Laser-induced fluorescence spectroscopy of the B̃–X̃ and ÖX̃ transitions of CaNH2

Abstract

Laser‐induced fluorescence spectra of the B̃ 2 B 1–X̃ 2 A 1 and à 2 B 2–X̃ 2 A 1 transitions of the CaNH2 radical, produced in a pulsed supersonic expansion, have been recorded. The ΔK a = ±1 rotational subbands showed an intensity alternation revealing the molecule to be planar or quasiplanar. The excited à and B̃ states exhibit unusually large spin splittings which are shown to arise from the coupling between the electronic orbital motion and the a‐axis nuclear rotation. This interaction has been successfully modeled in terms of a‐axis rotation–orbital and spin–orbital interactions of an electron localized in a pπ orbital on the calcium atom.