LATTICE FIELD-THEORY FOR SPHERICAL MACROIONS IN SOLUTION - CALCULATION OF EQUILIBRIUM PAIR CORRELATION-FUNCTIONS

A recently developed lattice field theory (LFT) formulation of the sta tistical mechanics of a classical Coulomb gas interacting with a fixed charge distribution [J. Chem. Phys. 97, 5653 (1992)] is utilized to c ompute equilibrium pair correlation functions, g(r), of aqueous suspen sions of charged spherical macroions (''polyballs''). These results ar e compared to the predictions of the widely used Derjaguin et al. (DLV O) theory. In, addition an effective pair potential for the colloid-co lloid interaction is obtained by applying the LFT approach to a two-co lloid system. This pair potential is then used in a many-colloid simul ation to obtain g(r). Ah simulations are performed using the Metropoli s Monte Carlo procedure together with the appropriate interpolyball po tential function. Even in the regime in which a pair potential descrip tion might be expected to be adequate, differences exist between the L FT and pair potential results.