Band structure contribution of adsorbed H₂ on graphene calculated from molecular orbital projections

<p>Density functional theory allows for the first-principles calculation of projected wavefunctions onto orthogonalized atomic wavefunctions. Such calculations can be applied to study the bonding of a molecule onto an adsorbing surface. In particular, these projections allow one to identify the contributions of the adsorbed molecule to the band structure of the whole system. In this paper, we consider a system composed of an H₂ molecule adsorbed onto the hollow (H) site in a graphene 3x3 supercell.