Magnetic properties of g-Fe2O3 dispersed particles: size and matrix effects

Static properties (0–5.5T, 2–300K) of g-Fe2O3 5- and 9-nm particles trapped in a silica xerogel (Fe/Si=0.01-0.44mol/mol) give evidence of strains. Comparing with dispersions in a polyvinylic alcohol suggests that the temperature dependence of the coercivity could reflect an intrinsic interparticle interaction effect.