Infrared Spectra of Oxygen-Rich Yttrium and Lanthanum Dioxygen/Ozonide Complexes in Solid Argon

The reactions of yttrium and lanthanum atoms with O-2 have been reinvestigated using matrix isolation infrared spectroscopy and theoretical calculations. The ground-state yttrium and lanthanum atoms react with O-2 to produce the inserted yttrium and lanthanum dioxide molecules as the initial products. The yttrium. dioxide molecule interacts spontaneously with additional O-2 molecules to form the oxygen-rich OY(eta(2)-O-3) complex and possibly the (eta(2)-O-2)Y(eta(2)-O-3)(2) complexes upon sample annealing, which can be regarded as the side-on bonded yttrium monoxide ozonide complex and the superoxo yttrium bisozonide complex, respectively. Visible irradiation induces the isomerization of the OY(eta(2)-O-3) complex to the superoxo yttrium peroxide Y(eta(2)-O-2)(2) isomer, in which both the superoxo and peroxo ligands are side-on bonded to the yttrium center. The lanthanum dioxide molecule reacts with additional O-2 molecules to form the lanthanum dioxide-dioxygen complex with planar C-2 nu symmetry, which rearranges to the lanthanum monoxide ozonide complex, OLa(eta(2)-O-3), under near-infrared excitation.