Analysis of the 3Φ → 3Δ, 1Δ → 1Π, and 1Σ → 1Π systems of lanthanum hydride, LaH and LaD

Abstract

Three new electronic band systems, assigned to LaH, have been observed both in emission (by means of a composite wall hollow cathode) and absorption (in a King furnace). The similar systems of LaD have been observed in emission. They appear between 5300 and 6500 Å. Rotational analyses of the bands have made it possible to identify the corresponding transitions as 3Φ → 3Δ, 1Δ → 1Π, and 1Σ → 1Π The singlet transitions have a common lower 1Π state. A rotational analysis of the (0, 0) and (1, 1) bands of the 3Φ4,3 → 3Δ3,2 sub-systems and of the (0, 0) band of singlet systems (with the exception of the 1Σ → 1Π system of LaD) is presented in this paper.