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QLC: EAGER: Toward the visualization of chemical control

QLC：EAGER：迈向化学控制的可视化

基本信息

批准号：
1836435
负责人：
Roseanne Sension
金额：
$ 25万
依托单位：
Regents of the University of Michigan - Ann Arbor
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-15 至 2022-01-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1836435&HistoricalAwards=false
关键词：
QLC EAGER Toward visualization chemical

项目摘要

In this project funded by the Chemical Structure Dynamics and Mechanism (CSDM-A) program of the Chemistry Division, Professor Roseanne Sension of The University of Michigan is using x-ray techniques to develop visual images and movies of the internal motions of the atoms in molecules which have been exposed to a pulse of ultraviolet (UV) or visible (Vis) light. Pulses of UV/Vis light can cause distortions of the chemical bonds in molecules, and even cause them to break or re-form in what we call a photochemical reaction. These light-induced motions occur on very short time scales, from a few femtoseconds to a few nanoseconds (A femtosecond is one quadrillionth of a second. A nanosecond is one billionth of a second). X-ray diffraction has been used to determine molecular structure for more than a century. However, these have been molecules that are stationary in a crystal lattice. In order to capture the extremely fast motions of molecules after they have been exposed to light, Prof. Sensions is using the intense x-rays produced by free electron lasers (for example, at the LINAC Coherent Light Source at Stanford University). Professor Sension and her students are measuring how molecules absorb x-rays, and developing methods to convert x-ray absorption information into images that can be sequenced as frames in a motion picture. The visualization of photochemical reactions at the molecular level helps us understand chemical reactions in general, and also supports the long-term goal to control chemical reactions with light. The project is also training students in the use of advanced experimental facilities and in advanced computer simulation of UV/Vis and x-ray absorption. In addition, the results are being integrated into the undergraduate curriculum to help students understand the relevance of mathematics and physics to chemistry.This project uses femtosecond x-ray free electron lasers to visualize quantum wave packet motion in molecules. A short laser pulse is used to initiate and control a photochemical reaction. A polarized x-ray pulse probes the coherent structural dynamics on the excited state potential energy surface. Cobalamin photochemistry and photophysics is used as a model system for molecular visualization and quantum control with femtosecond x-ray pulses sources. The visualization of coherent excited state dynamics and the correlation of dynamics with the molecular ligands facilitate the understanding and development of cobalamin based molecular devices. The experimental observations are interpreted using quantum chemical calculations and finite difference near edge spectroscopy ab initio code to simulate x-ray absorption spectra. In addition, general simulation methods are being developed to model ultrafast x-ray spectroscopy and coherent excited state dynamics. This research project has implications for a wide range of applications in energy conversion, medical therapeutics, molecular electronics, switches, sensors, and delivery platforms. Many of these applications exploit intrinsically quantum mechanical dynamics of the molecules involved.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在这个由化学部门化学结构动力学和机制（CSDM-A）项目资助的项目中，密歇根大学的Roseanne Sension教授正在使用x射线技术来开发暴露在紫外线（UV）或可见光（Vis）脉冲下的分子中原子内部运动的视觉图像和电影。紫外线/可见光脉冲会导致分子中的化学键扭曲，甚至导致它们断裂或重新形成，这就是我们所说的光化学反应。这些由光引起的运动发生在非常短的时间尺度上，从几飞秒到几纳秒（一飞秒是一千万亿分之一秒）。纳秒是十亿分之一秒)。一个多世纪以来，x射线衍射一直被用来确定分子结构。然而，这些都是固定在晶格中的分子。为了捕捉暴露在光线下的分子的极快运动，sensons教授正在使用自由电子激光器产生的强x射线（例如，在斯坦福大学的LINAC相干光源）。森森教授和她的学生们正在测量分子如何吸收x射线，并开发将x射线吸收信息转换成图像的方法，这些图像可以在电影中作为帧进行排序。光化学反应在分子水平上的可视化有助于我们理解化学反应，也支持用光控制化学反应的长期目标。该项目还训练学生使用先进的实验设施和先进的计算机模拟紫外线/可见和x射线吸收。此外，这些结果将被整合到本科课程中，以帮助学生理解数学和物理与化学的相关性。这个项目使用飞秒x射线自由电子激光器来可视化分子中的量子波包运动。使用短激光脉冲来启动和控制光化学反应。偏振x射线脉冲探测激发态势能面上的相干结构动力学。钴胺素光化学和光物理被用作飞秒x射线脉冲源分子可视化和量子控制的模型系统。相干激发态动力学的可视化和动力学与分子配体的相关性有助于钴胺素基分子器件的理解和发展。利用量子化学计算和有限差分近边光谱从头算代码对实验结果进行解释，模拟x射线吸收光谱。此外，超快x射线光谱学和相干激发态动力学的一般模拟方法也在开发中。该研究项目在能量转换、医学治疗、分子电子学、开关、传感器和输送平台等领域具有广泛的应用前景。这些应用中的许多都利用了所涉及分子的内在量子力学动力学。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Ultrafast XANES Monitors Femtosecond Sequential Structural Evolution in Photoexcited Coenzyme B 12

