Vacuum UV fluorescence excitation spectroscopy of BCl₃in the range 35–140 nm

Abstract

Fluorescence excitation spectra of BC13 have been recorded in the range 35-140 nm (9-35 eV) using synchrotron radiation. Both resonant and non-resonant peaks are observed corresponding to neutral fragment (i.e. BC12) and parent ion (i.e. BC1 +) emission. BC12 emission results from dissociation of low-lying Rydberg states of BC13 in the energy range 9-12 eV, and at least two electronic transitions in BC12 are observed. One (in the range 400-650 nm) originates from dissociation of the 3s and 3p Rydberg states, whilst the other (in the range 250-500 nm) originates from higher members of the s, p and d Rydberg series. The emitting states in BC1 + are the I3 2E' and 1~ 2A] states with adiabatic ionization potentials of 15'3 and 17"7eV. The results are compared with vacuum UV absorption studies of BCI3, and with similar experiments on BF 3 which lead to fluorescence processes in BF 2 and BF~-.

Vacuum ultraviolet fluorescence excitation spectroscopy of BBr3in the range 8–20 eV

“…The close similarity between the photoabsorption and fluorescence excitation spectra suggests that dissociation to form excited emitting states of the BBr~ radical is a major decay pathway for these BBr 3 Rydberg states. The spectra are considerably more complicated than the equivalent fluorescence excitation spectra of either BF 3 or BCI a [1][2][3]. Planckaert et al attribute much of the additional structure to transitions to triplet Rydberg states which become weakly allowed because of the relatively large spin-orbit coupling interaction due to the bromine atoms.…”

“…The experiments described form part of a series of studies of the fluorescence excitation spectroscopy of the group III halides [1][2][3]. The boron trihalides, BF3, BCI~ and BBr3, are widely used in the radiofrequency plasma etching of semiconductor devices [4].…”

“…The vacuum ultraviolet spectroscopy of the boron trihalides has been investigated by several groups using a number of different experimental techniques [1][2][3][5][6][7]. X*A~ 0"00 Calculated using 0 K heats of formation [22].…”

Matrix isolation study of the interaction of excited neon atoms with BCl3: Infrared spectra of BCl+3, BCl+2, and BCl−3

“…The photoelectron spectroscopic studies of Bassett and Lloyd 3 are consistent with the photoionization observations. Tuckett and coworkers studied the fluorescence excitation spectroscopy 4,5 and fragmentation pattern 6 of BCl 3 . They found that when BCl 3 is excited in the 9-12 eV energy range the fluorescence is dominated by BCl 2 .…”

Electron Interactions With BCl3

“…29 A number of experimental studies contribute to an understanding of the molecular and electronic structure of the BCl 3 molecule. These include electron-impact excitation and ionization, [31][32][33] negative-ion formation, [31][32][33][34][35][36][37] electron-impact dissociation into excited fragments, [38][39][40] photoelectron spectra, 28,41,42 photoionization and photodissociation, [43][44][45][46][47][48][49] and photoabsorption and fluorescence measurements in the ultraviolet/visible ͑UV/VIS͒ region. 44 -52 Some of the photophysical studies incorporated mass analysis and fluorescence measurements and established the fragmentation patterns of BCl 3 at specific photon wavelengths ͑see Sec.…”