Clusters Formed Directly from Laser Ablation of Ytterbium Oxide: Yb3O4+ and Yb6O8+

Abstract

Excimer laser ([lambda] = 308 nm) ablation of solid Yb[sub 2]O[sub 3] into vacuum has been found to generate polyatomic ytterbium oxide ions: Yb[sub 2][sup +], Yb[sub 2]O[sup +], Yb[sub 2]O[sub 2][sup +], Yb[sub 3]O[sub 4][sup +], Yb[sub 3]O[sub 4][sup +], and Yb[sub 6]O[sub 8][sup +]. In contrast, other Ln[sub 2]O[sub 3] (Ln = Sm, Eu, Gd, Dy) formed observable amounts of only the atomic and/or monoxide ions, Ln[sup +] and LnO[sup +]. The stoichiometry of Yb[sub 6]O[sub 8][sup +] suggests mixed-valence Yb[sup II/III] content. The vapor composition found for vacuum ablation of Yb[sub 2]O[sub 3] differs notably from both that reported for equilibrium vaporization of Yb[sub 2]O[sub 3] and that for reactive (with O[sub 2]) condensation of ablated ytterbium metal. 20 refs., 6 figs., 2 tabs.