Quinone-based single-molecule magnets

• Applicants: Professor Dr. Biprajit Sarkar; Professor Dr. Joris van Slageren
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation ; Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 407333568

This project sees the continuation of the collaboration between both applicants. The aim is to develop radical bridged di- and trinuclear transition metal single-molecule magnets with high energy barriers toward relaxation of the magnetic moment and strong coercivities. Such complexes may find application in magnetic data storage and further the understanding of the magnetic properties of metal-radical complexes. To this end we will first optimize the promising single molecule magnet building blocks we have previously identified. Subsequently, we will develop and investigate di- and trinuclear complexes based on these building blocks, where the radical nature of the bridging ligands engenders strong magnetic couplings. The strong couplings are expected to suppress underbarrier relaxation processes which are detrimental for the coercivity required for magnetic bistability. We exploit the complementary competences and expertise of the applicants. Thus, the Sarkar group will design all building blocks and polynuclear complexes. They will develop and optimize the syntheses and isolate and characterize the products. Finally, they will study the redox chemistry of the complexes and isolate and characterize the redox products with radical bridges. The Van Slageren will carry out all static and dynamic magnetic investigations to investigate the magnetic anisotropy and exchange couplings, as well as the magnetization relaxation behaviour. They will also carry out in-depth spectroscopic studies using advanced magnetic resonance and optical techniques to establish the relation between the magnetic properties and the electronic structures of the complexes.

• DFG Programme: Research Grants