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Information × Registration Number 0217U002816, 0117U003122 , R & D reports Title Development of methods for change of 3d-ions electronic and spin states and search control methods for bistable properties of multifunction materials popup.stage_title Head Levchenko Heorhiy Heorhiyovych, Registration Date 11-12-2017 Organization Donetsk Institute of Physics @ Engineering named after O.O.Galkin NAS of Ukraine popup.description2 Report about the scientific research work: 72 p., 33 Figs., 4 Tables,108 ref. The research work is devoted to the actual problem of the modern physics - development of methods for electron and spin states changing in molecular and molecular-like materials and searching possibilities for production a new necessary for using properties of these multifunctional compounds. This work is the continuation of the research work held in 2016 with same name. So it was made additional investigations of spin-crossover in compounds studied in the first part of the project and in addition compounds with aim to study spin-crossover influence on their magnetic properties. It was researched possibilities for changing of electron and spin states in molecular-like compounds containing 3d-ions Fe, Mg, Co. It was studied properties of quantum baromagnetic effect connected with the changing of spin state of magnetic ions. This effect changes magnetic properties of materials. Among molecular-like compounds with the perovskite structure it was changed compounds containing bismuth with ferroelectric properties. The general for these materials is possibility to control their useful properties by way of changing electron and spin states. In was determinate that using of pressure offers to shift a spin transition in Hoffman-like polymers to room temperature and, as result, we have a phase transition with large hysteresis at room temperature which may be used in practices. It was calculated interaction parameters and enthalpy changing for some Hoffman-like compounds and showed incompatibility of phase diagrams temperature-high spin part and pressure-low spin part. A new control method for spin state of spincrossover compounds basing on piezoelectric effect was proposed. It changes pressure on the sample by electric voltage. Design of hybrid high pressure cell was proposed. It changes pressure by electric voltage to 0.4 kbar and controls transition a good plan. Transition party is detected by optical method. A chemical method (replace method) for electron and spin state control in perovskites was studied. This method is used broadly for obtaining useful properties in magnetoresistive materials. We determined a feedforward of defect formation at replacing in A underlattice and caking temperature changes with magnetoresistive materials properties and obtained real chemical formula for studying materials. PHASE TRANSITIONS, ELECTRON STATES, SPIN, PIEZOELECTRIC EFFECT MAGNETORESISTIVE MATERIALS Product Description popup.authors Бочкова Галина Юріївна Пащенко Олексій Валентинович Прокопенко Василь Кирилович Филь Геннадій Павлович popup.nrat_date 2020-04-02 Close