Studies on vibrational and electronic Raman effects. Resonance Raman spectroscopy of [IrCl6]2–, [IrBr6]2– and [OsBr6]2– ions

The resonance Raman spectra of the [IrCl6]2–, [IrBr6]2– and [OsBr6]2– ions have been recorded with a variety of ion- and dye-laser lines and the following progressions have been observed: v1ν1 to v1= 7, [IrCl6]2–; 6, [IrBr6]2–; 7, [OsBr6]2–: v1ν1+ν2 to v1= 4, [IrCl6]2–; 2, [IrBr6]2–; 1 ? [OsBr6]2–: v1ν1+ν5 to v1= 4, [IrCl6]2–, 4, [IrBr6]2–; 5, [OsBr6]2–. The excitation profiles of several Raman bands of the iridium (IV) complexes have been plotted in detail, and compared with the electronic spectra of the ions in each case. The incidence of electronic Raman spectra ([IrCl6]2– and [OsBr6]2– only) and relaxed fluorescence with available excitation lines is discussed.