Matrix isolation study of the interaction of excited neon atoms with BF3: Infrared spectra of BF2, BF+2, BF+3, and BF−3

Abstract

When a Ne:BF3 sample is codeposited at approximately 5 K with a beam of neon atoms that have been excited in a microwave discharge, the infrared spectrum of the resulting solid deposit shows prominent absorptions of BF2. All three vibrational fundamentals and the ν1+ν3 combination band of BF2 isolated in solid neon are identified, and a normal coordinate analysis is conducted. In addition, infrared absorptions of the BF+3, BF+2, and BF−3 molecular ions are assigned, and the processes which occur when the solid deposit is exposed to visible and ultraviolet radiation are considered.

Ground and excited states of BF3+. Coupled cluster and density functional studies

“…Jacox and Thompson [8] observed for 11 BF 3 + vibrational frequencies of 509.6 cm À1 (out-ofplane) and 1790.8 cm À1 (BF 3 stretch), and noted that the unusually high frequency for the BF 3 + stretching fundamental is consistent with a strong PJT interaction of the 1 2 A 2 0 ground state with 2 E 0 excited states. An absorption at 1661.6 cm À1 , initially assigned to 11 BF 3 + [9], was later reassigned to BF 2 OH + . However, so far there is no direct experimental confirmation of a C 2v state.…”

The infrared spectra of BF3+ and BF2OH+ trapped in solid neon

“…The observations on BF 2 and BF 2 + and the assignments for these products in the present study are similar to those previously reported. 1 Moderately intense to strong, structured absorptions appeared near 500, 2080, and 2150 cm −1 in all of the discharge experiments. These are readily assigned to F 11 BO and F 10 BO, previously identified in the neon-matrix experiments of Snelson.…”

“…Figure 4, for the 3230 to 3260 cm −1 spectral region, shows two new, weak to moderately intense absorptions which had been above the noise level in only one of the earlier experiments. 1 The photodestruction behavior of several prominent product absorptions falls into two categories:…”

“…1 Assignments were obtained for infrared absorptions of BF 3 + , BF 2 , BF 2 + , and BF 3 − , each of which had a distinctive photodestruction behavior when the initial deposit was exposed to filtered radiation in the visible and near ultraviolet spectral region.…”

“…1,5 First, since FBO was present and BF 2 OH was later found to be an important species in the Ne:BF 3 experiments and since both uncharged and ionic oxygen-containing species were later identified in studies of ions derived from other inorganic fluorides, possibly oxygen-containing ions also contributed to the spectrum of Ne:BF 3 samples codeposited with discharged neon atoms. The assignment of infrared absorptions at both 1661.6 and 1790.4 cm −1 to BF 3 + also encounters some difficulty.…”