Spin glass behavior in complexes of iron doped coordinated polymers

Magnetization measurements were performed on metal polycarbosilazane complexes polymers doped with Fe(II) and Fe(III)-ions. Zero field cooled (ZFC) and field cooled (FC) magnetization for Fe(II) doped polymer were found to bifurcates at a freezing temperature Tg, showing typical spin glass behavior but at much higher fields (∼kOe) than what is commonly observed in metallic spin glass(∼Oe). However, the ZFC magnetization of Fe(III) doped polymer did not reveal any spin-glass behavior. The magnetization curves showed very little Hysteresis effects and saturate at about 40 kOe at 2 K then drops sharply at 20 K. The saturation magnetization continues to drop gradually up to room temperature ∼300 K.