The Fractal (BSf) Kinetics Equation and Its Approximations

Abstract

We discuss the Brouers-Sotolongo fractal (BSf) kinetics model. This formalism interpolates be-tween the first and second order kinetics. But more importantly, it introduces not only a fractional order n but also a fractal time parameter a which characterizes the time variation of the rate con-stant. This exponent appears in non-exponential relaxation and complex reaction models as dem-onstrated by the extended use of the Weibull and Hill kinetics which are the two most popular ap-proximations of the BSf (n, a) kinetic equation as well in non-Debye relaxation formulas. We show that the use of nonlinear programs allows an easy and precise fitting of the data yielding the BSf parameters which have simple physical interpretations.