EFFECT OF WATER ON NITROGEN-FIXATION

clear. Among the various schemes, the intermediate water structure sch eme in the dinitrogen reduction to an ammonia was mainly investigated by inserting the water molecules around the chosen substrate, and the process of the dinitrogen reduction can be explained well on the basis of our schemes. The water molecules in the nitrogen fixation are not merely an inert or static environment but have an important role as in other biological systems. In our calculations, the model using 4H3O(4H2O+4H+) where these water molecules constitute a six-membered ring between the substrates shows the most reasonable results. This six-mem bered ring being composed of the water molecules with the nitrogen ato m upon the Fe atom of our substrate is slightly puckered to minimize t he energy and shows a significant process, and it can explain the nitr ogen fixation successfully. In these processes, 2H3O+ (2H3O+2 H+) and N2 are consumed to convert the dinitrogen into the diammonia together with producing the oxygen-related compounds. These oxygen-related comp ounds being a direct oxygen molecule or the peroxide molecules make it possible to interpret a lot of experimental evidences and to explain the processes of the nitrogen reduction successfully.