Vibrationally resolved cross sections for the photoionization of CS 2 Academic Article uri icon

abstract

  • We have performed vibrationally resolved calculations of the excitation of the symmetric stretch in the photoionization of CS2leading to the X2Πg, A2Πu, B2Σu+, and C2Σg+states of CS2+. Previous theoretical work has determined that the kπgshape resonance in the (5σu)-1channel consists mainly of a linear combination of low lying virtual d orbitals on sulfur and is thus essentially atomic in nature. This conclusion was primarily based on the shape of the resonant wave function and the insensitivity of the energy of the resonance to bond stretching. Here, we have determined that the energies of the kπ shape resonances located well above threshold and the σ bound states just below threshold are insensitive to bond length. We have also found nearly constant vibrational branching ratios in all channels and polarization components. This is in qualitative agreement with experimental vibrationally resolved cross sections [S. Kakar, H. C. Choi, and E. D. Poliakoff, J. Chem. Phys. 97, 4690 (1992)] which show nearly constant vibrational branching ratios. Our present results indicate that caution must be exercised when using bond length sensitivity as an exclusive means to determine the existence of shape resonances. © 1994 American Institute of Physics.

author list (cited authors)

  • Stratmann, R. E., & Lucchese, R. R.

citation count

  • 10

publication date

  • December 1994