Redox-switchable magnetic materials based on triarylamine functionalized coordination polymers

• Applicant: Professor Dr. Winfried Plass
• Subject Area: Solid State and Surface Chemistry, Material Synthesis
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 457450704

The project aims to build robust magnetically switchable coordination networks consisting of paramagnetic metal ion fragments and redox-active triarylamine-based linkers, a yet unknown functionality for coordination networks. The preparation of the new materials is based on synthetic methods established in our group. Their functional variation will be further developed on the basis of already available magnetic coordination polymers. The fundamental architecture is based on pillared-layer systems composed of 2-D networks of paramagnetic metal ion fragments and redox-active triaryl linkers combined with appropriate ditopic spacer ligands. The latter enables to introduce additional functionalities into the 3-D networks. The unit of primary interest is the redox-active triaryl linker, which can be easily converted into a cationic radical, as we have already shown in molecular assemblies. The formation of radical linkers leads to 2-D and 3-D magnetic structures, depending on the underlying architecture of the coordination network. This project aims to investigate how the oxidative formation of radical linkers can be controlled in the two underlying network architectures. Fundamental options to achieve this are (i) the chemical or (ii) electrochemical oxidation and (iii) the inclusion of suitable electron acceptors as guest molecules into the pores. In addition, the possibility of generating donor-acceptor aggregates with a combination of triarylamine linkers and electron acceptors as ditope spacer ligands will be explored, which can be optically addressed either directly or via photosensitizers additionally incorporated in the pores. The magnetic, electrochemical, and optical properties, essential for the intended functionality of the materials, will be thoroughly investigated and their interpretation supported by theoretical calculations based on DFT and ab initio methods.

• DFG Programme: Research Grants