From the energies of the optimized structures, reaction energies between the intermediates are obtained according to the reactions stated in equations ( ),( ),(3). These represent three sub-reactions from the Schrock cycle, chosen since they are deemed to be the determining factors in the overall reaction, and from here on these are referred to as scoring functions. For simplicity, the scoring functions will be referred to in a reduced form without the molybdenum prefix, for example NH 3 N 2 .