Ligand substitution and conformational effects on the ultrafast luminescent decay of [Re(CO) 3 (phen)(L)] + (L = imidazole, pyridine): non-adiabatic quantum dynamics.

The effects of ligand substitution and conformational flexibility on the ultrafast luminescent decay of [Re(CO)3 (phen)(L)]+ (L = imidazole, pyridine) complexes are investigated by means of density functional theory (DFT/time-dependent DFT (TD-DFT)) electronic structure calculations and non-adiabatic quantum dynamics based on the linear vibronic coupling (LVC) approach including spin-orbit coupling (SOC) applied to the Cs conformers. The optical, luminescent and structural properties are not drastically affected either by the ligand substitution, or by the ligand rotation. However, the occurrence of two conformers, as investigated in detail for the pyridine substituted complex, significantly modifies the early time dynamics below 100 fs and the associated spin-vibronic mechanism.