In a previous work we derived an equation for the radial distriubtion function g(r) for moleuclar liquids. It accounted for density correlations at both the monomer and molecular level. Here, it is shown that the theory canb e simplified to a form than allows it to be solved eaily by standard numerical methods. The theory is applied to charged, rodlke polymers with explicit counteions in solution near the idealized counterion condensation threshold (#lambda#_B/bapprox1, where #lambda#_B and b are the Bjerrum and chain bond length, respoectively). For densities above chain overlap, #rho)~*, it is found that the counteion cloud is diffuse about the polymer with a range on the order of the Debye-Huckel screening length. It is shown that the scaling with density of the first nonzero wave vector peak k_(max) of the polyemr-polymer partial structure factor agrees with experiment and previous theory, with k_(max)approx#rho#~* and vapprox=1/2 and 1/3, for densities above and below #rho#~*, repectively. It is also found that the ratio of the full width at half maximum of the peak, #DELTA#K, to k_(max) is a minimum near #rho#~*. On the other hand, for the counterion-counterion partial structure factor it is difficult to find any sharp scaling of k_(max) though the apparent exponent for the semidilute and a large part of the dilute region is roughly appromimated by v=2/5. Asymmetric solutions are also discussed.
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