) behavior near room temperature with large entropy and volume change are reported, which provides high sensitivity to external pressure. The observed BCE effect, characterized using variable pressure calorimetry, powder X-ray diffraction, UV–vis, IR, and Raman spectroscopy, shows a colossal isothermal entro-py change of >100 J kg−1 K−1 and a reversible adiabatic temperature change of ≈16 K at a pressure of 1 kbar, demonstrating a high refrigerant efficiency compared to other solid-state materials. Product Description popup.authors Kariaka Nataliia S. Malinkin Serhii O. Moroz Yurii S. popup.nrat_date 2025-04-27 Close