Matrix reactions of molecular oxygen and ozone with aluminum atoms

Frozen matrices of nitrogen or Ar containing small concentrations of Al atoms and O sub 2 or O sub 3 have been prepared by matrix isolation techniques and studied by infrared absorption spectroscopy. The spectra were analyzed on the basis of isotopic oxygen substitution, variations in the concentrations of reagents and changes in band intensities after reagent diffusion and reaction in the matrix. These analyses have shown that the principal reaction product in N matrices with either O sub 2 or O sub 3 was an asymmetrical and highly bent aluminum dioxygen molecule, AlOO (C sub s ). Very little of this species was produced in Ar matrices. The stretching modes of AlOO in N were identified as 1337 cm exp 1 for v sub 1 (O--O) and 1091 cm exp 1 for v sub 3 (Al--O). Metal ozonides absorbing in the region of 850 cm exp 1 also were produced by both O reagents in both N and Ar matrices. Several other complex species were identified as additional reaction products. No bands could be identified as belonging to a metal superoxide species, which is the principal product in the matrix reactions of Ga, indium and Tl with O sub 2 . 24 ref.--AA