A BOND LENGTH REACTION COORDINATE FOR UNIMOLECULAR REACTIONS .2. MICROCANONICAL AND CANONICAL IMPLEMENTATIONS WITH APPLICATION TO THE DISSOCIATION OF NCNO

A method is described for implementing Rice-Ramsberger-Kassel-Marcus theory with the reaction coordinate chosen to be the bond length of the breaking bond. A consideration of both microcanonical and canonical calculations is given. The method described is similar to a previously described implementation in which the reaction coordinate was, instead, chosen to be the distance separating the centers of mass of the two dissociating fragments. This bond length based implementation is applied to the calculation of energy and angular momentum resolved rate constants and product vibrational distributions for the dissociation of NCNO. A comparison of the results of these calculations with the corresponding center-of-mass separation distance based results demonstrates that the bond length provides a considerably improved description of the reaction coordinate in the region of the inner transition state.