Excited-state LIF Spectroscopy of Hg and Zn Molecules - The Path to New Excimer Lasers?

Publisher Summary There has been a revival of interest in the spectroscopy of Group 2b excimers because of the possibility of laser action in the blue-green spectral region. In the past, various attempts to produce laser action in Hg2 have been unsuccessful because of excited-state absorption from either the upper laser-level or meta stable levels in equilibrium with it. The spectroscopy of the Hg2 excimer has been investigated systematically during recent years using pump method and probe method, and numerous bound excited states and transitions between pump method and probe method have been identified. Analysis of vibrational structures of the fluorescence and excitation bands yielded vibrational frequencies, anharmonicities, energy separations between the electronic states, and relative equilibrium inter nuclear separations. Recent high-resolution laser-spectroscopic studies of mono isotopic Hg 2 produced partial resolution of the rotational structure. Some non-linearity in the line-separations is due to the mode structure of the probe-laser output.