Resumo

SAAVEDRA-GAONA, I. M. et al. Influence of the ionic radius on structural and magnetic response of the system Pr_0.48TR₀.₀₂Ca_0.5Co0_3-δ. Rev. ion [online]. 2018, vol.31, n.1, pp.65-69. ISSN 0120-100X.  https://doi.org/10.18273/revion.v31n1-2018011.

The metal - insulator transition (MIT), of the oxides type perovskite formed by elements of Rare Earths (TR), presents an interesting behavior in the family derived from Pr0.5Ca0.5Co03-δ. In this paper it is studied the influence of ionic radius of the rare earth TR in the crystalline structure and in the synthesis of the new family perovskite type Pr0.48TR0.02Ca0.5Co03-δ (TR=Eu,Sm,Dy),produced by the technique of the solid state reaction. The structural characterization of the system was realized by X-rays diffraction (XRD) and Rietveld analysis, demonstrating that the samples crystallize in a orthorhombic structure with spatial group Pnma (#62), without significant changes in phase structural generated by the variation of the ionic radius. They were measurements of magnetization as a function of temperature with the vibrating sample magnetometer VSM of the Quantum Design, in temperature range from 50 to 310K. The curves of the magnetization as a function of temperature presented a similar behavior for all system.

Palavras-chave : cobaltite; structure crystalline; paramagnetic.

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