1301.7716 (M. D. P. Silva et al.)

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

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

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.

View original: http://arxiv.org/abs/1301.7716