Electrochemical results for complexes 1–4 and co-complexes 1–4·5.

System	E ox a (V)	E red a (V)	ΔEa (V)	(com)E0–0b (eV)	E 0–0 c (eV)	E(PS*/PS−)d (V)	E(PS*/PS+)e (V)
1	1.17	−1.51	2.68	3.16	2.81	1.30	−1.64
1·5 (1 : 1)	1.27	−1.50	2.77	3.26	2.84	1.34	−1.57
2	0.82	−1.49	2.31	2.95	2.58	1.09	−1.76
2·5 (1 : 1)	0.85	−1.51	2.36	3.07	2.59	1.08	−1.74
3	0.67	−1.52	2.19	2.83	2.36	0.84	−1.69
3·5 (1 : 1)	0.71	−1.50	2.21	2.96	2.39	0.89	−1.68
4	0.54	−1.51	2.05	2.79	2.26	0.75	−1.72
4·5 (1 : 1)	0.61	−1.48	2.09	2.84	2.28	0.80	−1.67

^aAll samples were prepped and studied in an argon flushed glove box in degassed, dry CHCl₃. Further details of electrodes and apparatus can be found in ESI S1.

^b(com)E_0–0 calculated from the computationally obtained HOMO–LUMO gap.

^c E _0–0 was calculated from the crossover of normalised absorption and emission spectra.

^d E(PS*/PS⁻) = E_red + E_0–0.

^e E(PS*/PS⁺) = E_ox − E_0–0.