从状联体到状协调聚合物:自发分辨率,弱铁磁性和拓铁磁性
En-Qing Gao1, Yan-Feng Yue, Shi-Qiang Bai
1State Key Lab of Rare Earth Materials Chemistry and Applications & PKU-HKU Joint Lab in Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, People's Republic of China.
Journal of the American Chemical Society
|February 5, 2004
概括
阿基拉尔二酸连接物诱导协调聚合物中的结构性性,导致自发解离,形成同基拉尔一维链和二维层. 这些性材料表现出不同的磁性行为,包括超磁性和弱铁磁性.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 在协调聚合物中的性对于不对称催化和性识别中的应用至关重要.
- 开发方法来诱导和控制协调聚合物中的奇拉性是一个活跃的研究领域.
- 亚齐多桥接协调聚合物提供了多功能结构动图和可调节的磁性质.
研究的目的:
- 为了合成和表征新型的和协调聚合物,使用阿基拉尔二酸连接物.
- 调查这些协调聚合物的构造性性诱导.
- 探索诱导性性,结构特征和磁性特性之间的关系.
主要方法:
- 使用二酸连接物 (L1-L4) 合成五种亚酸桥接协调聚合物.
- 结晶学表征以确定结构和性.
- 测量磁性特性以分析磁性行为.
主要成果:
- 干L1和L2诱导了自发解离,形成具有三角形或双螺旋形状单元的同体状1D链.
- 连接物L3导致部分自发解离,形成 homochiral 2D 层,产生种族和凝聚体形式.
- 由于中心对称桥接,联结物L4没有诱导奇拉性,由此产生的二维层是无奇拉的.
- 协调聚合物表现出不同的磁性行为:元磁性 (1),1D反铁磁性 (2) 和旋转偏向的弱铁磁性 (3a,3b,4).
结论:
- 阿希拉尔二酸连接物可以有效地诱导亚齐多桥接协调聚合物中的构造性性.
- 连接体置换的程度会影响自发解离的发生和性结构的维度.
- 由此产生的形结构表现出不同的可调节的磁性,突出了结构和磁性之间的相互作用.
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