BrHgO + CH and BrHgO + HCHO in Atmospheric Oxidation of Mercury: Determining Rate Constants of Reactions with Prereactive Complexes and Bifurcation.

Models suggest BrHgONO to be the major Hg(II) species formed in the global oxidation of Hg(0), and BrHgONO undergoes rapid photolysis to produce the thermally stable radical BrHgO. We previously used quantum chemistry to demonstrate that BrHgO can, like OH radicals, readily abstract hydrogen atoms from sp-hybridized carbon atoms as well as add to NO and NO. In the present work, we reveal that BrHgO can also add to CH to form BrHgOCHCH, although this addition appears to proceed with a lower rate constant than the analogous addition of OH to CH.

Computational Study on the Photolysis of BrHgONO and the Reactions of BrHgO with CH, CH, NO, and NO: Implications for Formation of Hg(II) Compounds in the Atmosphere.

Global models suggest BrHgONO to be the major Hg(II) species initially formed in atmospheric oxidation of Hg(0) in most of the atmosphere, but its atmospheric fate has not been previously investigated. In the present work, we use quantum chemistry to predict that BrHgONO photolysis produces the thermally stable radical BrHgO. Subsequently, BrHgO may react with NO to form thermally stable BrHgONO, or with NO to re-form BrHgONO.