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# Fragmentation of the valence electronic states of PSCl3+ studied by threshold photoelectron–photoion coincidence spectroscopy

Howle, C. R. and Chim, R. Y. L. and Tuckett, R. P. and Malins, A. E. R. (2004) Fragmentation of the valence electronic states of PSCl3+ studied by threshold photoelectron–photoion coincidence spectroscopy. Chemical Physics, 303 (1-2). pp. 227-234. ISSN 0301-0104

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URL of Published Version: http://dx.doi.org/10.1016/j.chemphys.2004.03.032

Identification Number/DOI: doi:10.1016/j.chemphys.2004.03.032

The threshold photoelectron spectrum and threshold photoelectron photoion coincidence spectrum of PSCl$$_3$$ are reported in the range 9.5-22.5 eV. Tunable ionising radiation with a resolution of 0.3 nm is provided from a synchrotron source coupled to a vacuum-UV monochromator. The coincidence spectra are recorded continuously as a function of photon energy, allowing yields of the fragment ions to be obtained. The ground state of PSCl$$_3^+$$ is bound with respect to dissociation, whereas the five lowest excited electronic states dissociate by P-Cl bond cleavage to PSCl$$_2^+$$. An upper limit of 629 ± 30 kJ mol$$^{-1}$$ is determined for the enthalpy of formation of PSCl$$_2^+$$ at 298K. For energies above ca. 15 eV, fragment ions corresponding to multiple bond cleavages are observed; PSCl$$^+$$ and PCl$$_2^+$$, PS$$^+$$ and PCl$$^+$$. Because of uncertainties in thermochemistry, it is possible only for PS$$^+$$ to determine the neutrals that form with this fragment cation. Translational kinetic energy releases have been measured into PSCl$$_2^+$$ + Cl at the energies of the Franck-Condon maxima of the valence states of PSCl$$_3^+$$, and the results compared with models assuming statistical and impulsive dissociation. The kinetic energy data suggest that the six lowest excited states of PSCl$$_3^+$$ decay by a mechanism intermediate between statistical dissociation from the ground state of PSCl$$_3^+$$ following rapid internal conversion and impulsive dissociation from the initially-excited electronic state.

Type of Work: Article 2004 (Publication) Schools (1998 to 2008) > School of Chemical Sciences School of Chemistry TPEPICO ; threshold photoelectrum spectrum ; thiophosphoryl chloride ; PSCl3 QD Chemistry University of Birmingham Elsevier B.V. 754 YES

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