Hydrogen bonding in diamond: A computational study

We present tight binding molecular dynamics simulations of the diffusion and bonding of hydrogen in bulk diamond. The motion of hydrogen atoms and the resultant structural and electronic energy level changes axe investigated. The hydrogen atoms were found to have a tendency to migrate to the surface layer of diamond, resulting in a local deformation of the lattice, creating new energy states above and below the Fermi energy in the bandgap of the diamond density of states. In the diamond bulk, at high hydrogen concentrations, vacancies created by a hydrogen atom are quickly filled with other hydrogen atoms causing a deformation of the diamond lattice, inducing H-2 formation. This creates new energy states above the Fermi energy and reduces the secondary bandgap of the diamond density of states.