Diffusion of linear polymers in a gel

G. TERRANOVA, H.O. MÁRTIN, Y C.M. ALDAO

Mar del Plata, Argentina

Congreso; XV Conference on Nonequilibrium Statistical Mechanics and Nonlinear Physics (MEDYFINOL 2006); 2006

An extension of a recently introduced one-dimensional hard-core repton model is used to study the diffusion of a chain of  N  particles in two dimensions. The mobilities of end and middle particles of a chain are governed by three free parameters. This new  model represents the behavior of a long linear and flexible polymer (such as a DNA) in a gel. The cases of nointeracting and self avoiding chains are considered. In the asymptotic limit (Nƕ) and for both cases, it is found that the diffusion coefficient   D  behaves as  D ~ N 2n-3, where n  is the end-to-end distance  exponent of the chains.  For the nointeracting case, an analytical approximation of  D  for all values of  N  is proposed.  The validity of this approximation for different values of free parameters is verified by means of Monte Carlo simulations.