title: Diffusion in the two-dimensional necklace model for reptation.
abstract: An extension of a recently introduced one-dimensional model, the necklace model, is used to study the reptation of a chain of N particles in a two-dimensional square lattice. The mobilities of end and middle particles of a chain are governed by three free parameters. This new model mimics the behavior of a long linear and flexible polymer in a gel. Noninteracting and self-avoiding chains are considered. For both cases, analytical approximations for the diffusion coefficient of the center of mass of the chain, for all values of N , are proposed. The validity of these approximations for different values of the free parameters is verified by means of Monte Carlo simulations. Extensions to higher dimensions are also discussed.
authors.affiliation: Institute of Materials Science and Technology (INTEMA), School of Exact and Natural Sciences, Universidad Nacional de Mar del Plata, Deán Funes 3350, B7602AYL Mar del Plata, Argentina.
authors.forename: G
authors.initials: G
authors.lastname: Terranova
authors.forename: C M
authors.initials: CM
authors.lastname: Aldao
authors.forename: H O
authors.initials: HO
authors.lastname: Mártin