Product energy distribution heat bath

Note the large vibrational heat bath which insures that the translational and rotational product energy distributions are well described by a canonical distribution at a temperature T which is the product system temperature. 

The translational energy distribution [Eq. (9.53)] must now be corrected for the effect of the centrifugal barrier. In PST, the P(E T ) function is not that of a free particle in a heat bath. It is best to consider the distribution in terms of the flux of the reverse association reaction. By microscopic reversibility, this will be the distribution of product energies in the reaction. The flux for the reverse association reaction is given by... 

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