Ra. Morgan et al., RESONANCE-ENHANCED MULTIPHOTON IONIZATION SPECTROSCOPY OF METHANETHIOL, Journal of the Chemical Society. Faraday transactions, 91(17), 1995, pp. 2715-2721
Citations number
28
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
We report the first multiphoton study of excited electronic states of
the methanethiol molecule. Members of four Rydberg series are identifi
ed via the two- and three-photon resonance enhancements they provide i
n the multiphoton ionisation spectrum of this molecule. Spectral analy
sis is aided by parallel measurements of the kinetic energies of the a
ccompanying photoelectrons. Such studies also yield a refined value fo
r the first ionisation limit of methanethiol: E(i) = 76260 +/- 40 cm(-
1). Detailed inspection of the photoelectron spectra obtained followin
g REMPI via all but the lowest energy resonances reveal the presence o
f 'slower' photoelectrons, the energies of which can be interpreted if
we invoke near-resonant inter-Rydberg state vibronic mixing. It is su
ggested that such inter-Rydberg state vibronic mixing must be rather c
ommonplace in polyatomic systems, especially in molecules like methane
thiol where symmetry imposes few restrictions on the allowed state cou
plings.