Reactions of Laser-Ablated Scandium Atoms with Dioxygen. Infrared Spectra of ScO, OScO, (O2)ScO, (ScO)2, and Sc(O2)2 in Solid Argon

Laser-ablated Sc atoms react with O 2 during condensation in excess argon to give ScO, OScO, and (O 2 )ScO as major products, which are identified from oxygen isotopic substitution on their matrix infrared spectra. The linear suboxide molecule ScOSc is a minor product. Annealing allows further association to form ScO 3, (ScO) 2, and Sc(O 2 ) 2 . The OScO molecule is bent: based on the oxygen-18 shift in the ν 3 mode, the valence angle is 128 ± 4°. The ν 3 fundamental of OScO at 722 cm -1 is substantially lower than the ScO fundamental at 976 cm -1, which is in accord with weaker bonds in the dioxide. Similar reactions in excess nitrogen give evidence of extensive ligation.