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Information × Registration Number 0203U006049, 0100U001360 , R & D reports Title Mechanisms of hyperfine fields formation and kinetics of charge carriers in magnetic semiconductors. popup.stage_title Head Berzhansky, Vladimir, Registration Date 14-02-2003 Organization National Taurida V. Vernadsky University popup.description2 Using the LKAO method we have obtained analytic expressions for covalent contribution in hyperfine magnetic interactions in chromium chalcogenide spinels. Using ions of Ga3+, In3+, Sn4+ as diamagnetic probe, we show that charge number of valent shells of diamagnetic cations is proportional to electron transfer parameter in chromium-ligand-cation connection. Theory of multi-quantum effects in NMR spectroscopy with three-impulse excitation and arbitrary numbers of nuclear spins was developed. We have studied multi-quantum effects on 53Cr, 55Mn, 65,63Cu nucleus and show theory and experiment accordance. For the first time multi-quantum signals from tetrahedrically coordinated Cu ions and additional Cr signals near defect positions in chalcogenide chromium spinels with Sb doping has been discovered. The dependence of NMR parameters on the degree of Sb doping has been determined.Magnetic properties, conductivity and magnetic resistance in crystals of Mn ferrites with various stechiometry has been studied.We show that these compounds is wide-zone magnetic conductors at high temperatures and their anomalous temperature dependencies of these parameters mainly related with magnetic contribution in activation energy of carriers.Estimation of s-d-interchange interaction integral of collectivized and localized electrons was accomplished. Product Description popup.authors popup.nrat_date 2020-04-02 Close