A study was made, of the melting of a face-centered cubic crystal, by using isobaric-isothermal Monte Carlo simulations and a Lennard-Jones potential. The results showed that defects which were created in the solid phase became numerous enough to cause the crystal to melt. At the transition, some 25% of the sites had a coordination number of 12. When just above the transition, only some 20% of the sites had 12 nearest-neighbours. An analysis of the defect’s structure showed that it was surrounded by atoms at a distance which was equal to about 71% of the nearest-neighbour distance, and by other atoms at a distance which was about 14% greater, and was not the next-nearest neighbour distance. These atoms were themselves created by distorting atomic positions. The latter corresponded to so-called bridge positions in the potential landscape.

Monte Carlo Simulation of the Role of Defects as a Melting Mechanism. L.Gómez, A.Dobry, H.T.Diep: Physical Review B, 2001, 63[22], 224103 (6pp)