الفهرس 
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Abstract
nano iron ferrite. Magnetite has been synthesized employing the coprecipitation technique where a substitution exchange interaction occurs. X-ray structural investigations have been applied to confirm the crystal structure of the precipitate. from X-ray analysis the magnetite crystal structure, the crystallite size, the lattice parameters were evaluated.
To study electrical properties of magnetite, disk shaped samples were used to measure the electrical resistivity at room and elevated temperatures up to 670 K.
Calculations based on the magnetic moment and the lattice constants were performed using Mathcad program. from these calculations a cation distribution for magnetite was suggested. According to the cation distribution the Fe+2 and Fe+3 ions are located in either the tetrahedral (A-site) or octahedral (B-site) or both sites, taking the spin into account, the total magnetic moment and the magnetic moments of both the octahedral and tetrahedral sites were calculated.
For investigating the electronic band structure of magnetite, density functional theory was applied utilizing Win2k code and linearized augmented plane wave (LAPW) method. Structural optimization, spin, Oxygen position were taking into consideration. Once the minimum energy is achieved, the density of states, charge distribution, band structure and optimized crystal structure will be inspected.
from the DOS data the contribution of spin up and spin down to the conduction electrons is scrutinized. In addition the occupation of the tetrahedral and octahedral sites are inspected. Moreover, from the DOS and band structure calculations, the behavior of magnetite can be resolved either conductor, semiconductor or half metallic.
A correlation between the results of the theoretical study and the calculations based on the experimental data will be given and contemplated