Fe Clusters in Fe Intercalated Fullerite

E. Sobczak, D. Żymierska, P. Byszewski, A. Traverse
1997 Acta Physica Polonica. A  
The local structure around Fe ions in the C60Fe2 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
more » ... showed that the heat treatment of the C60Fe2 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 Fe3+ ions bonded to fullerenes. PACS numbers: 71.20.Tx, 61.46.+w, 61.10.Ht The development of fullerene chemistry and technology, and resulting possibility of chemical modifications create new research and applications perspectives. Some investigations of the structure, metal-fullerene bonding and interaction between Fe and C60 [1-6] have been reported. An original method of preparation of C60Fe2 fullerite by decomposition of ferrocene in solid fullerite has been elaborated by Byszewski et al. [3] . Recently, we have reported some results of X-ray absorption studies of monoclinic C 60 Fe2 fullerite, which have shown that the local structure around Fe ion in the monoclinic C60Fe2 fullerite is almost identical to that of ferrocene and that neither a remarkable amount of Fe metallic clusters nor oxidized iron particles were present in the monoclinic C60Fe2 sample [8] . The aim of our studies is to reveal the changes in local structure of Fe ions sites in C60Fe2 fullerite due to heat treatment at temperature 850 K, accompanied with the irreversible transition of monoclinic structure to fcc structure [6] . We carried out the X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) measurements for the C60Fe2 fullerites and few other Fe compounds by using synchrotron radiation. The monoclinic C60Fe2 fullerite was prepared in the powder form by the decomposition of ferrocene Fe(C5H5)2 molecules in solid fullerite at temperatures (447)
doi:10.12693/aphyspola.91.447 fatcat:olwx2kquk5grxpewc23hiufche