在超快光异型光谱学研究的树突结构模型中,在能量传输中产生一致的效应
Oleg P Varnavski1, Jacek C Ostrowski, Ludmila Sukhomlinova
1Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
Journal of the American Chemical Society
|February 21, 2002
概括
超快的光异性衰变被测量在分支的树突分子中. 在三元体系统中观察到一致的能量传输,与四元体中的不一致迁移不同.
科学领域:
- 光物理学的光学物理学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 丹地里默是分支的大分子,具有独特的特性.
- 了解树枝状体中的能量迁移对于它们的应用至关重要.
- 模型系统被用来研究树枝状物中的基本过程.
研究的目的:
- 在模型分支树突分子中研究超快光异性衰变.
- 区分不连贯和连贯的能源迁移机制.
- 分析分子对称性对能量传输的影响.
主要方法:
- 时间分辨率光异质性衰变测量.
- 模型树突分子的合成,具有C(3) 和T(d) 对称性.
- 使用现象学量子力学模型进行分析.
主要成果:
- 四面体 (T(d)) 系统在亚平秒时间尺度 (880 fs) 上显示了异构性衰变,这与不连贯的能量迁移相一致.
- 以为中心的三元体 (C(3) 系统的衰变时间要短得多 (35 fs).
- 三元体系统的快速衰变表明了一个连贯的染色体间能量传输机制.
结论:
- 分子对称性显著影响树突系统中的能量迁移机制.
- 在特定的分支架构中,一致的能量传输是一种可行的机制.
- 这项研究提供了对树枝状体基本光物理过程的洞察.
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