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Information × Registration Number 0224U031680, 0122U001961 , R & D reports Title Chemical design of multifunctional coordination compounds and bistable supramolecular materials popup.stage_title Head Frytskyi Ihor O., Доктор хімічних наук Registration Date 05-06-2024 Organization Taras Shevchenko National University of Kyiv popup.description2 The research of bistable materials is an active area of world-class research. One of the reasons for the increased interest in these objects is the rapid achievement of the smallest elemental limit of silicon microchips, which is limited by the length of quantum tunneling (1.5-2 nm). In the case of spin-crossover compounds, a single molecule acts as an elementary carrier of bistability, which in the future allows creating memory devices with ultra-dense information storage capacity, unattainable for modern technologies. As a result of this work, the bistability of a single spin-crossover molecule in the adsorbed state was demonstrated, which will be used to construct a memory device with ultra-dense information storage capacity. The switching of spin states due to electron injection or photon absorption will be useful for creating spintronic or photonic molecular devices. Polymorphism in spin-crossover compounds makes it possible to obtain additional forms of switchable materials with various properties. In the course of this project, three polymorphic modifications of the new spin-crossover complex were obtained. They demonstrate different characteristics of the spin state change: The α-form exhibits a hysteretic one-step transition centered at 134 K, the β-form undergoes a hysteretic two-step spin transition with plateau (T1/2 = 153 and 144 K), and the γ-form remains high spin in the entire temperature range studied. The kinetic origin of the hysteresis loop was demonstrated in magnetic measurements that depended on the rate of temperature change. The spin transition in the α-form is accompanied by a decrease in symmetry from a single Fe(II) center in the high-spin state to two different Fe(II) centers in the low-spin (LS) state. In the β-form, the X-ray crystallographic analysis revealed a change in symmetry associated with a step transition, with the presence of both spin forms in the temperature range of plateau. Product Description popup.authors Vynohradov Oleksandr S. Kucheriv Olesia I. Plutenko Maksym О. Serediuk Maksym L. Tsapiuk Halyna H. popup.nrat_date 2024-06-05 Close