A new source for vibrationally excited and rotationally cold metal-oxide molecules: spectroscopic characterization of the low-lying a 3Π2 metastable excited state of the MgO molecule

Several ν=0–4 series of hot bands in the 36 000–39 000 cm−1 spectral region have been recorded from the MgO(a 3Π2) metastable state (produced by the products of laser vaporization of a magnesium rod reacting with N2O) to higher-lying MgO(3Π2) vibronic levels, and have been rotationally resolved. From the analysis of the spectra, rotational and vibrational spectroscopic constants for this interesting low-lying MgO(a 3Π2) excited state, which formally has Mg+O− ‘open-shell’ character, have been determined.