International Workshop on Dynamics in Confinement

J. Phys. IV France 10 (2000) Pr7-207-Pr7-210
DOI: 10.1051/jp4:2000741

Water dynamics in controlled pore silica glasses

H.N. Bordallo¹, K.W. Herwig², W.D. Dozier³ and F. Drake<sup>4

1</sup>  Intense Pulsed Neutron Source, Bldg. 360, Argonne National Laboratory, Argonne, IL 60439, U.S.A.
²  Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831, U.S.A.
³  Fannie Mae, 3900 Wisconsin Ave. NW, Washington, DC 20016, U.S.A.
⁴  Exxon Research & Engineering Co., Route 22 East, Annandale, NJ 08801, U.S.A.

Abstract
Water in porous silica glass is a suitable system for investigating the effect of confinement on translational diffusion. These systems are important because of their relevance in catalytic and separation processes. Here quasi-elastic neutron scattering experiments at room temperature on water-filled controlled-pore glasses with radius of 15, 24 and 32Å, are presented and analyzed using the random-jump diffusion model. Both the average residence time and the mean jump distance increase with decreasing pore radius.

© EDP Sciences 2000