Regensburg 2004 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
CPP: Chemische Physik und Polymerphysik
CPP 5: Computational Physics
CPP 5.1: Vortrag
Montag, 8. März 2004, 10:00–10:15, H 39
Numerical Studies of Tethered Chains at Adsorbing Surfaces — •Radu Descas1, Jens-Uwe Sommer2, and Alexander Blumen1 — 1Theoretische Polymerphysik, Univesität Freiburg — 2Institut de Chemie des Surfaces et Interfaces, Mulhouse Cedex
We present extensive Monte Carlo simulations of tethered chains on adsorbing surfaces, considering the dilute case in good solvents, and analyze our results using scaling arguments. We focus on the mean number of chain contacts with the adsorbing wall, on the chain extension (the radius of gyration) perpendicular and parallel to the adsorbing surface, on the probability distribution of the free end and on the density profile for all monomers. For the cross-over from non-adsorbed to adsorbed behavior we obtain best results using a cross-over exponent of 0.59. We also investigate the dynamical scaling behavior at the critical point of adsorption, considering the end-to-end correlation function and the correlation function of adsorbed monomers at the wall. We find that the dynamic scaling exponent a (which describes the relaxation time of the chain as a function of its length) is the same at the adsorption threshold as that of free chains. Moreover, we find that tethered chains relax quicker perpendicularly to the wall than parallel to it.