The Isolated Se Chains in the Channels of Mordenite Crystal

Abstract

The measurements of the extended X-ray absorption fine structure and the photoacoustic spectroscopy have been carried out for Se chains confined in the channels of synthetic mordenite with about 6.7 A diameter. The first-nearest Se–Se distance in mordenite channels is 2.32 A, shorter than that in crystalline Se. The absorption edge for Se adsorbed in the mordenite channels lies at shorter wavelength than that for amorphous Se. This suggests that the covalent bonds along the Se chain become stronger when the coupling between adjacent Se chains is reduced. It is found that the isolated Se chains in the mordenite channels are strongly photo-sensitive.