Configurational Entropy in k -mer Adsorption

Abstract

The general basis for accurate calculations of k-mer lattice gases' configurational entropy is presented. The method relies on the definition of an artificial Hamiltonian from the system of interest. By Monte Carlo calculation of mean total energy followed by thermodynamic integration from a reference state of the artificial Hamiltonian, the entropy of a state of interest can be obtained for the physical system under consideration. Entropy of interacting dimers (k = 2) and linear trimers (k = 3) on one- and two-dimensional regular lattices are shown. The entropy of bended (L-shaped) trimers is investigated as well. Interesting characteristics of the coverage and temperature dependence of entropy in these systems are displayed and discussed.