We compute the internal energy of the classical one-component plasma, for values of the Coulomb coupling parameter $\Gamma$ between 1 and 300, by using converged Monte Carlo chains and a more accurate potential approximation than that used by Hansen. The liquid data are fitted to a simple, very accurate four-parameter formula from which the Helmholtz free energy is derived. The solid data are likewise fitted to a one-parameter formula. The intersection of the two free-energy curves gives an estimate of the fluid-solid transition at $\Gamma =168\mathrm{}\pm 4$.

• Received 28 August 1979

DOI:https://doi.org/10.1103/PhysRevA.21.2087