A mixed phenoxo and end-on azide bridged dinuclear copper(II) Schiff base complex: synthesis, structure, magnetic characterization and DFT study

A dinuclear copper(II) complex, [(H2O)Cu(L)(μ1,1-N3)Cu(L)]ClO4 [HL = (2-(2-(ethylamino)ethylimino)methyl)-6-ethoxyphenol] has been synthesized and characterized by spectral and elemental analyses. The structure has been confirmed by single crystal X-ray diffraction. Variable temperature (2–300 K) magnetic susceptibility measurements indicate the presence of antiferromagnetic exchange coupling between the copper(II) centers (J = −46.18 cm−1), as also corroborated by DFT calculations (Jtheo = −45.98 cm−1). The calculated spin densities at the copper(II) centers were +0.56 and −0.61, confirming that they are the magnetic centers. An experimental absorption spectrum of the complex has been compared with a normalized absorption spectrum obtained theoretically. Supramolecular interactions in the solid state of the complex have also been characterized with the help of Hirshfeld analysis and the AIM theory.

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