Probing the nano-scale with first-principles calculations

The fabrication of materials and structures with nano-scale features holds great promise for the realization of systems with novel physical properties and enhanced functionality. Here we review results from first-principles calculations on nano-structures and demonstrate some of the current capabilities for the use of computer simulations as an explanatory or predictive tool of nano-science. We discuss results on the possibility of achieving encapsulation of floating carbon nanotubes in a dielectric medium. We also present results on isomerization kinetics of silicon clusters and examine ways of functionalization of silicon or metallic surfaces by organic molecules. We finish with a discussion on the formation of gold nanowires and molecular break junctions through pulling of Au electrodes.