Deuterium nuclear magnetic resonance studies of the molecular dynamics of benzene in zeolites

Abstract

Deuterium n.m.r. spectroscopy has been used to investigate the microdynamics of benzene molecules sorbed on HZSM-5, NaX and NaY zeolites. As in the liquid and solid benzene phases, the sorbed benzene molecules perform fast reorientations about their hexad axes. Superimposed on this C₆ reorientation are jumps which the benzene molecules perform between the sorption sites. The mean residence time between two succeeding jumps depends significantly on the zeolite framework, the temperature and the loading. From this finding, diffusivities of sorbed benzene molecules can be estimated.