Substituent effects on the photophysical properties of 2,9‐substituted phenanthroline copper(I) complexes: a theoretical investigation
| Autor: | Chantal Daniel, Keiko Takano, Ai Hamano, Christophe Gourlaouen |
|---|---|
| Přispěvatelé: | Institut de Chimie de Strasbourg, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Ochanomizu University |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Coordination sphere
Materials science Ligand Phenanthroline 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Potential energy Atomic and Molecular Physics and Optics Transition state 0104 chemical sciences [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry Crystallography chemistry.chemical_compound chemistry Excited state Potential energy surface Density functional theory [CHIM.COOR]Chemical Sciences/Coordination chemistry Physical and Theoretical Chemistry 0210 nano-technology |
| Zdroj: | ChemPhysChem ChemPhysChem, Wiley-VCH Verlag, 2021, 22, pp.509-515. ⟨10.1002/cphc.202000868⟩ |
| ISSN: | 1439-4235 1439-7641 |
| DOI: | 10.1002/cphc.202000868⟩ |
| Popis: | The electronic and nuclear structures of a series of [Cu(2,9-(X)2 -phen)2 ]+ copper(I) complexes (phen=1,10-phenanthroline; X=H, F, Cl, Br, I, Me, CN) in their ground and excited states are investigated by means of density functional theory (DFT) and time-dependent (TD-DFT) methods. Subsequent Born-Oppenheimer molecular dynamics is used for exploring the T1 potential energy surface (PES). The T1 and S1 energy profiles, which connect the degenerate minima induced by ligand flattening and Cu-N bond symmetry breaking when exciting the molecule are calculated as well as transition state (TS) structures and related energy barriers. Three nuclear motions drive the photophysics, namely the coordination sphere asymmetric breathing, the well-documented pseudo Jahn-Teller (PJT) distortion and the bending of the phen ligands. This theoretical study reveals the limit of the static picture based on potential energy surfaces minima and transition states for interpreting the luminescent and TADF properties of this class of molecules. Whereas minor asymmetric Cu-N bonds breathing accompanies the metal-to-ligand-charge-transfer re-localization over one or the other phen ligand, the three nuclear movements participate to the flattening of the electronically excited complexes. This leads to negligible energy barriers whatever the ligand X for the first process and significant ligand dependent energy barriers for the formation of the flattened conformers. Born-Oppenheimer (BO) dynamics simulation of the structural evolution on the T1 PES over 11 ps at 300 K confirms the fast backwards and forwards motion of the phenanthroline within 200-300 fs period and corroborates the presence of metastable C2 structures. |
| Databáze: | OpenAIRE |
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