First infrared spectroscopic characterization of digermyl (Ge2H5) and d5-digermyl (Ge2D5) radicals in low temperature germane matrices

First Infrared Spectroscopic Detection of the Monobridged Diboranyl Radical (B2H5, C2v) and Its D5-Isotopomer in Low-Temperature Diborane Ices

With the use of a surface-scattering machine, layers of 27+/-4 nm diborane (B2H6) frosts were irradiated at 10 K and 10(-10) Torr with energetic electrons. The electrons induce a unimolecular decomposition of the diborane molecules and lead to boron-hydrogen bond rupture processes. Here, we report the first infrared spectroscopic detection of the monobridged diboranyl radical (B2H5, C2v) via the nu8 mode at 1033 cm(-1). The infrared assignment of the B2H5 isomer was verified by conducting experiments with diborane-d6 (B2D6). Under identical experimental conditions, the monobridged B2D5 isomer was observed via the nu6(1154 cm(-1)), nu8(823 cm(-1)), and nu5(1307 cm(-1)) absorptions. These data can be utilized in future spectroscopic studies of chemical vapor deposition processes to allow an identification of the monobridged diboranyl isomer in real time via infrared spectroscopy.

Mechanistic Studies on the Formation of Trifluoromethyl Sulfur Pentafluoride, SF5CF3a Greenhouse Gas

The formation of SF5CF3(X1A'), through the radical-radical recombination of SF5(X2A1) and CF3(X2A1), was observed for the first time in low-temperature sulfur hexafluoride-carbon tetrafluoride matrices at 12 K via infrared spectroscopy upon irradiation of the ices with energetic electrons. The nu1 fundamentals of the SF5(X2A1) and CF3(X2A1) radicals were monitored at 857 and 1110 cm-1, respectively; the newly formed trifluoromethyl sulfur pentafluoride molecule, SF5CF3(X1A'), was detected via its absorptions at 846 and 1160 cm-1. This formation mechanism suggests that a source for this potentially dangerous greenhouse gas might be the recombination of SF5(X2A1) and CF3(X2A1) radicals on aerosol particles in the terrestrial atmosphere.