Density distribution for the molecules of a liquid in a semi-infinite   space
  The Sutherland approximation to the van der Waals forces is applied to the derivation of a self-consistent Vlasov-type field in a liquid filling a half space, bordering vacuum. The ensuing Vlasov equation is then derived, and solved to predict the behavior of the density at and in the vicinity of the liquid-vacuum interface. A numerical solution to the Vlasov equation is also produced and the density profile shown and discussed. 
V. Molinari, B.D. Ganapol, D. Mostacci
cond-mat.soft