Synergistic Experimental-Cum-Theoretical Investigation of Supramolecular Interactions in a Novel Binuclear Cu(II) Complex

Abstract

This work presents a comprehensive experimental and computational investigation of the Cu(II)-MPCMA complex (where MPCMA = methyl 5-methylpyrazole-3-carboxylate) CCDC: 869805, focusing on its crystal structure, intermolecular interactions, and surface characteristics. The binuclear coordination compound [Cu₂(MPCMA)₂Cl₂] was synthesized and characterized by single-crystal x-ray diffraction, Raman spectroscopy, and solid-state UV–visible absorption measurements. Crystallographic analysis shows that the Cu(II)-MPCMA complex adopts a distorted octahedral geometry, with MPCMA acting as a bidentate ligand. Density functional theory (DFT) and time-dependent DFT calculations were carried out to probe its electronic and spectroscopic properties. A comparison between computed and experimental bond lengths and angles resulted in good agreement, that supports the reliability of the computational approach. Further, we analyzed Hirshfeld surfaces, which provide detailed insights into close intermolecular contacts and the nature of the dominant interactions.