The visible spectrum of rhodium monoxide: RhO and RhO

Spectroscopic observations are reported for rhodium monoxide from hollow-cathode emission and laser-induced fluorescence experiments. Eleven bands of Rh¹⁶O and 10 of Rh¹⁸O, from the [15.8]²Π-X⁴Σ⁻ (b) and [16.0]²Π-X⁴Σ⁻ (b) transitions, have been rotationally analyzed. The ground state constants have been determined as B₀ = 0.4132, λ₀ = −0.58 and γ₀ = −0.102, in cm⁻¹. Rotational and lambda doubling parameters in v = 0, 1, 2, and 3 excited state vibrational levels have also been determined.