Raman and infrared spectra of K 2 PtCl 6 :Ir 4+ crystals

The low temperature Raman and far‐infrared (IR) spectra of solution‐grown crystals of K 2 PtCl 6 :Ir 4+ have been studied. In addition to the strong absorptions of the host compound, a number of weak features were observed. The Raman band at 278 cm −1 has been assigned to ν 2 (E g ) of IrCl   6 2− . An IR‐ and Raman‐active band, observed at 236 cm −1 when K 2 IrBr 6 was used as the dopant, has been assigned to ν(Pt‐Br), A 1 g ′ of [PtCl 4 Br 2 ] 2− . The symmetry of the host compound was lowered by the presence of the dopant ions, resulting in a splitting of some of the IR‐active degenerate modes. Preliminary Raman experiments with K 2 PtCl 6 :Os 4+ indicated that ν 2 of OsCl   6 2−was at 271 cm −1 .