Table 1.

Electrochemical and optical properties of Zn–dipyrrin complexes.^a

PSs	E ox/V	E red1/V	E red2/V	ΔEredb/V	E S 00 c/eV	ΔEred – E00	ΔGcsd/eV
Z-1	0.75	−1.62	−1.84	2.37	2.51	−0.14	−0.63
Z-2	0.77	−1.58	−1.81	2.35	2.48	−0.13	−0.62
Z-3	0.83	−1.47	−1.73	2.30	2.46	−0.16	−0.65
Z-4	0.78	−1.59	−1.84	2.37	2.48	−0.11	−0.60
Z-5	0.79	−1.45	−1.67	2.33	2.46	−0.13	−0.61
Z-6	0.81	−1.56	−1.80	2.37	2.48	−0.11	−0.60

^aThe experiments were carried out in deaerated acetonitrile solution containing 0.5 mM of PS with ferrocene (Fc) and 0.1 M of Bu₄NPF₆. Fc was used as an internal reference (E_1/2 = +0.4 V (Fc⁺/Fc) vs. SCE). Glassy carbon electrode, Ag/AgNO₃ and Pt silk were used as the working electrode, reference electrode and counter electrode, respectively. Scan rate: 0.05 V/s. ^bElectrochemical gap determined by the energy difference between the first oxidation potential and the first reduction potential. ^cThe optical ¹LE gap is determined by the cross point of the UV–vis absorption and fluorescence emission spectra of Zn PSs in acetonitrile. ^dThe Gibbs free energy changes of the SBCT process in acetonitrile.