Key points are not available for this paper at this time.
The complex Ru (bipy) 23 (µ3-L) 3+ (H6L = hexahydroxytriphenylene), in which the tris-dioxolene bridging ligand is formally in the tris-semiquinone oxidation state sq, sq, sq, undergoes three reversible ligand-centred oxidations to the q, q, q state (q = quinone) ; it exhibits very strong NIR absorption arising from Ru → L charge transfer whose maximum wavelength may be tuned over a wide range according to oxidation state.
Barthram et al. (Thu,) studied this question.