线性形状的Re(I) 寡合物和聚合物的系统合成,分离和光物理特性,具有2-20个单位
Youhei Yamamoto1, Shuhei Sawa, Yusuke Funada
1Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1-E1-9 O-okayama, Meguro-ku, Tokyo 152-8551, Japan.
Journal of the American Chemical Society
|October 14, 2008
概括
研究人员开发了带有联体的线性 () 聚合物. 这些排放性材料在溶液中表现出高效的能量传输和分子间聚合,为新的光电子应用铺平了道路.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 光物理学的光学物理学
背景情况:
- ((I) 复合物以其光发光特性而闻名.
- 线性寡合物和聚合物具有独特的电子和结构特征.
- 氨酸连接体在桥梁金属中心和调性质方面发挥着至关重要的作用.
研究的目的:
- 合成和表征由双酸联体桥接的线性 (((I) 寡合体和聚合物.
- 为了研究光物理性质,包括排放和能量转移动态.
- 探索这些扩展的 (I) 系统的结构特征和溶液行为.
主要方法:
- 系统合成 (I) 寡合体和聚合物.
- 使用尺寸排除色谱 (SEC) 进行隔离和净化.
- 通过NMR,IR,质谱,分析SEC和元素分析进行表征.
- 用于结构确定的X射线晶体学.
- 光发光谱学和辐射衰变测量.
主要成果:
- 成功合成了不同长度 (n=0-18) 的线性(I) 寡合体和聚合物.
- 结构分析揭示了链接间和pi-pi相互作用.
- 所有合成的化合物都表现出室温溶液排放.
- 与二极体相比,在较长的寡合体/聚合物中观察到红移排放.
- 证明了从边缘到内部单位的高效能量传输,速度常数为 (0.9-2.5) x 10^8 秒 (-1).
- 对于较长的聚合物来说,存在分子间聚合在溶液中的证据.
结论:
- 开发的合成路径提供了对精确定义的线性 (I) 组件的访问.
- 高效的分子内能量转移是这些扩展系统的一个关键特征.
- 分子间聚合会影响较长的 (I) 聚合物的溶液行为.
- 这些发现有助于理解金属聚合物中的结构-性质关系,用于潜在的光电子应用.
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