Electronic and Geometric Structures of Paramagnetic Diazadiene Complexes of Lithium and Sodium

摘要

The electronic and molecular structures of the lithium and sodium complexes of 1,4‐bis(2,6‐diisopropylphenyl)‐2,3‐dimethyl‐1,4‐diazabutadiene ( Me2 DAD Dipp ) were fully characterized by using a multi‐frequency electron paramagnetic resonance (EPR) spectroscopy approach and crystallography, together with density functional theory (DFT) calculations. EPR measurements, using T 1 relaxation‐time‐filtered pulse EPR spectroscopy, revealed the diagonal elements of the A and g tensors for the metal and ligand sites. It was found that the central metals in the lithium complexes had sizable contributions to the SOMO, whereas this contribution was less strongly observed for the sodium complex. Such strong contributions were attributed to structural specifications (e.g. geometrical data and atomic size) rather than electronic effects. A good DAD : The electronic and molecular structures of the Li and Na complexes of 1,4‐bis(2,6‐diisopropylphenyl)‐2,3‐dimethyl‐1,4‐diazabutadiene ( Me2 DAD Dipp ) are fully characterized by EPR spectroscopy, crystallography, and DFT calculations. The temperature‐dependent electron spin relaxation processes are shown, and the application of relaxation filters reveals the paramagnetic properties of the metal and ligand sites of the complexes.