Synthesis, X-ray crystal structure of Cu(II) 1D coordination Polymer: In View of Hirshfeld surface, FMO, Molecular electrostatic potential (MEP) and Natural Bond orbital (NBO) analyses

A dynamic area in the realm of contemporary scientific research is the synthesis of molecular systems that exhibit binding abilities for the creation of effective coordination polymeric structures. In addition to the varied network architecture, the rational design and synthesis of metal-organic coordination polymers is currently of great interest because these extended polymeric systems are vital to numerous fields of modern research. In this present research, a new 1D coordination polymer of Cu(II) complex [Cu2(mPzA)2(Bz)]n (1) has been synthesized using two different ligands i.e. 5-methyl-pyrazole-3-carboxylic acid (mPzA) and benzoic acid (Bz). X-ray crystallography study reveals that in the solid-state structure of the title complex, Cu(II) exhibits distorted trigonal bipyramidal geometry. Quantum chemical calculations using density functional theory (DFT) method have been carried out for the complex 1. The computed results further support the experimental findings of the complex adopting a square pyramidal geometry. In the basal plane, the copper atom is bonded through two nitrogen atoms and two oxygen atoms which are bridged between two copper atoms. The axial position is occupied by the oxygen atom of a carboxyl group. Frontier molecular orbital analysis using the global reactivity parameters demonstrates the compound to be stable and less reactive. Moreover, molecular electrostatic potential (MEP) is evaluated using the electron density of the compound to predict the reactive sites. The MEP map clearly indicates strong electrophonic reaction potential of this complex. Natural bond orbital (NBO) analysis has been performed to check the hyperconjugation and thereby stability of the complex 1. NBO analysis revealed the charge delocalization from the bridging oxygen atoms towards copper atoms. The Hirshfeld surface analysis demonstrates absence of π…πstacking interaction and significant contribution of H···H (39.7%) and O···H (24.1%) interactions in building the supramolecular crystal packing.