Dissociative Photoionization of sulfenylcarbonyl -C(O)S- compounds induced by synchrotron radiation

MARIANA GERONÉS; MAURICIO F. ERBEN; EMILIANO CORTÉS; LUCAS RODRÍGUEZ PIRANI; MAOFA GE; ROSANA M. ROMANO; LI YAO; CARLOS O. DELLA VÉDOVA

REVISTA MEXICANA DE FíSICA

SOC MEXICANA FISICA

Año: 2010 vol. 56 p. 24 - 29

0035-001X

The TIY spectra of shallow-core levels and inner-shell level of carbonylsulfenyl (XC(O)SY) compounds were obtained in the range 100-1000 eV by using synchrotron radiation and coincidence detection techniques. Complex electronic processes occur at resonant energies below the S 2p ionization edge, which appear to be characteristic for -SC(O)- containing compounds. The observed features in the TIY spectra could be related with several phenomena such as electronic transitions to vacant orbitals with contributions of spin-orbit splitting of the S 2p terms of the ionized species, autoinization of transitions to Rydberg levels or a contribution of both of them. Thus, this family of compounds deserves further studies involving the use of electron spectroscopy based methods to cover these aspects. Time-of-flight PEPICO and PEPIPICO multicoincidence techniques were applied around the different transition edges. In the case of FC(O)SCl and ClC(O)SCl, it is expected that valence holes created in the Auger decay may delocalize over the whole planar molecules. In consonance with this fact, the fragmentation patterns are practically independent upon the atomic site of the core hole and non-specific fragmentation should be expected. When the size of the molecule increases, as in the related sulfenylcarbonyl species CH3C(O)SH and CH3OC(O)SCl, different fragmentation patterns were obtained as the incident photon energy was varied. The dissociation dynamic for the main ion-pair production has also been discussed. Dissociation channels were studied by evaluating the shape and slope of selected coincidence islands in the PEPIPICO spectra. Two- , three- and four-body processes, were proposed.