Negative-Ion Enhancements in Electron-Stimulated Desorption of CF2Cl2 Coadsorbed with Nonpolar and Polar Gases on Ru(0001)
نویسندگان
چکیده
Electron-stimulated desorption of F and Cl from submonolayer CF2Cl2-covered Ru(0001) is strongly affected by coadsorption of polar molecules (H2O and NH3) and nonpolar rare-gas atoms (Xe, Kr, and Ar). Giant anionic enhancements (up to 102-104) are observed for polar molecules, which are several orders of magnitude higher than by nonpolar atoms. The giant enhancements are attributed to enhanced dissociation of CF2Cl2 by attachment of self-trapped electrons in polar molecules. [S0031-9007(99)09120-6]
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تاریخ انتشار 1999