THE EFFECT OF THE DISTRIBUTION OF VACANCIES ON THE MAGNETIC-PROPERTIES OF GAMMA-FE2O3 PARTICLES

Samples of gamma-Fe2O3 have been prepared from uniform alpha-Fe2O3 particles obtained by homogeneous hydrolysis in solution and directly by spray pyrolysis methods. The crystalline structure of these samples was analyzed by using x-ray and electron diffraction. It was concluded that, depending on the preparation method and parameters, different degrees of order in the distribution of vacancies were present. The study of the magnetic properties of these samples included the measurement of both intrinsic (saturation magnetization) and extrinsic properties (coercive force and magnetization behavior in the approach to saturation region). It was found that all the above-mentioned quantities depended on the degree of order in the distribution of vacancies.