Anomalous rotational relaxation: a fractional Fokker-Planck equation approach.

Phys Rev E Stat Nonlin Soft Matter Phys

Department of Physics, Faculty of Arts and Sciences, Dokuz Eylül University, Tr-35160 Buca, Izmir, Turkey.

Published: April 2005

In this study we have analytically obtained the relaxation function in terms of rotational correlation functions based on Brownian motion for complex disordered systems in a stochastic framework. We found out that the rotational relaxation function has a fractional form for complex disordered systems, which indicates that relaxation has nonexponential character and obeys the Kohlrausch-William-Watts law, following the Mittag-Leffler decay.

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http://dx.doi.org/10.1103/PhysRevE.71.046103DOI Listing

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