Luminescence of s2 ions in CsCdBr3 and CsMgCl3

The luminescence properties of Bi3+ in CsMgCl3, of Bi3+ and Pb2+ in CsCdBr3, and of undoped CsCdBr3 are reported. For CsMgCl3Bi3+ two luminescent centers are observed. One is ascribed to isolated Bi3+ ions and the other to a Bi3+-vacancy-Bi3+ complex. For CsCdBr3 only one luminescent center is observed. The Stokes shift amounts 2.1 eV and the quenching temperature is low (∼40 K). Undoped CsCdBr3 shows also luminescence which seems to be related to structural disorder. Finally, the luminescence properties of CsCdBr3Pb2+ are discussed. Below 80 K luminescence of intrinsic Pb2+ ions is observed. This luminescence is in the green spectral region. The luminescence above 100 K is ascribed to Pb2+ ions in a layer of slightly disordered bromine ions: excitation occurs in these bromine ions and is transferred to Pb2+ ions.