EXAFS study of mechanical-milling-induced solid-state amorphization of Se

Complete solid-state amorphization has been realized in elemental selenium by means of mechanical milling of crystalline Se powder. Extended X-ray-absorption fine-structure measurements (EXAFS) indicated that the amorphization process of crystalline Se was accompanied with a decrease of the nearest neighboring coordination number and the bond length, and the increase of the Debye-Waller factor. Combined with the previous study, we conclude that the mechanical milling results in the strengthening of intra-chain and weakening of inter-chain interactions of Se during amorphization. Compared to the structure of the as-quenched amorphous Se, the first nearest neighbor coordination number of the as-milled amorphous Se becomes smaller, while the Debye-Waller factor is larger, which is caused by the milling process. (C) 2004 Published by Elsevier B.V.