njit-etd2003-111 - New Jersey Institute of Technology

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literature and from trends in homologous series of reactions. Activation energies come
from DFT plus evaluated endothermicity of reaction AU,„, from analysis of Evans-
Polanyi relationships for abstractions plus evaluation of ring strain energy, and from
analogy to similar reactions with known energies. Thermochemical properties are
provided for each system.
Reduced sets of three vibration frequencies and their associated degeneracies are
computed from fits to heat capacity data, as described by Ritter and Bozzelli et al. 37,38
These have been shown by Ritter to accurately reproduce molecular heat capacities,
CAST), and by Bozzelli et a1. 38 to yield accurate ratios of density of states to partition
coefficient, p(E)IQ.
Lennard-Jones parameters, sigma (angstroms) and Elko (Kelvin's), are obtained
from compressibility. 4o tabulations 39 and from a calculation method based on molar volumes and
When necessary, estimation is done in a consistent and uniform manner via use of
generic reaction rate constants with reference to literature, experiment or theoretical
calculation in each case. The QRRK calculation input parameters and their references are
listed in the table associated with the respective reaction system.
2.3.6.2 Quantum RRK /Master Equation Calculation. The quantum RRK (QRRK)
lmaster equation analysis is described by Chang et al. 31'41 The QRRK code utilizes a
reduced set of three vibration frequencies which accurately reproduce the molecule's
(adduct) heat capacity; the code includes contribution from one external rotation in
calculation of the ratio of the density of states to the partition coefficient p(E)lQ.