Phase diagram of Yukawa systems near the one-component-plasma limit revisited

Transition inverse temperatures (or Gamma values) at the fluid-solid phase boundary of Yukawa systems near the one-component-plasma (OCP) limit have been evaluated by molecular dynamics simulations. These values are systematically smaller than those obtained in an earlier study by Farouki and Hamaguchi [J. Chem. Phys. 101, 9885 (1994)]. The discrepancy is attributed to the fact that, in the earlier study, the harmonic entropy constants were approximated by that of the OCP, whereas the new results are based on more accurate harmonic entropy constants obtained from lattice-dynamics calculations. The new molecular dynamics simulations also confirm that the bcc-fcc phase transition curve is in good agreement with that of the quasiharmonic theory in the regime kappa less than or equal to 1.4, where kappa is the ratio of the Wigner-Seitz radius to the Debye length. Examples of Yukawa systems include dusty plasmas and colloidal suspensions. (C) 1996 American Institute of Physics.