Propriedades estruturais, eletrônicas e magnéticas dos óxidos La2−xCaxCoIrO6
I tiakina i:
| Kaituhi matua: | |
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| Rā whakaputa: | 2015 |
| Hōputu: | Master thesis |
| Reo: | por |
| Puna: | Repositório Institucional da UFG |
| Download full: | http://repositorio.bc.ufg.br/tede/handle/tede/4574 |
Whakarāpopototanga: | In this work we describe the synthesis of the novel series La2−xCaxCoIrO6 and its structural, electronic and magnetic characterization. The main objective of this project is to investigate the magnetic evolution of the system when modified due to the chemical substitution of Ca at La site, which can induce changes in the magnetic interactions. The policristaline samples were synthesized by Solid State Reaction process, and studied combining global characterization techniques as powder x-ray diffraction, temperature dependence of magnetic susceptibility and magnetization as a function of applied magnetic field. All compounds crystallize in monoclinic structure, with space group P21/n. Magnetic susceptibility results indicate that the superexchange antiferromagnetic interaction between Co2+ and Ir4+ in La2CoIrO6 lead to ferrimagnetic behavior due to the different magnetic moment of the transition metal ions. For the Ca2+ doped at La3+ site compounds, a magnetic evolution is observed with doping, induced by Co and Ir valence changes. As expected, this system presents a strong correlation between its structural, electronic and magnetic properties, in a way that combining the different results of each compound we can explain its behavior and understand the big picture of this system. |