title: Dissociation dynamics of positive-ion and negative-ion fragments of gaseous and condensed Si(CH(3))(2)Cl(2) via Si 2p, Cl 2p, and Cl 1s core-level excitations.
abstract: The state-selective positive-ion and negative-ion dissociation pathways of gaseous and condensed Si(CH(3))(2)Cl(2) following Cl 2p, Cl 1s, and Si 2p core-level excitations have been characterized. The excitations to a specific antibonding state (15a(1) (*) state) of gaseous Si(CH(3))(2)Cl(2) at the Cl 2p, Cl 1s, and Si 2p edges produce significant enhancement of fragment ions. This ion enhancement at specific core-excited states correlates closely with the ion kinetic energy distribution. The results deduced from ion kinetic energy distribution are consistent with results of quantum-chemical calculations on Si(CH(3))(2)Cl(2) using the ADF package. The Cl(-) desorption yields for Si(CH(3))(2)Cl(2)Si(100) at approximately 90 K 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 insight into the state-selective ionic fragmentation of molecules via core-level excitation.
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan, Republic of China. jmchen@nsrrc.org.tw
authors.forename: J M
authors.initials: JM
authors.lastname: Chen
authors.forename: K T
authors.initials: KT
authors.lastname: Lu
authors.forename: J M
authors.initials: JM
authors.lastname: Lee
authors.forename: C K
authors.initials: CK
authors.lastname: Chen
authors.forename: S C
authors.initials: SC
authors.lastname: Haw
mesh_terms: D002713:Chlorine / Q000737:chemistry*; D005740:Gases / Q000737:chemistry*; D007477:Ions; D007700:Kinetics; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D011522:Protons; D012825:Silicon / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D005740:Gases; D007477:Ions; D009942:Organometallic Compounds; D011522:Protons; D002713:Chlorine; D012825:Silicon