Surface Tension of Infinitely Planar Surfaces from Nucleation Free Energies: A Comparison of Monte Carlo Calculations and Classical Theories

A new approach for calculating the surface tension of an infinitely planar surface is presented, based on the thermodynamic relationship between clusters of different sizes. This method utilizes the aggregation-volume-bias Monte Carlo technique to compute the nucleation free energies of clusters of varying sizes. These free energy data are then compared with the predictions of conventional theories, such as classical nucleation theory and the Tolman equation, revealing that these theories accurately capture the size-dependency of the free energy for sufficiently large clusters. Key results from this analysis include the surface tension of an infinitely large cluster, corresponding to an infinitely planar surface, the Tolman length, and the chemical potential of the phases in equilibrium. The method is applied to two systems─Lennard-Jones and TIP4P/2005 water─and the calculated surface tension values for the infinitely large system (<i>γ</i>^∞) show excellent agreement with results from other established approaches.