EQUATIONS OF STATE FOR SQUARE-WELL CHAIN FLUIDS USING THE GENERALIZEDFLORY APPROACH

The application of the Generalized Flory-Dimer theory (GFD) to square well chain fluids is described. Molecules are modelled as chains of ta ngent hard spheres that interact via a site-site square well potential u(r(ij)), where sites i and j are on different chains. The derivation of the GFD theory is reviewed; this is based on a combination of mean -field and geometric arguments. The resulting equation of state is in very good agreement with Monte Carlo computer simulation results for c hains of length n=16 and 32 at reduced temperatures T=2.0 and 3.0 and volume fractions eta=0.1 to 0.4.