Two-phase coexistence in the hard-disk model
  A two-dimensional system of 10000 hard disks with square periodic boundary conditions, at a density in the middle of the 2-phase region predicted from equation-of-state data, when subjected to a weak external uniform force, is seen to phase separate. Thermodynamic profiles of the inhomogeneous two-phase system agree with the local density approximation (LDA) of density functional theory. There is no indication of any mesophase. 
Leslie V Woodcock