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We have investigated correlation between magnetization and electronic structure in Zn0.98Mn0.02O nano-rods. Rietveld analysis of XRD patterns confirms that Mn ions incorporate at the Zn2+ sites. SQUID measurements confirm that Mn doping induces room temperature ferromagnetism (RTFM) in nano-rods and the induced magnetization is an order of magnitude higher than that in the bulk Zn0.98Mn0.02O. The XPS results show that Mn ions are in mixed valent state. Our findings show that bivalence of Mn ions and the oxygen vacancies are responsible for the observed RTFM. [ABSTRACT FROM AUTHOR]

We demonstrate that room temperature ferromagnetism (RTFM) can be induced in pristine In2O3 bulk powder through hydrogenation. The oxygen vacancies (Vo) accompanied by defect complexes In2+-Vo are produced in hydrogenated In2O3. However, the ferromagnetic ordering disappears upon removing these Vo's and defect complex upon re-heating the hydrogenated sample in air. The hydrogenation induced In3d-O2p hybridization, the defect complexes In2+-Vo and the Vo's compositely contribute to observed ferromagnetic ordering. [ABSTRACT FROM AUTHOR]

Nanocystalline Cu0.2Ni0.8Fe2O4 of average particle size 3 nm was synthesized through chemical coprecipitation method followed by annealing at various temperatures. The formation of cubic spinel structure in single phase and the crystallite growth was confirmed using XRD. The dielectric behavior as a function of frequency in the range 75 kHz to 10 MHz was studied at room temperature. Both dielectric constant ([variant_greek_epsilon]′) and the loss factor (tanδ) decreases with frequency for all samples. This decrease in the values could be explained on the basis of available ferrous, i.e. Fe2+, ions at octahedral sites such that beyond a certain frequency of applied electric field the electronic exchange between the ferrous and ferric ions i.e. Fe2+↔Fe3+ cannot follow the applied alternating electric field. [ABSTRACT FROM AUTHOR]

We demonstrate that room temperature ferromagnetism (RTFM) can be induced in pristine In2O3 bulk powder through hydrogenation. The oxygen vacancies (Vo) accompanied by defect complexes In2+-Vo are produced in hydrogenated In2O3. However, the ferromagnetic ordering disappears upon removing these Vo's and defect complex upon re-heating the hydrogenated sample in air. The hydrogenation induced In3d-O2p hybridization, the defect complexes In2+-Vo and the Vo's compositely contribute to observed ferromagnetic ordering. [ABSTRACT FROM AUTHOR]