Understanding the magnetic properties of room temperature magnets synthesized by post-synthetic redox methodology

A new benchmark has been discovered by our team regarding molecule-based magnets with the highest ordering temperature. The post-synthetic reduction of the 2D Cr(pyz)2Cl2 (pyz = pyrazine) network generates a material showing hysteresis up to 515 K. For this, we have begun tuning the properties through the post-synthetic reductions of Cr(pyz)2I2 by replacing the chloride ligands with its larger congener iodide. Moreover, partial reduction of these systems opens a gateway to mixed-valence states. To overcome the challenges faced with these materials in correlating their properties with both the solid-state and electronic structure, this proposal aims to shed light on structure-property relationships of this system through a series of partially and fully reduced networks through the collective techniques of high-resolution powder X-ray diffraction (HR-PXRD), X-ray absorption near edge structure (XANES) and X-ray magnetic circular dichroism (XMCD).

我们团队针对具有最高有序温度的分子基磁体（molecule-based magnets）构建了全新基准数据集。对二维Cr(pyz)₂Cl₂（吡嗪(pyz)）网络实施合成后还原，可得到磁滞上限达515 K的材料。为此，我们通过将氯配体替换为更大的同系物碘配体，对Cr(pyz)₂I₂开展合成后还原以调控其性能。此外，对这类体系进行部分还原可获得混合价态材料。为克服这类材料在关联其固态与电子结构与性能时面临的挑战，本研究拟通过高分辨粉末X射线衍射（HR-PXRD）、X射线吸收近边结构（XANES）与X射线磁圆二色谱（XMCD）等联用技术，对该体系的部分还原与完全还原网络展开系列研究，以阐明其构效关系（structure-property relationships）。