晶体-塑晶相驱动的spin-Peierls-tye低维分子磁体的磁性质研究

In this project, the ionic plastic crystal organic cation with long alkyl and alkoxy chains were synthesized and characterized, and were brought in the magnetic [M(dithiolato)2]- (M = Ni, Pd or Pt ion) spin system for the building spin-Peierls-type compounds. The crystal structure, elecochemical properties (temperature dependences of conductivity ), magnetic properties (temperature dependences of magnetic susceptibility and EPR ) and thermodynamic behavior (DSC) of the target compounds will be investigated to establish structure-properties correction, the intrinsic dring force of the spin-Peierls-type transition of the target compounds will be further investigated. We will further select some compounds with the spin-Peierls-type transition temperature at around room temperature as the research system, of these compounds, the magnetic and electrical properties under high pressure will be explored. The magnetic exchange model of intermolecular between the [M(mnt)2]- will be established based on crystal structure. Exploring the correlation between the packing structure, the magnetic properties, as well as other fuctional properties in theory. Our results will shed a light on the design and synthesis of a new functional molecular system.

本项目研究内容包括：设计合成不同烷基链长和拓扑结构的离子塑晶化合物，制备塑晶类有机阳离子与双-(二硫烯)Ni、Pd或Pt的负一价阴离子形成的离子对化合物。对合成的目标化合物，在完成化学分析和各种波谱表征的基础上，研究其晶体结构、电学性质（变温电导率）、磁学性质（变温磁化率和EPR谱学性质）和热力学行为（DSC等）。研究目标化合物的分子结构、晶体堆积结构、自旋转换性质、热力学性质等结构和功能之间的关系，探讨spin-Peierls-type 磁相变的内在驱动力。优化出spin-Peierls-type 转变温度在室温附近的目标化合物，进一步开展材料的高压下磁电性质研究。基于单晶结构信息，建立分子间磁交换模型，分析材料的能带结构，从理论上探索结构与磁、电等功能性质之间的相关性。本项目研究结果将对新的分子材料设计和功能性开发等方面具有重要的科学价值。