This research is devoted to an analysis of continuous luminescence spectra of argon and neon crystals in the ranges 4–7 and 9–17 eV, respectively. The experimental results of this research are compared comprehensively with the data on the gaseous phase and with the luminescence of exciplexes of inert-gas halogenides. It is proposed on the basis of the detailed comparison of different experimental data that the continuum with a peak at 6.2 eV can be identified with radiation decay of the excimer complexAr2+O−.The formation of a similar exciplexNe2+O−with charge transfer is observed in the neon matrix doped strongly with oxygen. ©1998 American Institute of Physics.