Emission and excitation spectra of rare gas hydride trimers in rare gas matrices

Abstract

The excitation and emission spectra of Ar 2H(D) in Ar, Kr 2H(D) in Kr and Xe 2H(D) in Ar, Kr, Xe were observed by doping rare gas solids with H 2 or D 2 and subsequent photolysis. The emission lines are typical bound-free transitions with a linewidth very similar to the Rg 2 emission lines in rare gas solids. The excitation spectra of Xe 2H(D) in Ar and Kr consist of a single vibrational progression which can be interpreted as a direct excitation of the emitting electronic state. In contrast to that, the excitation spectra of Kr 2H(D) in Kr and Xe 2H(D) in Xe show a pronounced fine structure with vibrational progressions and cannot be assigned to a single excited electronic state. In analogy to the rare gas halides, these data are discussed within the framework of two existing theoretical models developed for the halides.