  A new approach to thermodynamics of simple fluids is presented. The partition
function is first expressed in the reciprocal space, it is argued that the
links (p,q) between 2 molecules can reasonably in the thermodynamical limit be
considered as a set nearly independent objects characterized by the dynamical
variables . It is then possible to derive an expression of the pair correlation
function. The results, which are independent of the exact shape of the
intermolecular potential, are applied to the simple case of hard sphere fluids.