超快 XANES 监测光激发辅酶 B 12 中的飞秒顺序结构演化

DOI：
10.1021/acs.jpcb.9b09286
发表时间：
2019
期刊：
The Journal of Physical Chemistry B
影响因子：
0
作者：
Miller, Nicholas A.;Michocki, Lindsay B.;Konar, Arkaprabha;Alonso-Mori, Roberto;Deb, Aniruddha;Glownia, James M.;Sofferman, Danielle L.;Song, Sanghoon;Kozlowski, Pawel M.;Kubarych, Kevin J.
通讯作者：
Kubarych, Kevin J.

Probing the Excited State of Methylcobalamin Using Polarized Time-Resolved X-ray Absorption Spectroscopy

使用偏振时间分辨 X 射线吸收光谱法探测甲钴胺的激发态

DOI：
10.1021/acs.jpcb.9b05854
发表时间：
2019
期刊：
The Journal of Physical Chemistry B
影响因子：
0
作者：
Michocki, Lindsay B.;Miller, Nicholas A.;Alonso-Mori, Roberto;Britz, Alexander;Deb, Aniruddha;Glownia, James M.;Kaneshiro, April K.;Konar, Arkaprabha;Koralek, Jake;Meadows, Joseph H.
通讯作者：
Meadows, Joseph H.

Watching Excited State Dynamics with Optical and X-ray Probes: The Excited State Dynamics of Aquocobalamin and Hydroxocobalamin

使用光学和 X 射线探针观察激发态动力学：水钴胺和羟钴胺的激发态动力学

DOI：
10.1021/jacs.3c04099
发表时间：
2023
期刊：
Journal of the American Chemical Society
影响因子：
15
作者：
Sension, Roseanne J.;McClain, Taylor P.;Lamb, Ryan M.;Alonso-Mori, Roberto;Lima, Frederico Alves;Ardana-Lamas, Fernando;Biednov, Mykola;Chollet, Matthieu;Chung, Taewon;Deb, Aniruddha
通讯作者：
Deb, Aniruddha

Ultrafast Excited State Dynamics and Fluorescence from Vitamin B 12 and Organometallic [Co]–C≡C–R Cobalamins

维生素 B 12 和有机金属 [Co]–C–C–R 钴胺素的超快激发态动力学和荧光

DOI：
10.1021/acs.jpcb.0c04886
发表时间：
2020
期刊：
The Journal of Physical Chemistry B
影响因子：
0
作者：
Salerno, Elvin V.;Miller, Nicholas A.;Konar, Arkaprabha;Li, Yan;Kieninger, Christoph;Kräutler, Bernhard;Sension, Roseanne J.
通讯作者：
Sension, Roseanne J.

Visualizing ultrafast chemical dynamics with X-rays

用 X 射线可视化超快化学动力学