Massively Parallel Density Functional Theory Calculations of Large Transition Metal Clusters

We report on ab initio density functional theory (DFT) calculations of structural properties of large elementary transition metal clusters with up to 561 atoms, corresponding to a diameter of about 2.5 nm, which is a relevant size for practical applications. The calculations were carried out on an IBM Blue Gene/L supercomputer, showing that reasonable scaling up to 1024 processors and beyond can be achieved with modern pseudopotential plane wave codes.