The Molecules AlO_2,Al(O_2)_2,and Al(O_2)_3:Experimental and Quantum-Chemical Investigations on the Oxidation of Aluminum Atoms

摘要

We have already mentioned the significance of peroxo- and hyperoxo complexes with unusual spin states as intermediates in oxidation processes in biology and synthetic chemistry when we reported the oxidation of A1X molecules with O2 under matrix-isolation conditions.'1"2' The reactions of metal atoms with oxygen discussed herein also prove to be complex,since electrons are taken up stepwise by the O2 molecules with retention of symmetry and spin rules (O2^O2 ^O22~).On the preparative scale,this process results exclusively cleavage of the O~O bond and the formation of O2~ ionswith metal cations these ions form particularly stable oxides,such as A12O3.To investigate the primary steps of this reaction we have treated aluminum atoms with an increasing excess of O2 in the matrix-gas argon under matrix-isolation conditions and have obtained the molecules A1O2 (1),A1(O2)2 (2),and A1(O2)3 (3).These result are reported herein,while details of the spectra and the results of quantum-chemical calculations are given in the Supporting Information.