AI 中文总结
该研究针对生物体系中目标生色团振动信号被基质掩盖的问题，介绍共振拉曼（RR）光谱的原理，并扩展出飞秒受激共振拉曼光谱（FSRRS），实现复杂体系中瞬态物种的分离。
AI 中文摘要
振动光谱可凭借化学键特异性报告分子结构，但在生物体系中，目标生色团的振动信号通常被周围基质的贡献掩盖。共振拉曼（RR）光谱通过将激发波长匹配到目标生色团的电子跃迁来解决该问题，这可使拉曼截面提升多达六个数量级，并将增强的模式限制在与共振电子态耦合的那些模式。本章介绍共振增强的物理基础，并展示RR如何在复杂生物体系中分离生色团特异性振动标记。随后，我们将相同原理扩展到时域，发展飞秒受激共振拉曼光谱（FSRRS）。在FSRRS中，拉曼泵浦被调谐到可见光范围，且可与选定激发态物种的瞬态吸收共振，这使得拉曼泵浦波长成为额外的实验变量。对激发态吸收流形上的该变量进行采样，提供了一种选择标准，可分离共享共同振动窗口的共存瞬态物种。
英文摘要
Vibrational spectroscopy reports on molecular structure with chemical-bond specificity, but in biological systems the vibrational signals of a target chromophore are typically buried under contributions from the surrounding matrix. Resonance Raman (RR) spectroscopy addresses this problem by matching the excitation wavelength to an electronic transition of the chromophore of interest, which increases Raman cross sections by up to six orders of magnitude and restricts the enhanced modes to those coupled to the resonant electronic state. This chapter introduces the physical basis of resonance enhancement and shows how RR isolates chromophore-specific vibrational markers in complex biological systems. We then extend the same principle into the time domain with femtosecond stimulated resonance Raman spectroscopy (FSRRS). In FSRRS, the Raman pump is tuned across the visible range and can be placed in resonance with the transient absorption of a chosen excited-state species, which makes the Raman pump wavelength an additional experimental variable. Sampling this variable across the excited-state absorption manifold provides a selection criterion that separates coexisting transient species sharing a common vibrational window.
