On the Use of Exact Vibrational State Counting Methods in RRKM Rate Calculations.

摘要

The use of direct counts of molecular energy level degeneracies, p(E), at internal energy, E, in RRKM unimolecular reaction rate calculations is clarified. Highly accurate densities of states for use in practical rate calculations can be obtained by utilizing an energy level grain size of 1-5/cm and by suitable averaging of P(E) over small energy intervals. An easily programmed algorithm for rounding energy levels to multiples of this grain size is given and applied to sum and density calculations. (Author)