COMPUTER-SIMULATION OF CLUSTER DECAY

Lennard-Jones metastable clusters consisting of 5 to 1030 atoms have been studied by molecular-dynamics simulation. Evaporation rate constants and caloric equations of state have been obtained in the microcanonical ensemble and with the use of RRK theory of unimolecular reactions and a local har-monicity approximation the canonical rate constants have been evaluted. The comparison with classical nucleation theory, specifically with the liquid-drop model, shows that the calculated equilibrium vapour pressure is significantly higher than theoretical one for small clusters, whereas the micro-canonical results agree with theory. © 1990 Taylor & Francis Ltd.