Hannes Jonsson is supported by a grant from the Theoretical and Computational Chemistry Program to continue his research in the development of computer algorithms for density functional theory simulations and applications to semiconductor crystal growth. Jonsson will parallelize his own methods for finding minimum energy paths and transition state activation barriers. He will also investigate free energy barriers which include anharmonicity, and algorithms which scale linearly with system size. His applications will focus on interpretation of current imaging experiments by calculating adatom diffusion rates and surface cluster formation rates for industrially relevant systems such as silicon and silicon carbide surfaces, germanium-silicon interfaces, and silicon dioxide overlayers. Modern density functional theoretical methods will be developed and used to study a variety of surface growth mechanisms of technological importance. In particular these methods will be extended to enable the study of larger, more complex models of materials on new and emerging massively parallel computers. The methods involve the sophisticated evaluation of accurate energetics for a number of complex atomic-scale processes on semiconductor surfaces.
