Synthesis, characterization, crystallographic aspects, Fukui function, and photodynamic antifungal chemotherapy investigation of Cd (II)-tricyanomethanide coordination polymer: Insights from DFT

Abstract

This study delves into the synthesis, crystal structure, structural topology, photodynamic antifungal therapy (PACT), and DFT-based investigations of one [Cd(TCM)2]n coordination polymer (TCM = tricyanomethanide). The complex was structurally characterized using elemental, IR/Raman, UV–Visible spectroscopy, PXRD, EDXSEM, and X-ray diffraction. X-ray structure divulges that the complex crystallizes in the orthorhombic space group Pmna where Cd(II) centres assume octahedral geometry and are coordinated by six N atoms from six TCM. The topology analysis reveals an sqc8 topology with Cd(II) occupying the nodes, where the TCM connectors form edges. The crystal packing consists of unique nitrile⋅⋅⋅nitrile interactions at 3.276 Å. The crystal packing is confirmed by Hirshfeld surface (HS) and 2D fingerprint plots. The Cd⋅⋅⋅N contact makes up 35.1% of the packing, while the C⋅⋅⋅C and N⋅⋅⋅N contacts contribute 21.2% and 20.6%, respectively. The complex DFT optimization was contrived in B3LYP, HF, and M06-2x methods employing the 3–21 g, lanl2dz, and sto-3 g level of basis sets. Here chemical reactivity is supported by the HOMO-LUMO energy gap and ESP. The electrophilic (E + ) and nucleophilic (Nu-) sites were examined by Fukui function values (fx+, fx - , and f 0). The NLO parameters support the complex optical properties. The molecular docking simulation (MD) and protein–ligand interactions profiler (PLIP) has shown promising results in studying the relationship between complex and cancer proteins at a biological level. The article vivdly discusses the photodynamic antifungal therapy’s effectiveness using MIC value against antibiotic-resistant strains when used with complex, TCM, and metal salts. The most effective mechanisms include membrane disruption, ROS, and cell cycle arrest.