COLL 284 |
| Aqueous systems as proxies for atmospheric aerosols were studied by probing the structure and chemistry at the air-aqueous interface using vibrational sum frequency spectroscopy. Adsorption of methanol and methyl chloride on the water surface was probed. We find that although methyl chloride adsorbs and is taken up readily by the water surface, orientation is random, possibly affecting atmospheric chemical reaction pathways. Methanol, as also shown for other terminal alcohols, is anchored via hydrogen bonding to the liquid water and the CH3 moiety populates the water surface in a well ordered manner. Alcohol organization is very different relative to the alkyl chlorides and bromides, methyl and butyl species. Additionally, the surface structure of salt solutions with mono and divalent cations was probed. Interesting behavior of interfacial nitrate was observed. Moreover, magnesium shows unique behavior relative to other cations. |
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The Physical Chemistry of Environmental Interfaces
9:00 AM-1:10 PM, Tuesday, April 8, 2008 Morial Convention Center -- Rm. 225, Oral
Division of Colloid & Surface Chemistry |