MOLECULAR-DYNAMICS STUDY OF THE MELTING OF HEXAGONAL AND SQUARE LATTICES IN 2 DIMENSIONS

Simple pair potentials are discussed which give hexagonal- and square- lattice ground states in two dimensions. Molecular-dynamics calculatio ns for these potentials are used to study transitions between the two lattices and melting. The melting temperature is found to be a minimum near the point where the barrier between the two structures, as a fun ction of lattice strain, is also a minimum.