Crystallization of the one-component plasma at finite temperature

We have determined the coexistence at positive temperature between a Wigner crystal and a fluid plasma using path integral Monte Carlo. The total energies are significantly different from classical and semiclassical predictions. The location of the phase transition between liquid and solid is higher in temperature than predicted by a generalized Lindemann criterion. Some features of the phase diagram can be understood using a novel application of the Clausius-Clapeyron equation. We find a maximum melting temperature of 6.0(5) × 10^-5 Ry at r_s = 180(20).