Magnetic Properties of Molecular p-d System l-(BEDT-STF)2FexGa1-xCl4

The purpose of this proposal is to reveal the mechanism of the peculiar magnetism observed in molecular p-d system l-(BEDT-STF)2FexGa1-xCl4, where BEDT-STF is bis(ethylenedithio)diselenadithiafulvalene. l-(BEDT-STF)2FexGa1-xCl4 shows a peculiar magnetic property that the local fields at Fe sites show a step-like development below an antiferromagnetic transition temperature (TN). The mechanism of the peculiar magnetism is considered to be derived from the magnetic coupling between p electrons with strong electron correlation and localized 3d spins. In this proposal, we investigate the Fe concentration dependence of the TN and the local fields at Fe sites. By controlling the Fe concentration, we can modulate the strength of the magnetic coupling systematically. From the results, we discuss the relationship between the coupling effect and the mechanism of the peculiar magnetism.