[Show abstract][Hide abstract] ABSTRACT: A study on Auger-electron spectra of F3SiCH2CH2Si(CH3)3 was performed by using monochromatized synchrotron radiation. The normal Si:L23VV Auger-electron spectrum was measured in the vapor phase and characterized through the ab initio molecular orbital calculation. The cascade Si:L23VV Auger-electron spectra were also obtained by L23-holes creation through Si:KL23L23 Auger transitions after Si:1s photoexcitation in the vapor phase or its photoelectron emission in the condensed phase. Further the C:KVV and F:KVV Auger-electron spectra were measured and discussed in comparison with those of some related molecules.
Full-text · Article · Dec 2009 · Journal of Electron Spectroscopy and Related Phenomena
[Show abstract][Hide abstract] ABSTRACT: Excitation (total ion yield) and de-excitation (resonant photoemission) spectra have been measured in the Si 1s photoexcitation region of the F3SiCH2CH2Si(CH3)3 molecule using monochromatized undulator radiation. Theoretical calculations within the framework of density functional theory have reproduced the observed total ion yield spectrum very well. The first peak at the lowest photon energy, coming from Si 1s excitation at the trimethyl side into a vacant orbital, induces spectator Auger decays in which the excited electron remains in its valence orbital. The second peak produced through excitation of Si 1s electron at the trifluoride side generates resonant Auger decays in which the excited valence electron remains predominantly also in the valence orbital or is partly shaken up into higher Rydberg orbitals. The third peak generated through Si 1s excitation at the trifluoride side produces resonant Auger decays in which the excited Rydberg electron remains or is partly shaken down to a lower lying valence molecular orbital. These findings exhibit a clear distinction between resonant Auger decays following photoexcitation of Si 1s electrons under different chemical environments.
Full-text · Article · Oct 2009 · The Journal of Chemical Physics
[Show abstract][Hide abstract] ABSTRACT: A variety of photoelectron spectra for gas phase F3SiC2H4Si(CH3)3 molecule have been measured using monochromatized undulator radiation and a hemispherical electrostatic analyzer. Valence photoelectron spectrum shows many peaks for ionization from shallow and deep molecular orbitals in the binding energy region of 9–40eV. A calculation of ionization energies using the outer valence Green's function method indicates energies in agreement with experimental results below 17.5eV. Spectra for Si L-shell electron emission show chemical shifts of Si atoms induced from different chemical environments around two Si atoms and also exhibit spin–orbit splitting for 2p photoelectrons. Further photoelectron spectra for C K-shell and F K-shell are discussed in comparison with those of related molecules.
Full-text · Article · Jun 2009 · Journal of Electron Spectroscopy and Related Phenomena