Laser-Assisted gas-phase reactivity of trimethylaluminum with NH_3 constrained gas pulse nozzle expansions

摘要

The results of laser-assisted (193 nm) reactivity in constrained gas pulse expansions of trimethylaluminum (TMAl) with ammonia (NH_3) are reported. During TMAl expansion with NH_3, the Lewis-acid/base adduct parent ion signal (CH_3)_3Al:NH_3~+ is observed in the gas phase by quadrupole mass spectroscopy. Laser irradiation of TMAl/NH_3 gas mixtures with 193-nm photons results in photolysis reactions of the precursor and adduct molecules. The formation of higher mass (CH_3)_kAl_l(NH_2)_m(NH)_n clusters with Al-N bonded nuclei is also observed. The cluster formation effect depends strongly on the laser energy and the pressures of the gas pulse precursors. a comparison of aluminum and gallium metalorganic species reveals a similarity in intermolecular association propensities.