MELTING AND FREEZING IN TWO DIMENSIONS: A MOLECULAR DYNAMICS STUDY.

Using the molecular dynamics (MD) technique, the authors have investigated the nature of melting and freezing transitions as well as structural and dynamical properties of liquid and solid phases in two-dimensional systems interacting via l/r and l/r**3 potentials. From the velocity auto-correlation function (VAF) and dynamic structure factor for the electron liquid, it is shown that the well-defined oscillations in VAF are due to a coupling between the single particle motion and longitudinal excitations of wavevector on the order of inverse interparticle separation. The melting transitions are investigated by calculating the temperature dependence of internal energy and constant of self-diffusion. The effect of size of the MD system and length of calculations are investigated systematically.