Delayed luminescence of Mo atoms during UV excitation of gaseous Mo(CO)6

A luminescence of molybdenum atoms on the e⁷D₅ (44 970 cm^–1) →z⁷P₄⁰ (26 321 cm^–1) transition has been observed during multiphoton UV excitation of gaseous Mo(CO)₆ by excimer lasers. The emission on these transitions arises a few hundred nanoseconds after excitation by the 15-ns pulse from the XeCl laser. The observed luminescence is explained by means of a mechanism which involves the formation of Rydberg Mo atoms and their subsequent relaxation to the state e⁷D₅ (44 970 cm^–1).