Formation of XeI(B) in low pressure inductive radio frequency electric discharges sustained in mixtures of Xe and I2

Low pressure excimer discharges ~,1–5 Torr! are of interest for use as ultraviolet sources for lighting applications. XeI(B) is an attractive candidate for excimer lamps due to the low corrosive properties of iodine. The excimer is thought to be formed by either harpoon or ion-ion recombination reactions, the latter of which requires a third body. The formation of the excimer at low pressures is therefore problematic. To address this issue, an investigation was conducted to determine the kinetic processes which produce XeI(B) in a low pressure ~0.5–5 Torr! inductive radio frequency discharge sustained in Xe and I2 . The diagnostics applied in this study include laser-induced fluorescence, optical absorption spectroscopy, and optical emission spectroscopy. Our results indicate that for the experimental conditions, Xe1I2**→XeI~B)1I is a major reaction producing the excimer. This result differs from studies performed at higher pressures which concluded that the harpoon reaction between Xe* and I2 or ionic recombination between Xe2 1 and I are the major sources of XeI(B). © 1996 American Institute of Physics. @S0021-8979~96!03222-7#