Fe Clusters in Fe Intercalated Fullerite

The local structure around Fe ions in the C$\text{}_{60}$Fe$\text{}_{2}$ fullerites before and after heat treatment in temperature of 850 K was investigated by means of Fe K edge X-ray absorption near edge structure and extended X-ray absorption near edge structure methods. The X-ray absorption measurements were performed at liquid nitrogen temperature using synchrotron radiation in transmission mode. The X-ray absorption near edge structure and extended X-ray absorption near edge structure studies showed that the heat treatment of the C$\text{}_{60}$Fe$\text{}_{2}$ fullerite at temperature 850 K causing an irreversible transition from monoclinic to fcc structure is accompanied with changes in the state of Fe ions, part of them forms clusters in bcc structure, while others turn to Fe$\text{}^{3+}$ ions bonded to fullerenes.