RISM and liquid state integral equation theories
Integral equation liquid state
theories have a long history in statistical mechanics, starting with John Kirwood in 1935 (see the textbook by McQuarrie for more). In the
case of molecular liquids, the Reference Interaction Site Model (RISM) developed by David Chandler in the 1970's
with the Percus-Yevick or hypernetted chain (HNC) closure is a simple and often useful
approximation for calculating solvent radial distribution function, potential of mean force,
and excess chemical potentials. Here you will find a fortran program (rism.f) with some examples
of input files to carry such calculations.