Enhanced production of ionic photofragments of Si(CH3)2Cl2 following core-to-valence excitation

The state-selective positive-ion and negative-ion dissociation pathways for gaseous and condensed Si(CH3)2Cl2 following the Cl 2p and Si 2p core-level excitations have been characterized using synchrotron radiation. The Si 2 p → 15 a 1 ∗ excitation of Si(CH3)2Cl2 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 Cl−desorption yields are notably enhanced at the 15 a 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.