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1728477 
Journal Article 
Reaction of gaseous mercury with molecular iodine, atomic iodine, and iodine oxide radicals - Kinetics, product studies, and atmospheric implications 
Raofie, F; Snider, G; Ariya, PA 
2008 
Yes 
Canadian Journal of Chemistry
ISSN: 0008-4042
EISSN: 1480-3291 
86 
811-820 
Mercury is present in the Earth's atmosphere mainly in elemental form. The chemical transformation of mercury in the atmosphere may influence its bioaccumulation in the human food chain as well as its global cycling. We carried out the first kinetic and product studies of the reactions of gaseous mercury with molecular iodine, atomic iodine, and iodine oxide radicals at tropospheric pressure (similar to 740 Torr) and 296 +/- 2 K in air and in N(2) (1 Torr = 133.322 4 Pa; 0 degrees C = 273.15 K). Atomic iodine was formed using UV photolysis of CH(2)I(2). IO radicals were formed by the UV photolysis of CH(2)I(2) in the presence of ozone The reaction kinetics were studied using absolute rate techniques with gas chromatographic and mass spectroscopic detection (GC-MS). The measured rate coefficient for the reaction of Hg(0) with I(2) was <= (1.27 +/- 0.58) x 10(-19) cm(3) molecule(-1) s(-1). The reaction products were analyzed in the gas phase from the suspended aerosols and from deposits on the walls of the reaction chambers using six complementary methods involving chemical ionization and electron impact mass spectrometry, GC-MS, a MALDI-TOF mass spectrometer, a cold vapor atomic fluorescence spectrometer (CVAFS), and a high-resolution transmission electron microscope (HRTEM) coupled to an energy dispersive spectrometer (EDS). The major reaction products identified were HgI(2), HgO, and HgIO or HgOI. The implications of the results are discussed with regards to both the chemistry of atmospheric mercury and its potential implications in the biogeochemical cycling of mercury. 
mercury; molecular iodine; atomic iodine; iodine oxide radicals kinetics; product study; atmospheric chemistry