Spin canting observation and cation distribution in CoFe_(2-x)In_xO_4(0.0 ≤ x ≤1.0) ferrites through low temperature-high field Mossbauer spectral study

摘要

In the present work, In~(3+) substituted cobalt ferrites (CoFe_(2-x)In_xO_4, x = 0.0,0.2, 0.4,0.6, 0.8,1.0) have been synthesized via solid-state reaction technique. The Rietveld fitted X-ray diffraction patterns confirm the formation of single phase cubic spinel structure with space group Fd3m for all the samples, with additional slight traces of secondary phase for x = 0.6, 0.8 and 1.0 samples. The low temperature (5 K)-high field Mossbauer (5T) spectra are analyzed in detail for probing the magnetic properties of Fe based In~(3+) substituted cobalt ferrites. The canted spin structures associated with Fe~(3+) ions both at A- and B-sites in the presence of external magnetic field of 51 have been noticed in all the samples. A fair agreement is obtained between the experimental integrated intensity ratios of ~(57)Fe Mossbauer spectra at A- and B-sites and those calculated on the basis of cation distribution. The effect of In~(3+) substitution on various Mossbauer parameters viz hyperfine field distribution, isomer shift, quadrupole splitting and the line width has also been noticed. The magnetization measurements performed at low temperature also reveal the canted spin structures in all the samples. The variations in initial permeability over a wide range of frequency (125 kHz-30 MHz) at 300 K have also been recorded. The initial permeability study reveals the occurrence of resonance phenomenon at very high frequencies which widens the area of utility of considered ferrites in the larger operational frequency range for various industrial applications.