Abstract:

A modified Monte Carlo method combined with quenched molecular dynamics simulation is used to determine mixing energetics and concentration profiles at interface for systems containing mono-and bilayers of adatoms adsorbed on FCC (100) crystal surface. The systems under consideration are constructed via Lennard-Jones potential at temperatures near 0 K. For systems with monolayer of adatoms, intermixing at the interface becomes preferable with increasing magnitude of the potential well-depth ratio of adatom to substrate atom. The increasing tendency of intermixing is linearly enhanced when the adatom becomes smaller than the substrate atom, otherwise, the intermixing trend is non-linear and weaker. For systems with bilayers of adatoms, complex development of concentration profile is observed along with increasing magnitude of the potential well-depth ratio and atomic size difference between adatom and substrate atom. This behaviour is related to the interplay between contributions of asymmetric bond interaction and relaxation to minimise the total energy of the system.

Keywords: interfacial mixing; FCC thin film and substrate; Monte Carlo simulation; molecular dynamics

Document Type: Research article

DOI: 10.1080/00268970802502527

Affiliations: 1: Division of Chemical and Biomolecular Engineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 2: Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur, India