A microscopic theory for spherical interfaces: Liquid drops in the canonical ensemble

We have studied the interfacial properties of droplets of (cutoff and shifted) Lennard-Jones fluids in the canonical ensemble, using mean field theory. We have examined the effects of system size, overall density (supersaturation) and temperature on the density profiles, density and pressure at the center of the droplet, and surface tension. The numerical accuracy of the theory was tested by extensive comparisons of the results with the molecular dynamics simulations of Thompson et al. Good agreement was found. We have used the theory to calculate the energy of formation of a droplet and the stability temperature Ts for droplet formation as a function of the system size and overall density. We find Ts to be lower than the coexistence temperature for the planar surface, and to fall as the drop size falls.