الملخص

In order to study the practicability delimitating the optimal electrical properties have been studied for soft ferrite system Mg(|. x)MnxFe20.4 , which prepared by solid state method in the temperature range 300 to 550 K by substituting Mn2+ ions instead of Mn2+ ions. The resulting of this study shows that the electrical conductivity for these systems were optimal value (10"7) The calculation of activation energy gave of 0.224 eV and 0.243 eV. The positive sign of thermoelectric power (seeback coefficient) for these samples at lower concentrations of substitution Mn2+ ions , and negative sign of at higher concentrations of substitution Mn2+ ions. Also the optimal magnetic susceptibility properties resulted in values -86x10" j -622x10". From the electrical properties (electrical conductivity and thermoelectric power) and magnetic susceptibility, the optimal results where obtained with x~ 0.1 for Mn2+ ions.