富拉米德线程的多态光诱导放松和光异构能力:一项计算和实验研究
Piero Altoè1, Natalia Haraszkiewicz, Francesco G Gatti
1Dipartimento di Chimica "G.Ciamician", Universita di Bologna, via Selmi 2, 40126 Bologna, Italy.
Journal of the American Chemical Society
|December 17, 2008
概括
胺酸通过复杂的失活路径经历超快速的衰变和光异构. 非平衡动力学和旋转轨道合控制着它们在可光控制的罗塔克桑中的光化学反应性和效率.
科学领域:
- 摄影化学的使用.
- 超分子化学 超分子化学
- 计算化学计算化学
背景情况:
- 氨酸和氨酸胺是可光控制的轮素中关键的光活性成分.
- 这些分子使环穿通过cis-trans光异构化.
研究的目的:
- 调查fumaramides中的超快衰变和光诱导异构化.
- 描述关闭通道和光化学机制的特征.
主要方法:
- 使用CASPT2//CASSCF计算方法对隔离的烟胺.
- 采用时间分辨率的光谱技术,用于溶解替代的烟胺.
主要成果:
- 确定了复杂的竞争性停机道网络,包括内部转换和系统间交叉 (ISC).
- 在单元和三元状态中观察到皮秒衰变和光化学/光物理特性.
- 证明单点光化学遵循非卡沙规则模型,由不平衡动力学驱动.
- 由于单点/三点状态退化和旋转轨道合,在皮秒时间尺度上发现了超快的ISC过程,增强了光异体化.
结论:
- 这项研究阐明了复杂的失活路径,这些路径控制着富拉米德的光化学反应.
- 非平衡动力学和旋转轨道合对于控制光化学反应性和效率至关重要.
- 这一理解为设计和控制基于胺的可光控制系统提供了原则.
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