N2-H2O system was studied by ab initio SCF calculations with a 6-31G^*^* basis set. The resulted 200 data were fitted to an analytical function assuming pairwise additivity for the interaction between individual centres. The analytical functions were Lennard- Jones 10-6 and exponential form. A satisfactory fitting result was achieved by the simulated anneal algorithm. Special care was paid to repulsive region, which gives the important contributions to the formation of the first solvation shell of apoler solutes.

Key words: WATER, NITROGEN, COMPUTERIZED SIMULATION, AB INITIO CALCULATION