Homogeneity and Size Effects on the Liquid-Gas Coexistence Curve

The effects of (in)homogeneity and size on the phase diagram of Lennard-Jones fluids are investigated. It is shown that standard multifragmentation scenarios (finite equilibrated systems with conserved center of mass position and momentum) are implying a strong radial inhomogeneity of the system strongly affecting the phase diagram. The homogeneity constraint is therefore necessary for finite systems in order to align to the ``meaning'' of infinite systems phase diagrams. In this respect, a method which deduces the equation of state of homogeneous finite systems from the one corresponding to bulk matter is designed. The resultant phase diagrams show a strong dependence on the system's size.