A spectroscopic study of the rhodium monoboride molecule

Abstract

A laser-induced fluorescence spectrum of rhodium monoboride (Rh10B and Rh11B) has been recorded under jet-cooled conditions between 425 and 505 nm at rotational resolution. Two electronic transitions have been identified: a 1Σ–X1Σ system with (0,0) band at 19 985 cm−1 and a 1Π–X1Σ system with (0,0) band at 20 110 cm−1. Both excited states are less strongly bound than the ground state. For the [20.0] 1Σ state of Rh10B/Rh11B, ωe ≈ 682/651 cm−1 and B 0 = 0.533/0.484 cm−1; for the [20.1]1Π state, ΔG 1/2 = 739/710 cm−1 and B 0 = 0.558/0.521 cm−1. Dispersed fluorescence experiments indicate the presence of low-lying electronic levels at 360, 9440 and 10 228 cm−1.