Crystal Structure and DFT Studies of Bis{(E)-2,4-di-tert-butyl-6-((2-fluorophenylimino)methyl) phenolato-N, O-}copper(II)

A novel transition metal complex was synthesized from the reaction between the copper(II)acetate and the Schiff base ligand (E)-2,4-di-tert-butyl-6-((2-fluorophenylimino)methyl)phenol. The title complex was structurally characterized by single crystal X-ray diffraction technique. Crystallographic analysis revealed that the copper(II) center in the investigated complex is four-coordinate, consisting of two imine nitrogen atoms and two phenolic oxygen atoms from two bidentate Schiff bases. The coordination geometry is a distorted seesaw configuration with a τ4 index of 0.33. Hirshfeld surface analysis was employed to investigate the intermolecular contacts within the crystal structure using 3D d_norm surface and 2D fingerprint histograms. The fingerprint plots indicated that the dominant contacts were Van der Waals interactions (H···H, 74.3%), with C···H and H···F interactions also contributing significantly to the overall packing. Density functional theory calculations with the B3LYP/LanL2DZ level were used to calculate the molecular geometric structure of the Cu(II) complex in the ground state. The calculated values were compared with the crystallographic one. Additionally, Natural Bond Orbital (NBO) analysis was performed using the same basis set. The electronic properties of the atoms within the coordination environment and their hyperconjugative interactions were evaluated using NBO analysis.

Graphical Abstract

In this study, the synthesis of a copper(II) complex compound, some DFT calculations, single-crystal X-ray and Hirshfeld surface analyses were performed and interpreted