Figure 2.

(a) Absorption spectra for the Ru-ip-nT complexes in water. (b) Excitation spectra of the Ru-ip-nT complexes in water at 640 nm emission normalized to the MLCT band at 480 nm (*, left); bi-exponential emission decay of Ru-ip-2T with lifetimes of 0.6 μs and 11 μs at 630 nm (right); Inset: Emission spectra of Ru-ip-nT complexes normalized to their respective maxima. (c) Nanosecond TA spectra of Ru-ip-nT complexes in aerated water normalized to their respective maxima at λ_ex.: 410 nm at 300 ns. (d) Relationship between the PI values (black y-axis), singlet-oxygen quantum yield Ф _Δ (red y-axis) in aerated MeCN (excitation at 450 nm) and fluorescence quantum yield Ф _em. (blue y-axis) in deaerated water (excitation at 450 nm) with increasing thiophene chain length (x-axis).^[1] The PI is defined as the ratio of EC_{50 dark} to EC_{50 visible light} values in SK-MEL-28 cells.