Wang-Landau Simulations of Adsorbed and Confined Lattice Polymers

Abstract

We demonstrate how Wang-Landau simulations may be used in an effcient manner to investigate the statistical mechanics of lattice polymers adsorbed at a planar surface, and confined in slit geometry between two parallel surfaces. For nearest neighbour interactions, we show that one or two Wang-Landau simulations, recording the density of states as a function of numbers of internal contacts and of surface beads, are suffcient to give a full description of both of these situations. Moreover, the effciency of the simulations is improved by never having to reject moves due to overlap with the surface, and the limit of infinite slit height may be handled easily. The proposed “wall-free” methods have already been applied to homopolymers and heteropolymers (lattice peptides using the HP model) on a uniform surface, as well as regularly patterned surfaces, and could easily be generalized to surfaces with structure.