Performance of MOPAC on parallel computers

Key parts of the semiempirical MOPAC program package have been ported to pa rallel computers using the MPI message passing-library. Parallel routines a re available for the calculation of vibrational frequencies and electrostat ic potentials, as well as for energies of large biomolecules via the linear -scaling MOZYME self-consistent-held method. The parallelisation strategies used are discussed, and performance measurements for benchmark calculation s on three different parallel computers are presented. Frequency and ESP ca lculations show good scaling for up to eight nodes, independent of hardware and communications software. MOZYME calculations scale reasonably well if a fast implementation of MPI is available. (C) 2000 Elsevier Science B.V. A ll rights reserved.