Large-scale ab initio total energy calculations on parallel computers

An implementation of a set of total energy plane-wave pseudopotential codes on a parallel computer is described which allows calculations to be performed for systems containing many hundreds of atoms in the unit cell. Possible parallelisation strategies are discussed and it is shown that assigning parts of real and Fourier space across the processors is the least restricted approach. The performance of our parallel codes is demonstrated by timing tests carried out on several i860-based parallel machines and these are compared with tests performed on conventional sequential supercomputers. Ab initio computations on systems which are beyond the power of conventional supercomputers as well as ew perspectives for first-principles molecular dynamics are discussed.