Mapping Atomic Motions with Ultrabright Electrons: Fundamental Space-Time Limits to Imaging Chemistry

用超亮电子绘制原子运动：成像化学的基本时空限制

• 批准号: RGPIN-2019-06518
• 负责人: Miller, RJDwayne
• 金额: $ 6.85万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=716183
• 关键词: Mapping; Atomic; Motions; Ultrabright; Electrons

The PI is transitioning back from the Max Planck Institute in Germany (he co-founded) to the University of Toronto. The requested funds will enable continuation of this research program with a focus on atomically resolved dynamics. This research program is part of a 10-year effort to meet some of the grand challenges in science, notably to directly image chemistry and biology at fundamental space-time limits. This program exploits the ultrabright electron source technology developed by the PI's group to literally light up atomic motions in real time. The major challenge is to push this imaging technology to the single molecule limit to observe single molecule trajectories at the atomic level. This objective is now in reach. This research program has achieved some of the dream experiments in chemistry: 1) obtaining the first molecular movies of structural transitions, 2) first full atomically resolved movie of electrocyclization with conserved stereochemistry (bond formation), 3) electron transfer in organic and organometallic systems, 4) the classic I3 problem and effect of the lattice in directing chemistry, 5) and the first full atomic resolved chemical reaction (via solving the phase problem in image reconstruction), which achieved the fundamental limits in space-time imaging chemistry. In terms of impact on the field of chemistry, the very first atomic movies illustrated that the numerous number of possible nuclear motions leading to changes in molecular structure, also known as chemistry, collapse to just a few key reaction modes. It is this enormous reduction in dimensionality that occurs in the barrier crossing region that makes chemistry transferable (re: the empirical discovery of named reactions). This work has led to a new conceptual basis for chemistry based on reaction modes that unifies structure and dynamics to help better predict the nuclear configurations of the barrier crossing region and thereby better control chemistry. The concept of reaction modes (reduced dimensionality) is found to scale in complexity to the level of biological molecules. With recent advances in electron sources, detectors, and nanofluidic devices, the PI's group is closing in on obtaining atomic resolution to single molecular trajectories atomic real space imaging of bio-molecules in action. The ultimate objective of this program is to connect molecular structure-function relationships revealed in these studies to close the loop between chemistry and biology.

PI正在从德国的Max Planck Institute（他共同创立）过渡到多伦多大学。 要求的资金将使该研究计划继续进行，重点是原子解决动态。该研究计划是为满足科学方面的一些巨大挑战的十年努力的一部分，尤其是在基本时空限制下直接对化学和生物学进行图像。该程序利用了PI小组开发的Ultrabright电子源技术，以实时点亮原子动作。 主要的挑战是将这种成像技术推向单分子极限，以观察原子水平的单分子轨迹。这个目标现在已达到。 该研究计划已经实现了化学方面的一些梦想实验：1）获得结构过渡的第一部分子电影，2）首次完整的全原子解决电影的电囊性电影，具有保守的立体化学（键形成）（键形成），3）在有机和有机金属系统中的电子传递，4）经典的I3问题和求解，并通过固定在求解中，并通过溶解度（第5）效应（5），以及第5次反应（5）。图像重建中的相位问题），这实现了时空成像化学的基本限制。在对化学领域的影响方面，第一部原子电影说明，导致分子结构变化的大量可能的核运动（也称为化学）仅崩溃，仅为几种关键的反应模式。 正是在障碍物越过区域中发生的巨大降低使化学可转移（回复：命名反应的经验发现）。这项工作为基于反应模式而统一结构和动力学的反应模式为化学构成了新的概念基础，以帮助更好地预测屏障越过区域的核配置，从而更好地控制化学。 发现反应模式的概念（减少维度）的复杂性扩展到生物分子的水平。随着电子源，检测器和纳米流体设备的最新进展，PI组正在关闭，以获取对单个分子轨迹的原子分辨率原子真实空间成像的作用。 该程序的最终目标是将这些研究中揭示的分子结构 - 功能关系连接起来，以关闭化学和生物学之间的循环。