HR: 12:05h
AN: P32B-04 INVITED    [Abstracts]
TI: The formation and fate of oxidants on icy satellite surfaces
AU: * Orlando, T M
EM: thomas.orlando@chemistry.gatech.edu
AF: School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Dr., Atlanta, GA 30332, United States
AU: Grieves, G A
EM: gregory.grieves@chemistry.gatech.edu
AF: School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Dr., Atlanta, GA 30332, United States
AB: It is well known that the bombardment of ice covered surfaces in the outer solar system leads to chemical transformations and alteration of molecular compositions. Among the major radiolysis products remaining trapped within the ice are highly reactive, oxygen rich molecules and radicals. Studies of pure ices have revealed much information about production and survival of oxidants, but real systems are full of impurities and the ability of these oxidizers to react and alter other embedded impurities gives rise to significant indirect channels for radiation-induced chemistry. Observational and experimental evidence indicates that the presence of CO₂ is correlated with carbonaceous surfaces rather than strictly the presence of carbon bearing molecules. Graphitic substrate interactions with ice overlayers impede oxidant formation by scavenging of reactively scattered O, O⁺, OH and other fast, hot fragments. These interfacial reactions consume graphitic and carbonaceous particles and produce formic acid, formaldehyde, CO and CO₂. This talk will focus on the role of ice: grain interfacial reactions in determining the potential oxidant inventory.
DE: 5421 Interactions with particles and fields
DE: 5422 Ices
DE: 5470 Surface materials and properties
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting