Table 3. Calculated (B3LYP/{Lanl2dz + 6-31G(d)}) energy gaps (ΔE/eV) in P2, H42, H42–Na2 and H42–Mg2. The lowest LUMO levels are highlighted in bold.
| Molecule | ΔES–T a | ΔE[HOMO–Ru – LUMO+x]
b
|
|
| LUMO (dpbpy) | LUMO (crown/bpy) | ||
| [Ru(bpy)2(dpbpy)]2+ (P2) | 2.000 | 3.324 | 3.712 |
| [Ru(5-crown-phen)2(dpbpy)]2+ (H42) | 2.051 | 3.367 | 3.731 |
| [Ru(Na-5-crown-phen)2(dpbpy)]4+ (H42–Na2) | 2.111 | 3.503 | 3.663 |
| [Ru(Mg-5-crown-phen)2(dpbpy)]4+ (H42–Mg2) | 2.190 | 3.510 | 3.616 |
aSeparation between ground state singlet and triplet excited state.
bSeparation between ruthenium based HOMO and LUMO of relevant ligand.