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Volume 117, Issue 4, 22 July 2002
117(2002); http://dx.doi.org/10.1063/1.1494425View Description Hide Description
We apply a Monte Carlo technique specialized for the simulation of rare events to study the activated counterions motions in the aluminosilicate -mordenite. Mean activation barriers are obtained from minimum energy paths calculated on realistic potential energy surfaces by using a Metropolis algorithm. Energy barriers for hops calculated for lattices with various Si/Al ratio are found in good agreement with the detrapping energiesmeasured by thermally stimulated current spectroscopy. One shows that the dielectric activated motions of proceed between degenerated many-body ground states with different dipolar moment by either sequential or collective hopping motions. This provides a first microscopic description of dielectric relaxationmeasured in zeolites.