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arXiv · 1302.5876

Superparamagnetic Transition and Local Disorder in CuFe2O4 Nanoparticles

G. F. Goya·H. R. Rechenberg
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Abstract

We present X-ray diffraction (XRD), M\"ossbauer spectroscopy (MS) and d.c. magnetization measurements performed on ball-milled CuFe2O4 samples. The average particle size was found to decrease to the nanometer range after t=15 min of milling. Room temperature M\"ossbauer data showed that the fraction of particles above the blocking temperature TB increases with milling time, and almost complete superparamagnetic samples are obtained for = 7(2) nm. Magnetization measurements below TB suggest spin canting in milled samples. The values of saturation moment mu_S reveal that site populations are slightly affected by milling. M\"ossbauer resonant intensities are accounted for on the basis of local disorder of Fe3+ environments, and the development of sample inhomogeneities of CuxFe3-xO4 composition.

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G. F. Goya, H. R. Rechenberg. 2013-02-24. Superparamagnetic Transition and Local Disorder in CuFe2O4 Nanoparticles. https://doi.org/10.1016/s0965-9773(98)00133-0

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