(222aq) Segmental Chemical-Potential Increments for Polymeric and Polyatomic Fluids: A Potential Distribution Based Investigation

Segmental chemical-potential increments for polymeric and polyatomic fluids: A potential distribution based investigation.

We apply the three potential distribution theorems derive earlier [1] [2] to the characterization of the segmental increase of the chemical potentials for chain molecules. Both tangent hard-sphere chains and Lennard-Jones chains are investigated.  We define the conditional singlet direct correlation functions as the incremental works of insertion of successive segments of the molecule.  By employing Monte Carlo data, we arrive at a quantitative evaluation of the chemical-potential increments of the initial mers, and a clear demonstration of the non-congruent nature of first segments of a polymer.  We suggest a purely geometrical obstruction theory that accounts for 90% of the non-congruence.

[1].. L. L. Lee, The correlation functions of classical fluids III.  The method of partition function variations applied to the chemical potential: cases of PY and HNC2, Journal of Chemical Physics 60, 1197 (1974).

 [2] L.L. Lee, A potential distribution approach to fused heterochain molecules. I. Mixtures of hard dumbbells and spheres Journal of Chemical Physics, 103, 4221-4233 (1995).