Monte Carlo Study of the Thermodynamics of Electrolyte Solutions

Monte Carlo techniques have been used to study the primitive model of an ionic solution. The parameters chosen correspond to a simple 1:1 electrolyte dissolved in water at 25°C. Data are derived for the pair distribution functions, excess internal energy and heat capacity, osmotic coefficient, and mean activity coefficient, in the range 0.01–2M. The results are compared with a nonlinear form of the Debye–Hückel theory and with integral equation results in the Percus–Yevick and hypernetted chain approximations. The last appears to be excellent up to $\text{1M}$ .