Dissociative Photoionization of ClC(O)SCH2CH3 following sulfur 2p and chlorine 2p

RODRIGUEZ PIRANI, LUCAS SEBASTIÁN; ERBEN, MAURICIO FEDERICO; GERONÉS, MARIANA; ROMANO, ROSANA MARIEL; CAVASSO FILHO, REINALDO; DELLA VÉDOVA, CARLOS OMAR

Campinas, Brasil

Congreso; XIX Reuniao Anual de Usuários (RAU); 2009

Laboratório Nacional de Luz Síncrotron

Thioesters of the type XC(O)SY occur naturally in a variety of environments.In vivo, thioesters result from the association of a methanethiol moiety and acylCoA via spontaneous or enzymatically promoted reactions. This, allied to thebiochemical importance of coenzyme A and its acyl derivatives, has ensured themaintenance of a lively interest in thioesters. We have started recently a generalproject aimed at elucidating the shallow and innershell core electronic propertiesof thioesters, and hence gaining a fuller understanding of the photodissociationchannels open to these compounds. Thus, photoionization studies have been car-ried out on species such as FC(O)SCl, ClC(O)SCl thioacetic acid andCH3OC(O)SCl using synchrotron radiation in the range 1001000 eV. Follow-ing these studies, we became interested in other simple thioester compound. Herewe report a study of the photon impact excitation and dissociation dynamics ofClC(O)SCH2CH3 exited at the S 2p and Cl 2p levels by using synchrotron radia-tion. The TIY spectra of ClC(O)SCH2CH3 following S 2p excitations is dominatedby a group of four signals centered at 164.6, 165.9, 167.2 and 168.4 eV, while theionization edge is located at approximately 170.9 eV. In the Cl 2p region onlyone signal can be observed at 201.0 eV. PEPICO and PEPIPICO spectra for thismolecule were recorded on each resonance, and also below and above resonancebands. Possible fragmentations mechanisms are deduced from the interpretation ofthe PEPIPICO spectra.