Surface tension of hard core Yukawa fluid

The statistical mechanical expression of Fowler for the surface tension is reformulated for a hard sphere Yukawa fluid within the mean field approximation to obtain an analytical solution. This allows an investigation of the role of long-range interactions and the effect of temperature on the surface tension. For the atomic density profile at the surfaces, the liquid-vapour coexistence curves were reproduced, and hence the rectilinear density was used as the average density at the surface. The results suggest that the surface tension and its temperature gradient are quite sensitive to the long-range interactions.