超快電子轉移反應中振動波包的相互作用
作者：
小柯機器人發布時間：2020/12/12 21:03:45
普林斯頓大學Gregory D. Scholes課題組揭示了超快電子轉移反應中振動波包的相互作用。 該項研究成果發表在2020年12月7日出版的《自然—化學》。
電子轉移反應促進了生物和化學中的能量傳遞和光催化過程。最近的研究表明，分子振動可以使某些電子轉移反應的劇烈加速，並通過抑制和增強反應路徑來控制它。
該文中，研究人員通過超快光譜實驗和量子動力學模擬實驗揭示了量子振動如何參與電子轉移反應。研究人員觀察到彈道電子轉移（~30fs）沿著由高頻促進振動組成的反應坐標系。由於電子轉移反應，當沿著另一個振動坐標系時系統突然失去平衡。這導致（通過電子轉移反應，而不是雷射脈衝）在與反應產物相關的模式下沿著第二個反應坐標產生新的振動相干。
這些結果解決了一個由多個振動坐標組成的複雜反應軌跡，該軌跡像一系列棘輪一樣，逐漸減少反應物狀態的重現。
附：英文原文
Title: Interplay of vibrational wavepackets during an ultrafast electron transfer reaction
Author: Shahnawaz Rafiq, Bo Fu, Bryan Kudisch, Gregory D. Scholes
Issue&Volume: 2020-12-07
Abstract: Electron transfer reactions facilitate energy transduction and photoredox processes in biology and chemistry. Recent findings show that molecular vibrations can enable the dramatic acceleration of some electron transfer reactions, and control it by suppressing and enhancing reaction paths. Here, we report ultrafast spectroscopy experiments and quantum dynamics simulations that resolve how quantum vibrations participate in an electron transfer reaction. We observe ballistic electron transfer (~30fs) along a reaction coordinate comprising high-frequency promoting vibrations. Along another vibrational coordinate, the system becomes impulsively out of equilibrium as a result of the electron transfer reaction. This leads to the generation (by the electron transfer reaction, not the laser pulse) of a new vibrational coherence along this second reaction coordinate in a mode associated with the reaction product. These results resolve a complex reaction trajectory composed of multiple vibrational coordinates that, like a sequence of ratchets, progressively diminish the recurrence of the reactant state.
DOI: 10.1038/s41557-020-00607-9
Source: https://www.nature.com/articles/s41557-020-00607-9