Rate Constant Computation on Some Chlorination Reactions of Hg in Combustion Flue Gas

The geometry optimizations of reactants, products and transition states were made by the quantum chemistry MP2 method at the SDD basis function level for Hg, and 6-311++G(3df, 3pd) for others. The properties of stable minimums were validated by vibration frequencies analysis. Furthermore, the microcosmic chemical reaction mechanisms of reactions were investigated by ab initio calculations of quantum chemistry. Among these chlorination reactions involving mercury, the processes of reaction Hg+Cl2 → HgCl+Cl and reaction Hg+HOCl→HgCl+OH are Hg+Cl2 →M(HgClCl) →TS(HgClCl) → HgCl+Cl and Hg+HOCl→M(HgClOH)→TS(HgClOH)→HgCl+OH, which include intermediates (M) that others do not have. On the basis of the geometry optimization, reaction rate constants within 200- 2000K are calculated neither from experimental data nor by estimated, but directly from Quantum Chemistry software-Khimera.