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In this paper magnetic properties of six TiO 2 powders doped with 1, 5 and 10 mol% Fe and prepared by sol-gel method in two different ways were analysed. The size of the obtained TiO 2 :Fe particles was in the range 200-350 nm as it was confirmed by SEM and AFM techniques. The magnetization of nanopowders was measured as a function of temperature (1.8-300 K) and applied magnetic field. The samples with low Fe content manifest superparamagnetic dependence of magnetization. Whereas, the other compounds exhibit the paramagnetic behaviour with the negative Curie temperature, that suggests the antiferromagnetic ordering. Mass susceptibility decreased with the increase of Fe content as an effect of reduction of the mobility and number of charge carriers. The measurements showed that magnetic properties are correlated much stronger with the synthesis method than with the grain size.

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