Fine structure in the emission spectrum of [Ru(bpy)3] (PF6)2 single crystals

For the first time, highly resolved polarized emission spectra of single-crystal [Ru(bpy)3](PF6)2 are presented. At low temperatures (T<20 K) we observed fine structure on the blue side of the emission spectrum with a typical halfwidth of ⩽5 cm−1. The spectral properties of the sharp emission lines and their temperature dependences allow us to assign two zero-phonon lines corresponding to 1E′ → A′1 at 17809 cm−1 and to 2E′ → A′1 at 17816 cm−4 in the D′3 symmetry group.