Resonant luminescence line narrowing of the R lines in [Rh(bpy) 3] (PF 6) 3:Cr(III)

Abstract

A rigorous study of the R line luminescence of the title compound is presented. From site-selective spectroscopy, the temperature dependence of the luminescence, and the homogeneous line width of the R 2 line, a 18.5 cm -1 2E splitting for the majority sites of the title compound is confirmed. About 20% of the Cr(bpy) 3+ 3 chromophores are in slightly different sites leading to a variation of the 2E splitting of about 10%. From resonant FLN experiments in external magnetic fields up to 3 T a g ∥ = -1.76±0.01 value of the lowest-excited state, 2E( E ), is deduced. Relatively large homogeneous line widths of 0.01 and 1.8 cm -1 are found for the R 1 and R 2 lines at 1.5 K, respectively. The direct relaxation process between the split 2E components is the main contribution to the widths of the R lines between 10 and 100 K.