plokiahelats

Plokiahelats are a proposed class of multinuclear metallosupramolecular assemblies in coordination chemistry. They consist of several metal centers joined by polydentate ligands to form networked structures. The term blends poly- ("many") with chelate, and appears in recent reviews to describe families of related compounds rather than a single substance.

Structure is topology-driven: plokiahelats can form discrete clusters, one-dimensional chains, or two- and three-dimensional networks, depending on ligand design and metal choice. Ligands with multiple binding sites bridge metal nodes, creating high-nuclearity constructs and tunable connectivity. Common metals include Fe, Cu, Zn, Co, and Mn; ligands favor rigidity and preorganization.

Synthesis and characterization: these assemblies are typically prepared by self-assembly from metal salts and designed ligands under solvothermal or slow-diffusion conditions. Crystallography reveals topology; complementary techniques such as magnetometry and surface area analysis assess properties and porosity. Control of stoichiometry and reaction conditions is crucial for reproducibility.

Properties and applications: plokiahelats exhibit adjustable stability, electronic communication among metal centers, and, in some cases, porosity suitable for gas uptake. Potential uses include catalysis (water splitting, CO2 reduction), gas storage, sensing, and components of supramolecular electronics. The field emphasizes modular design and scalable synthesis.

Status: the term remains niche and somewhat informal, with ongoing debate about its scope. Some researchers classify plokiahelats as a subclass of coordination polymers or metal–organic frameworks, while others treat them as distinct multinuclear chelate networks. See also: coordination polymers, metal-organic frameworks, multinuclear coordination compounds, supramolecular chemistry.