Theoretical radiative data are presented for selected transitions involving the strongly bound 12Πu and 14Σ- g states of Be+ 2. The wavefunctions stem from a Multi-Reference Configuration Interaction (MRD-CI) treatment correlating three valence electrons. Absorption from 12Πu (σ2 gπu into 12Δg and 12Σ- g (both σgπ2 u) have oscillator strengths f{hook}00 of 0.028 and 0.073, respectively. The unusual stability of states having single or double excitation into the πu MO dominates the spectrum and make experimental detection of Be+ 2 feasible. An absorption f{hook}00 of 0.049 for the Rydberg transition 22Δg ← 12Πu(πu → 3dδ) also indicates a high intensity spectrum. Absorption from 14Σ- g generally leads to rupture of the BeBe bond since the upper states are either repulsive 14Πu, 14Σ- u) or metastable (34Πu).
Journal of Molecular Spectroscopy
Ottawa-Carleton Chemistry Institute

Bruna, P.J., Meng, B.Q., & Wright, J.S. (1993). Importance of Strongly Bound Excited States in the Electronic Spectrum of Be+ 2. Journal of Molecular Spectroscopy, 159(1), 79–95. doi:10.1006/jmsp.1993.1106