T0501-2-3 Dissociative Adsorption Probability Model of the H_2-Pt(111) System Based on Molecular Dynamics

Abstract

Molecular Dynamics (MD) was used to simulate dissociative adsorption of hydrogen molecule on Pt(1l1) surface considering the movement of the surface atoms and gas molecules. Embedded Atom Method (EAM) was applied to represent the interaction potential. A number of MD simulations of gas molecules impinging on Pt(111) surface were carried out changing initial orientations, incident azimuth angles, and impinging positions on the surface using uniform random numbers with fixed initial translational energy, initial rotational energy, and incident polar angle. The number of incidents that dissociated gas molecules was counted to compute dissociation probability. The dissociation probability was analyzed and expressed by a mathematical function of initial conditions of impinging molecule, namely translational energy, rotational energy, and incident polar angle. And the model was verified by comparing with MD simulation results of molecular beam experiments.