Premium
Photoluminescence of Seven‐Coordinate Zirconium and Hafnium Complexes with 2,2′‐Pyridylpyrrolide Ligands
Author(s) -
Zhang Yu,
Akhmedov Novruz G.,
Petersen Jeffrey L.,
Milsmann Carsten
Publication year - 2019
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201804671
Subject(s) - phosphorescence , zirconium , ligand (biochemistry) , chemistry , photoluminescence , excited state , photochemistry , hafnium , absorption (acoustics) , luminescence , density functional theory , fluorescence , absorption band , absorption spectroscopy , visible spectrum , materials science , inorganic chemistry , computational chemistry , optoelectronics , biochemistry , physics , receptor , quantum mechanics , nuclear physics , optics , composite material
Abstract Luminescent seven‐coordinated zirconium and hafnium complexes bearing three mono‐anionic 2,2′‐pyridylpyrrolide ligands and one chloride were synthesized. Solid‐state structures and the dynamic behaviors in solution were probed by X‐ray crystallography and variable temperature 1 H NMR experiments, respectively. Absorption spectroscopy and time‐dependent density functional theory (TD‐DFT) calculations supported a hybrid of ligand‐to‐metal charge transfer (LMCT)/ligand‐to‐ligand charge transfer (LLCT) for the visible light absorption band. The complexes ( Me PMP Me ) 3 MCl (M=Zr, Hf, Me PMP Me =3,5‐dimethyl‐2‐(2‐pyridyl)pyrrolide) are emissive in solution at room temperature upon irradiation with visible light due to a combination of phosphorescence and fluorescence characterized by excited state lifetimes in the μs and low to sub‐ns timescale, respectively. Electrochemical experiments revealed that the zirconium complex possesses a reversible redox event under highly reducing condition (−2.29 V vs. Fc +/0 ).