A cathodoluminescence broad-band which was observed in the spectrum was attributed to the well-known 4f65d → 4f7 electronic transition of the Eu2+ ions and to the so-called off-center π luminescence as modified by the F center absorption band (F center self-absorption). By studying cathodoluminescence emissions at various temperatures, it was found that the Eu ions interfered with the dynamics of defect formation in KCl. The cathodoluminescence images also revealed optically active zones in both doped and pure samples.

Cathodoluminescence and Optically Active Regions of Intrinsic and Induced Defects in Eu2+-Doped KCl Crystals. R.Aceves, R.Pérez-Salas, U.Pal: Physica Status Solidi B, 2002, 233[2], 364-72