ABSTRACT

In recent years, the role of chlorinated organic pollutants in the environment has received increasing attention in both the scientific community and among the general public. This interest has inspired a considerable number of on-going studies directed towards the reductive dechlorination of aliphatic and aromatic pollutants such as carbon tetrachloride and polychlorinated biphenyls (PCBs). In spite of these efforts, the complete thermodynamic data for compounds such as PCBs is largely unavailable. It is through the collection of this data that we can enhance our understanding of the thermodynamics and kinetic feasibility of these reductions. In this work, computational chemistry calculations using the TITAN computer program employing the B3LYP/6-31G* method are used for the purpose of potentially filling these gaps in our information. Derived parameters include dihedral twist angles, free energies, and lowest unoccupied molecular orbital (LUMO) energies. These parameters are then related to the published results of classical thermodynamic calculations with the eventual objective of correlating thermodynamic descriptors to rate constants for reactions of PCBs with various reductants.