Observation of the 5p Rydberg states of sulfur difluoride radical by resonance-enhanced multiphoton ionization spectroscopy

摘要

Sulfur difluoride radicals in their ground state have been produced by a "laser-free" pulsed dc discharge of the SF6/Ar gas mixtures in a supersonic molecular beam and detected by mass-selective resonance-enhanced multilphoton ionization (REMPI) spectroscopy in the wavelength range of 408-420 nm. Analyses of the (3+1) REMPI excitation spectrum have enabled identification of three hitherto unknown Rydberg states of this radical. Following the Rydberg state labeling in our previous work [see J. Phys. Chem. A 102, 7233 (1998)], these we label the (K) over tilde (5p(1)) [nu(0-0)=71 837 cm(-1), omega(1)'(a(1) sym str)=915 cm(-1)], (L) over tilde (5p(2)) [nu(0-0)=72 134 cm(-1), omega(1)'(a(1) sym str) =912 cm(-1)], and (M) over tilde (5p(3)) [nu(0-0)=72 336 cm(-1), omega(1)'(a(1) sym str)=926 cm(-1)] Rydberg states, respectively. [Origins, relative to the lowest vibrational level of the (X) over tilde (1)A(1) ground state, and vibrational frequencies of the symmetric S-F stretching mode are suggested by the numbers in brackets.] Photofragmentation process of SF2+ --> SF+ +F that relates to the REMPI spectrum was discussed. (C) 2008 American Institute of Physics.