Table 4. Electrochemical Properties As Measured with Cyclic Voltammetry and Theoretical HOMO – LUMO Gaps Calculated by DFTa.
| Eox (V) | Ipa/Ipc | Ered (V) | Ipc/Ipa | ΔEexp (V)c | ΔEth (eV)d | ||
|---|---|---|---|---|---|---|---|
| [Ru(phbpy)(bpy)(DMSO-κS)]PF6 | [1]PF6 | +0.30 | 0.99 | –1.90 | 1.47 | 2.20 | 3.65 |
| [Ru(phbpy)(phen)(DMSO-κS)]PF6 | [2]PF6 | +0.32 | 1.02 | –1.89 | 1.11 | 2.21 | 3.65 |
| [Ru(phbpy)(dpq)(DMSO-κS)]PF6 | [3]PF6 | +0.29 | 1.01 | –1.87, −1.95 | 0.66, 2.23 | 2.16 | 3.57 |
| [Ru(phbpy)(dppz)(DMSO-κS)]PF6 | [4]PF6 | +0.35 | 1.04 | –1.43, −2.00 | 1.03 | 1.78 | 3.13 |
| [Ru(phbpy)(dppn)(DMSO-κS)]PF6 | [5]PF6 | +0.36 | 1.05 | –1.21, −1.82, −2.01 | 1.07, 1.52 | 1.57 | 2.86 |
| [Ru(phbpy)(bpy)(CD3CN)]PF6 | [6]PF6 | 0.00 | 1.00 | –2.05 | 1.34 | 2.05 | |
| [Ru(phbpy)(phen)(CD3CN)]PF6 | [7]PF6 | +0.02 | 1.04 | –2.05 | 1.38 | 2.07 | |
| [Ru(tpy)(bpy)(DMSO)](PF6)2 | [9](PF6)2 | +1.23b | –1.48 | 1.00 | 2.71 | ||
| [Ru(tpy)(bpy)(MeCN)](PF6)2 | [10](PF6)2 | +0.92 | 0.95 | –1.67 | 1.06 | 2.59 | 4.12 |
a
Potentials given vs. Fc0/Fc+ in MeCN with 0.1 M [Bu4N]PF6 as supporting electrolyte. Complexes were measured at 298 K with a scan rate of 100 mV s–1, with the exception of [4]PF6, [6]PF6 [7]PF6, and [9]PF6 which were measured at 200 mV s–1.
b
Epa.
c
ΔEth = ELUMO – EHOMO at the DFT/PBE0/TZP/COSMO level in water.
d
ΔEexp = Eox – Ered,.