Dynamical simulation of multicomponent carbon based materials
This thesis describes the simulation of important dynamical processes involving carbon based materials. Much of the research has been aimed at examining the properties of C6o (buckminsterfullerene), the recently discovered third allotrope of carbon. Classical Molecular Dynamics (MD) simulation has been applied to study such diverse processes as fullerene film growth, the interaction of fullerenes with graphite and bare and hydrogen terminated crystal surfaces, and the implantation of atoms within C6o. We have also studied radiation damage to polymers and graphite. Collaboration with experimentalists has resulted in realistic simulations being conducted to examine physical processes. The results of simulations have been able to explain experimental results and suggest alternative methods of achieving the goals of the experiment. Several algorithms designed to improve the efficiency of simulations have been programmed and tested. Timing results for these various algorithms are presented and the most successful have been incorporated into a new MD simulation code. This has enabled systems of up to 100,000 atoms to be studied in a realistic time using single workstations (e.g. IBM RS6000 and SUN Sparc-10). The interaction of atoms is modelled by many-body potential functions. Several potential fuctions that describe covalent systems have been programmed. New · potential functions have been produced to model the long-range interactions that occur in graphite, fullelite and polymer systems, and a three-component, manybody potential has been developed for the accurate and efficient simulation of carbon-silicon-hydrogen systems. Computer visualisation and animation techniques have been applied to the interpretation and display of simulation results.