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Information × Registration Number 0307U001719, 0106U003131 , R & D reports Title The phase diagram and mechanisms of the formation frustrated electric and magnetic states of the different types popup.stage_title Теплофізичні та магнітні властивості змішаних кристалів Head Anders Olexandr Georgiyovich, Registration Date 19-04-2007 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of the study - the policrystal diluted ferrimagnetic oxides BaFe12-xInxO19 (x Ј 3,5) and In3,6M and monocrystal Cu(phen). The methods of the studies - static magnetic and dilatometric methods, electronic paramagnetic resonance. The investigations of the magnetic temperature dependencies of the inverse ferrimagnetics BaFe12-xInxО19 with x = 3,2 and 3,4 are carried out. The possibility of the resonance methods use for study of the phase states and exchange parameters of the space-unhomogeneous magnetics is simultaneously researched. The syntheses and attestation of the polycrystal samples of the system BaFe12-xInxO19 (x=3,2 and x=3,4) were carried out. The temperature dependencies heat capacity C(T) at T< 20 K were experimentally considered as well as phonon (Cf) and magnetic (Cm) contributions were separated by analytical method. It is established that: 1. Concentration transition between spin glass state (SG) that was found for sample x=3,6 and mixed states exists in concentration range 3,4<x?3,6. These mixed states simultaneously have glass state properties and spontaneous magnetization ?S ? 0; 2. For the first time it was found that these states (with ?S?0) have a dependence Cm(T)~Т3/2 (the law of the spin waves) as well as in the case of x=3,0 (our previous studies) while only linear dependencies C(T)~Т (like for spin glass) were observed earlier. It is established that information of the magnetic resonance spectrum of the small-dispersive powder can be compare with information of the spectrum of the monocrystal for spin S=1/2. The possibility of the determination efficient g-factor and resonance line widths of the individual particle of powder from resonance absorption band of the complex form is demonstrated on example of the EPR spectrum of the powdered sample Cu(phen) contained the Cu2+ ions. Product Description popup.authors popup.nrat_date 2020-04-02 Close