在光色硫氧化物复合物的兴奋状态扭曲
Beth Anne McClure1, Eric R Abrams, Jeffrey J Rack
1Department of Chemistry and Biochemistry, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701, USA.
Journal of the American Chemical Society
|March 31, 2010
概括
光色硫氧化物复合物在S-结合和O-结合状态之间经历光触发异构. 这种可逆的过程,受到硫替代物的影响,通过一种非抗性机制发生,具有不同的量子产量和时间尺度.
科学领域:
- 协调化学 协调化学
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
背景情况:
- 光色材料在暴露于光线时呈现可逆的颜色变化.
- 复合物以其多样化的光物理性质而闻名.
- 硫氧化配体提供独特的协调模式和反应性.
研究的目的:
- 为了合成和表征新的光色硫氧化复合物.
- 调查这些复合体中光诱导异构化的机制.
- 探索替代电子效应对光色行为的影响.
主要方法:
- (II) 复合物的合成和特征与二甲和硫氧化物联体.
- 紫外线-Vis吸收和发射光谱用于研究电子过渡.
- 五秒短暂吸收光谱检测激发状态动态.
- 电化学测量以评估氧化还原特性.
主要成果:
- 成功合成了具有不同硫氧化配体 (OSOBn,OSONap,OSOBnF) 的[Ru(bpy) ((2) ((OSOR) ] ((+) 复合物.
- 在电荷转移激发时,从S键到O键的硫氧化物协调证明了光触发的异构化.
- 在甲醇中观察到可逆的异构化,并与S键异构体的热逆转.
- 确定量子产量 (Phi(s-->o)) 和异构化时间常数 (tau(s-->o)) 受硫替代物的影响.
- 光谱数据表明,地面和兴奋状态之间存在显著的扭曲,涉及到特定的振动模式.
结论:
- 合成的硫氧化复合体表现出高效的光色.
- 异构化通过一个非adiabatic机制从放松的 (3) MLCT状态进行.
- 对硫的替代作用调节了与S结合的同位素的特性.
- 低频振动模式在异构化途径中起着至关重要的作用.
相关概念视频
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