Control of chemical reactions by core excitations

Recent progress in synchrotron radiation techniques in a soft X-ray region has developed a new field in chemistry. Using tunable synchrotron radiation in a soft X-ray region, site selective core excitation can be achieved. Th e site-specificity of the consequent chemical reactions is one of the attra ctive issues and has been studied for various kinds of molecules. During th ese studies, a remarkable site-specific reaction has been found in the case of photon stimulated ion desorption (PSID) of polymethylmethacrylate (PMMA ) thin films. The PSID of PMMA has been examined in order to elucidate the reaction mechanism using total electron yield, total and partial ion yield, Auger electron, and Auger electron-photoion coincidence spectroscopies. In this paper we discuss the possibility of controlling chemical bond scissio n by using the site-specific photochemical surface reactions mainly based o n the recent experimental results. (C) 2001 Elsevier Science B.V. All right s reserved.