Xenon excimer compounds with oxygen in inert-gas crystal matrices

Abstract

Xenon excimer compounds with oxygen in low-temperature inert-gas (R) crystal matrices are investigated. The transformation of the excimer emission spectrum as a reslt of a change in the Xe concentration is analyzed. It is shown that the luminescence band with a peak near 1.7 eV could be due to the superposition of two bands with Emax=1.8 and 1.72 eV. The higher-energy band with Emax=1.8 eV is observed at low xenon concentration, and it can be interpreted as a transition from the 11Π state of the complex XeO* to the lowest state XeO X3Π. The band with Emax=1.72 eV, which predominates in the intrinsic Xe matrix with oxygen impurity and high-concentrated solutions R+Xe+O2 is attributed to emission of the triatomic excimer Xe2O*. A comparative analysis of the experimental data and theoretical calculations, obtained for analogous compounds of xenon halides and hydrides as well as the xenon compound with the isoelectronic S atom, is performed. The results suggest that the 3.33 and 3.58 eV bands observed in the xenon matrix belong to emission of charge-transfer complexes Xe2+O− and Xe2+S−.