DIFFUSION OF NITROXIDE SPIN PROBES AT THE ALUMINA CYCLOHEXANE INTERFACE/

The diffusion of adsorbed paramagnetic spin probes at the solid-liquid interface was studied using electron spin resonance spectroscopy (ESR ) with 7-doxyl stearic acid as the probe. The changes in the localizat ion of these probes at the interface was monitored by variations in th e spin exchange line broadening of the ESR spectrum, These studies rev ealed that the introduction of fresh adsorption sites or a competing a dsorbate causes a redistribution of the probe, However, temperature wa s found to have no significant effect on the probe localization. (C) 1 996 Academic Press, Inc.