Effects of topology on the adsorption of singly tethered ring polymers to attractive surfaces.

We investigate the effect of topology on the equilibrium behavior of singly tethered ring polymers adsorbed on an attractive surface. We focus on the change of square radius of gyration R²g, the perpendicular component R²g⊥ and the parallel component R²g ‖ to the adsorbing surface, the mean contacting number of monomers with the surface {M}, and the monomer distribution along z-direction during transition from desorption to adsorption. We find that both of the critical point of adsorption ec and the crossover exponent f depend on the knot type when the chain length of ring ranges from 48 to 400. The behaviors of R²g, R²g⊥, and R²g ‖ are found to be dependent on the topology and the monomer-surface attractive strength. At weak adsorption, the polymer chains with more complex topology are more adsorbable than those with simple topology. However, at strong adsorption, the polymer chains with complex topology are less adsorbable. By analyzing the distribution of monomer along z-direction, we give a possible mechanism for the effect of topology on the adsorption behavior. [ABSTRACT FROM AUTHOR]