HgBr2 (+M) = HgBr + Br (1)
HgBr (+M) = Hg + Br (2)
Hg + Br2 = HgBr + Br (3)
HgBr + Br2 = HgBr2 + Br (4)
HgBrCl (+M) = HgBr + Cl (+M) (5)
HgBrCl (+M) = HgCl + Br (+M) (6)
Transition state theory was employed for the calculation of rate constants for all bimolecular reactions. Reactions 1, 2, 5, and 6 are unimolecular reactions, in which "M" is a collision partner, such as an inert gas bath, e.g. nitrogen or argon. RRKM theory was employed for the rate constant prediction of this reaction. Activation energies were calculated through the development of ab initio-based potential energy surfaces at the B3LYP level of theory with relativistic effective core potentials used for mercury. All electronic calculations were carried out using the Gaussian03 software. This data will be used to create a more complete kinetic model for mercury speciation in both coal combustion and coal gasification environments.