الفهرس 
Chapter two: Experimental WorkOnly 14 pages are availabe for public view
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Abstract
Sol-gel auto-combustion synthesis technique was employed to synthesize Cd-
Zn ferrite nanoparticles with the chemical composition CdxZn1-xFe2O4, where
0.0 ≤ x ≤ 1.0. The physical properties of prepared samples were inspected by using x-
ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform
infrared spectroscopy (FTIR), vibration sample magnetometer (VSM) techniques and
broadband dielectric spectroscopy (BDS). XRD analysis confirmed the formation of
Cd-Zn spinel nano-ferrites with an increase in experimental lattice constant from 8.37
Å to 8.74 Å for ZnFe2O4 and CdFe2O4 samples, respectively. Variation of tetrahedral
and octahedral hopping lengths, crystallite size, micro-strain and dislocation density
with Cd-content has been investigated and elucidated. SEM micrographs showed
agglomeration of nearly spherical grains that increased in size with Cd-content
increase. FTIR analysis confirmed the existence of the characteristic tetrahedral and
octahedral stretching vibrations of metal ion and oxygen complex in the range 429–
558 cm−1. VSM measurements revealed a tuning in coercivity to higher values and a
decrease in saturation magnetization as Cd-content increased. The calculated cations
distribution, bond lengths, bond angles and interionic distances between cations at
tetrahedral and octahedral sites attribute the observed decrease in saturation
magnetization to weak interaction between cations in the two sites. Dielectric
measurement demonstrates the relation between the dielectric constant, Dielectric
loss tangent, conductivity and Cole-Cole complex impedance with increasing
frequency at room temperature