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arXiv · 1301.7716

Cobalt Substitution in CuFe$_{2}$O$_{4}$ spinel and its influence on the crystal structure and phonons

M. D. P. Silva·F. C. Silva·F. S. M. Sinfrônio·Alexandre Rocha Paschoal·E. N. Silva·Carlos William de Araujo Paschoal
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Abstract

In this work nanometric spinel Co${}_{1-x}$Cu${}_{x}$Fe${}_{2}$O${}_{4}$ powders were obtained by polymeric precursors method at several annealing temperatures between 700 and 1200 ${}^\circ$C. The samples were characterized by means of X-ray powder diffraction, confirming the ideal inverse spinel structure for CoFe${}_{2}$O${}_{4}$ sample and the tetragonal distorted inverse spinel structure for CuFe${}_{2}$O${}_{4}$ sample. Based on FWHM evaluation, we estimated that crystallite sizes varies between 27 and 37 nm for the non-substituted samples. The optical-active modes were determined by infrared and Raman spectroscopies. The phonon spectra showed a local tetragonal distortion for mixed samples.

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M. D. P. Silva, F. C. Silva, F. S. M. Sinfrônio, Alexandre Rocha Paschoal, E. N. Silva, Carlos William de Araujo Paschoal. 2013-01-31. Cobalt Substitution in CuFe$_{2}$O$_{4}$ spinel and its influence on the crystal structure and phonons. https://arxiv.org/abs/1301.7716

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