Sulfur difluoride radicals in their ground state have been produced by a "laser-free" pulsed dc discharge of the SF$_{ 6}$/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(5p$_{ 1}$) [$nu_{ 0-0}$ = 71 837 cm$^{ -1}$, $omega_{ 1}^{ '}$(a$_{ 1}$ sym str) = 915 cm$^{ -1}$], L(5p$_{ 2}$) [$nu_{ 0-0}$ = 72 134 cm$^{ -1}$, $omega_{ 1}^{ '}$(a$_{ 1}$ sym str) = 912 cm$^{ -1}$], and M(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$^{ 1}$A$_{ 1}$ ground state, and vibrational frequencies of the symmetric S-F stretching mode are suggested by the numbers in brackets.] Photofragmentation process of SF$_{ 2}$$^{ +}$--SF$^{ +}$ + F that relates to the REMPI spectrum was discussed.
Categories: physics.chem-ph