Modeling the Effect of Oxidation on Magnetic Characteristics of Magnetith Nanoparticles

The theoretical analysis of the influence of oxidation processes on the blocking temperature and hysteresis characteristics of a system of magnetite nanoparticles was carried out. It is shown that the blocking temperature drops sharply at the initial stage of the maghemization process and practically does not change with an increase in the proportion of maghemite in the region 0,4 < < 1. In addition, it has been found that the spontaneous saturation magnetization decreases with increasing oxidation state of nanoparticles, while magnetite oxidation leads to an insignificant decrease in the coercive force and the ratio of the residual saturation magnetization to the saturation magnetization.