Polarizable water models: Vectorization of energy calculations on the CYBER 205

Abstract A large fraction of the time spent calculating the energy of a configuration of polarizable water molecules is spent calculating the electric field and polarization energy. This paper describes vectorization strategies for such calculations on the CYBER 205. For a cluster of 215 waters and the Lybrand-Kollman model, the vectorized calculation on the CYBER 205 executes at about 47 times VAX 8650 speed, or about 300 times VAX 11/780 speed.