A new record excited state 3 MLCT lifetime for metalorganic iron( ii ) complexes

Li Liu (1) , Thibaut Duchanois (2) , Thibaud Etienne (2) , Antonio Monari (2) , Marc Beley (2) , Xavier Assfeld (2) , Stefan Haacke (1) , Philippe C Gros (2)

1 IPCMS - Institut de Physique et Chimie des Matériaux de Strasbourg
2 SRSMC - Structure et Réactivité des Systèmes Moléculaires Complexes

Herein we report the synthesis and time-resolved spectroscopic characterization of an homoleptic Fe(II) complex exhibiting a record 26 ps 3 MLCT lifetime promoted by benzimidazolylidene-based ligands. Time Dependent Density Functional molecular modeling of the triplet excited state manifold clearly reveals that, at equilibrium geometries, the lowest 3 MC state lies higher in energy than the lowest 3 MLCT one. This unprecedented energetic reversal in iron complexes series, with the stabilization of the charge-transfer state, opens new perspectives towards iron made excitonic and photonic devices, hampering the deactivation of the excitation via metal centered channels.

Domaines: Chimie-Physique [physics.chem-ph]; Chimie de coordination

Li Liu, Thibaut Duchanois, Thibaud Etienne, Antonio Monari, Marc Beley, et al.. A new record excited state 3 MLCT lifetime for metalorganic iron( ii ) complexes. Physical Chemistry Chemical Physics, 2016, 18 (18), pp.12550-12556. ⟨10.1039/C6CP01418F⟩. ⟨hal-01812755⟩