Laser fluorescence study of MgO formed from Mg(3s3p 3P)+O2 and N2O under single-collision conditions

The reactions of metastable Mg(3s3p 3P0) atoms with O2 and N2O have been investigated under single-collision conditions by the laser-fluorescence technique. The MgO reaction product has been detected in the ground X 1Σ+ and low-lying a 3Π and A′ 1Π electronic states. The relative populations in the first six vibrational levels of X 1Σ+ and a rotational temperature characterizing the rotational distribution in v = 0 have been determined from B–X excitation spectra. The relative rates of formation for the X 1Σ+, a 3Π, and A 1Π states have been obtained from comparison of integrated fluorescence intensities in the B–X, d–a, and D–A band systems. For both reactions, little of the reaction exoergicity is channeled into MgO electronic or vibration-rotation energy. The dynamics of these reactions are disussed and are contrasted with those of the homologous Ca and Sr reactions.