Using thermodynamic integration, we calculate free energies of the melt and the crystalline phases of a model system of C198H398 with a realistic all-atom potential. We use the Gibbs-Duhem integration scheme to calculate the melting curve over the experimentally relevant pressure range. The crystal structure and the melting curve obtained from our simulation are in good quantitative agreement with the available experimental results. (C) 2003 American Institute of Physics.