Two-dimensional sub-nano mapping of surface photochemistry

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We have investigated mainly the following subject on photo-and thermo chemistry of one dimensional surface compound of AgO on Ag(110) by scanning tunneling microscope and the other surface science techniques. Here is a summary of main results :1.Reaction sites of photo-induced oxygen elimination reaction of AgO on Ag(110).We clarified the reaction sited of uv-light induced-photoelimination reaction of oxygen from AgO chains on a Ag(110) surface. The reaction is initiated with electronic excitation of AgO chains and CO formation takes place at the site where carbidic carbon exists. On this surface, AgO chains are fragmented by the photo-elimination of oxygen at the sites.2.Effect of carbidic carbon on the structure of AgO chains :Carbidic carbon pins AgO chains so that the chains do not show any structural fluctuations and the pairing of chains is observed at the low coverage. On the other hand, chains spread on a clean surface at the low coverage and shows extensive structural fluctuations.3.Reaction sites of thermal oxygen elimination and correlation between structural fluctuation and reactivity :We found that thermal oxygen elimination takes place at the ends of chains at low temperature where the one-dimensional structure of chains is hold. However, at room temperature, the reaction is enhanced when one-dimensional chains start fluctuating. This indicates that the structural fluctuation creates kinks in the chain, and oxygen atoms at the kinks are eliminated. Thus, the reaction sites are created dynamically.