The charge separation reactions for model systems containing an electron donor, D, and two electron accepters, A, in acetonitrile solvent at room temperature have been investigated. The electron transfer rate constants for A1-D-A2 and D-A1-A2 systems with various angular arrangements of the subunits are expressed in terms of the two-dimensional statistical distributions of the reaction coordinates, which are defined as the electrostatic potential difference between the respective pair of the reacting sites. These distributions have been evaluated by the MD computer simulation method. The dependence of the charge separation rate constant on the spatial arrangement of the subunits of the triad system, which arises from the present calculations, has been compared with the corresponding result obtained on the basis of the dielectric continuum model of the solvent. The dynamics of the reaction coordinates for both model systems has been characterized by the classical time autocorrelation and cross-correlation functions.