强烈发光的金 (I) -银 (I) 集群复合体具有可调节的结构特征
Quan-Ming Wang1, Young-A Lee, Olga Crespo
1Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
Journal of the American Chemical Society
|August 5, 2004
概括
具有独特四面体结构的新发光金银星团显示可调节的发射颜色从蓝色到色,这取决于桥接的素原子. 这项研究引入了第一个金氧发光系统.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
背景情况:
- 黄金 (I) 和银 (I) 复合物以其有趣的光物理特性而闻名.
- 金属性,金属中心之间的有吸引力的相互作用,在硬币金属复合体的结构和发光中起着至关重要的作用.
- 16组元素 (基) 可以充当桥梁连接体,影响金属集群的电子和光学特性.
研究的目的:
- 合成和描述一系列新的同结构金银复合体.
- 研究不同16组原子 (O,S,Se) 对这些复合物的发光特性的影响.
- 探索黄金 (I) 氧系统及其类型的结构和光物理特性.
主要方法:
- 使用像X射线晶体学这样的技术合成和描述金银复合体.
- 光发光光谱学用于研究辐射特性 (能量,寿命).
- 可变温度研究 (冷玻璃测量) 来探测激发状态.
主要成果:
- 成功合成了同结构的[Au3(mu3-E) Ag(PPh2py)3](BF4) 2复合体,其中E=O,S,Se.
- 观察到排放能量的显著变化 (蓝色到色) 与桥梁石化原子 (O到Se) 的变化.
- 报告了第一个黄金光系统 (E=O) 的第一个发光.
- 结构特征揭示了一个Au3Ag四面体核心,在固态中没有支持的气友性相互作用.
- 发光寿命测量表明E=S和E=Se系统中激发状态的旋转禁止性质.
- 冷玻璃的测量表明,这些系统的能量排放状态更高.
结论:
- 这些金银星团的发射能量可以通过改变桥梁石化原子来调整,从而实现颜色调整.
- 发光特性归因于联体到金属到联体电荷转移 (LMMCT) 或以金属为中心的集群为基础的转换.
- 这些发现为设计基于多核金银复合体的新型发光材料提供了基础.
相关概念视频
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