DIFFUSION IN A FLUCTUATING RANDOM GEOMETRY

A theoretical analysis is presented of the self-diffusion of a particl e in a disordered and fluctuating one-dimensional geometry. A general result is obtained, showing how geometrical fluctuations enhance the r ate of diffusion measured in a laboratory-fixed frame. This result is relevant for understanding molecular transport in certain complex flui ds and biological systems. Explicit results are given for three differ ent dynamic models, illustrating how diffusion measurements can be use d to extract information about the orientational distribution and dyna mics of segments of polymers or wormlike micelles in isotropic solutio ns and liquid-crystalline phases.