Enhanced production of ionic photofragments of Si(CH_3)_2Cl_2 following core-to-valence excitation

摘要

The state-selective positive-ion and negative-ion dissociation pathways for gaseous and condensed Si(CH_3)_2Cl_2 following the Cl 2p and Si 2p core-level excitations have been characterized using synchrotron radiation. The Si 2p → 15a_1~* excitation of Si(CH_3)_2Cl_2 induces an enhancement of the Cl~(+) desorption yield in the condensed phase and the Si(CH_3)_2~+ and SiCH_3~+ yields in the gaseous-phase. The Crdesorption yields are notably enhanced at the 15a_1~* resonance at both Cl 2p and Si 2p edges. The resonant enhancement of Cl~- yield occurs through the formation of highly excited states of the adsorbed molecules. These results provide an insight into the comprehensive understanding of the state-selective fragmentation of molecules via core-level excitation.