Studies and ab initio calculations on the characteristics of the C state of SF2

SF2 radicals were generated by a pulsed dc discharge in a gas beam of SF2 and Ar. The (2+1) resonance-enhanced multiphoton ionization (REMPI) excitation spectrum of SF2 radical was obtained between 330 and 365 nm. The SF+ cation signals were also observed in the same wavelength range. Ab initio calculations show that the C state is a predissociative state with Rydberg characteristics. The REMPI spectrum is assigned to a two-photon resonant excitation of the SF2 radical (the (BB1)-B-1 and C(1)A(1) states). Potential energy curves of excited states of the SF2 radical obtained by ab initio calculations suggest that SF+ cations originate from the ionization of SF fragments yielded from the dissociation of the C state.