一个功能化的平面单层的定向动力学探测通过偏振选择角度的红外探测谱
Jun Nishida1, Chang Yan1, Michael D Fayer1
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|September 27, 2016
概括
我们开发了一种新的光谱技术, 这种方法揭示了功能化单层的局限的外平面和复杂的内平面定向动态.
科学领域:
- 表面科学
- 光谱学
- 物理化学
背景情况:
- 对于许多应用来说,了解表面的分子动力学至关重要.
- 在SiO2上的基单层是界面研究的模型系统.
- 金属碳酸头组提供独特的光谱手柄.
研究的目的:
- 开发和应用一种用于探测界面定向动态的新谱技术.
- 为了研究功能化单层的皮秒定向放松.
- 提取和分析外平面和内平面的方向相关函数.
主要方法:
- 开发了偏振选择角度的红外探测光谱.
- 结合时间平均红外线性二极化测量.
- 使用多个事件角度和最近开发的模型独立分析理论框架.
主要成果:
- 在单层-空气接口的标志性皮秒定向放松.
- 发现高度限制的外平面头组运动与双模角分布.
- 观察到重要的平面内运动,包括惯性,摇摆 (~3 ps) 和随机化 (~25 ps) 动态.
结论:
- 开发的光谱技术成功地探测了接口的复杂方向动态.
- 团表现出明显的外平面和内平面放松行为.
- 这些发现提供了对功能化单层分子运动的洞察力.
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