Elucidating the Crystal Structures of Heteronuclear Salen Complexes Cul-Cdx2 2 With Experimental and Computational Methods

Abstract

Two novel heteronuclear salen-type complexes, CuL1-CdCl2 1-CdCl 2 and CuL2-CdI2, 2-CdI 2 , have been successfully synthesized and characterized. The characterization processes utilized single-crystal X-ray diffraction, elemental, and FT-IR analysis, revealing the structural properties of the complexes. In both complexes, the Cu(II) ion exhibited an approximate square planar geometry (CuN2O2), 2 O 2 ), where the deprotonated phenoxide-type ligand L 2- coordinated to form N2O2. 2 O 2 . Conversely, For CuL1-CdCl2, 1-CdCl 2 , the Cd(II) ion displayed a trigonal prismatic geometry, surrounded by two chlorine atoms and four oxygen atoms. Intermolecular and intramolecular interactions within the complex were facilitated by C-H & sdot;& sdot;& sdot;Cl, - H & sdot;& sdot;& sdot; Cl, C-H & sdot;& sdot;& sdot;N, - H & sdot;& sdot;& sdot; N, and C-H & sdot;& sdot;& sdot;O - H & sdot;& sdot;& sdot; O hydrogen bondings. For CuL2-CdCl2, 2-CdCl 2 , the Cd(II) ion displayed a trigonal prismatic geometry, surrounded by two iodine atoms and four oxygen atoms. Intermolecular interactions within the complex were facilitated by weak C-H & sdot;& sdot;& sdot;I - H & sdot;& sdot;& sdot; I hydrogen bonding, while the overall stability of the framework was ensured through weak pi & sdot;& sdot;& sdot;pi pi stacking interactions. According to the Hirshfeld surface analysis results, the H & sdot;& sdot;& sdot; H contacts constitute a large part of the total surface area for both complexes; this highlights the importance of hydrogen bond interactions in stabilizing the crystal arrangement. The theoretical analysis of the complexes was executed by using Becke's three-parameter hybrid functional for the exchange component and the Lee-Yang-Parr (LYP) correlation function with the LanL2DZ basis set to achieve the optimized geometrical parameters. The results showed that experimental and theoretical calculations were in agreement.