Redox-switchable magnetic materials based on triarylamine functionalized coordination polymers

该项目旨在建立强大的磁性可切换配位网络，包括顺磁性金属离子碎片和氧化还原活性三芳胺连接物，这是一个未知的配位网络功能。新材料的制备是基于我们小组建立的合成方法。它们的功能变化将在现有磁配位聚合物的基础上进一步发展。其基本结构是基于由顺磁性金属离子碎片和氧化还原活性三芳基连接剂与适当的双位间隔配体组成的二维网络组成的柱状层体系。后者能够在三维网络中引入额外的功能。主要感兴趣的单元是氧化还原活性的三芳基连接体，它可以很容易地转化为阳离子自由基，正如我们已经在分子组装中展示的那样。自由基连接体的形成导致二维和三维磁性结构，这取决于配位网络的底层结构。本项目旨在研究如何在两种潜在的网络结构中控制自由基连接物的氧化形成。实现这一目标的基本选择是(i)化学或（ii）电化学氧化和（iii）将合适的电子受体作为客体分子包含到孔隙中。此外，还将探索三芳胺连接体和电子受体作为二键空间配体的组合产生供体-受体聚集体的可能性，这可以直接或通过在孔中添加光敏剂进行光学寻址。磁性、电化学和光学性质对材料的预期功能至关重要，将被彻底研究，并通过基于DFT和从头算方法的理论计算来解释它们。

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.