Novel metal-organic systems based on the oxalate and quinoid ligands with tuned properties suitable for applications
Principal investigator
The project targets at efficient and progressive design of novel and advanced functional materials based on metal-organic complexes. Combination of metal centres with polydentate organic ligands provide colossal, structurally-diverse, platforms possessing a variety of magnetic, electrical, thermal, optical and other properties. In the proposed project, two analogue bridging ligands, oxalate and substituted 2,5-dihydroxyquinonate (DHQ), will be used in the preparation of the coordination polymers of different dimensionality and topology. Their interactions with transition metal cations involve a variety of magnetic phenomena, which can be tuned by highly sensitive selection of structural fragments. The oxalate-based complexes will be studied not only as potential magnetic materials ordering at a certain temperature, but also as the single-source precursors for the preparation of technologically important mixed-metal oxides through the thermal decomposition process. This method of preparing oxides, as compared to conventional solid-state reactions, has several advantages: shorter thermal treatment at lower temperature, without repeating grinding procedures, and the products are more homogeneous. The DHQ complexes will be studied due to their potential for charge transfer, which may lead to materials with reversible magnetic transition. Also, promising class of the ligands are stable semiquinone radicals derived from variously substituted DHQs. So far, their complexes with transition metals are little-known and have not been exploited for design of functional materials. The interdisciplinary nature of the project requires a variety of methods to characterise these advanced materials: single-crystal and powder X-ray diffractions including X-ray charge density studies, thermal analyses (TG/DTA), IR, UV/Vis and EPR spectroscopies, etc. The results obtained will be used to correlate their structure and properties.