ac electrical conductivity and dielectric behavior of nanophase nickel ferrites

The electrical properties of nanocrystalline nickel ferrites having general chemical formula NixFe(3-x)O4 have been studied. The ac electrical conductivity has been measured as a function of frequency in the range 50-900 kHz at room temperature 296 K. The conductivity was found to increase with frequency due to the hopping mechanism of electrons. The dielectric constant and loss tangent were calculated for different frequencies. (C) 2007 Elsevier B.V. All rights reserved.