Toward the Coherent Control of Large Amplitude Molecular Dynamics

走向大振幅分子动力学的相干控制

• 批准号: 1214123
• 负责人: Geoffrey Blake
• 金额: $ 42.8万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1214123&HistoricalAwards=false
• 关键词: Toward; Coherent; Control; Large; Amplitude

In this project, funded by the Chemical Structure, Dynamics and Mechanisms Program of the Chemistry Division, Prof. Geoffrey Blake of the California Institute of Technology will conduct a research program that seeks to coherently control the large amplitude molecular dynamics in isolated molecules and hydrogen bonded clusters using sub-picosecond Terahertz (THz) pulses. Specifically, intense (up to MV/cm) THz electric fields will be generated by tilted pulse front generation in lithium niobate crystals and/or plasma filamentation in gaseous media in order to pump the softest intramolecular and intermolecular modes in target systems to high degrees of excitation. The resulting state distributions and internal dynamics will be probed, with complete eigenstate resolution, by chirped pulse-Fourier Transform MicroWave spectroscopy. The first targets are small prebiotic molecules that also serve as molecular models of hydrogen bonding interactions pivotal to the structure and activities of biopolymers, along with hydrogen bonded clusters that illuminate the fundamental interactions that govern the formation of aqueous aerosols in the atmosphere. The pump-probe spectra and time-resolved dynamics will provide the transformational tools that are needed for observations with the next generation of microwave to THz telescopes such as the Atacama Large Millimeter Array, in the exploration of the complex potential energy surfaces of liquids and bioplymers, and in the development of coherent control strategies for the large amplitude motion that operate in even the simplest building blocks of hydrogen bonded assemblies. This research uses new light source and detection technology that allows the weak but very important interactions between hydrogen bonded molecules to be observed with unprecedented resolution. Understanding these interactions is important in many fields; this work focuses on interactions in small prebiotic molecules that are monitored in space and water clusters that are important to understanding the formation and fate of aerosol particles in the atmosphere. This project will be conducted with the assistance of graduate and undergraduate students, including women and members of underrepresented minorities. In addition to these activities, the group headed by Prof. Blake is strongly involved in the Caltech K-12 educational/outreach programs, and is developing new teaching modules in spectroscopy for hands-on science curricula in local classrooms. The support provided here will also make it possible to develop low-cost laboratory instruments and experiments for inquiry-based undergraduate instruction that highlights the strong ties between molecular dynamics and spectroscopy.

在该项目中，由化学部的化学结构，动力学和机制计划资助，加州理工学院的Geoffrey Blake教授将进行一项研究计划，旨在利用亚皮秒太赫兹（THz）脉冲相干控制孤立分子和氢键团簇中的大振幅分子动力学。具体地，强（高达MV/cm）THz电场将通过在锂酸盐晶体中的倾斜脉冲前沿生成和/或在气态介质中的等离子体激发来生成，以便将目标系统中最软的分子内和分子间模式泵送到高度激发。 由此产生的状态分布和内部动力学将探测，与完整的本征态分辨率，啁啾脉冲傅里叶变换微波光谱。第一个目标是小的益生元分子，也作为分子模型的氢键相互作用的关键的结构和活动的生物聚合物，沿着的氢键簇，照亮了基本的相互作用，在大气中形成的水性气溶胶。泵浦-探测光谱和时间分辨动力学将为使用下一代微波到太赫兹望远镜（如阿塔卡马大型毫米波阵列）进行观测提供所需的转换工具，以探索液体和生物分子的复杂势能表面，并在发展相干控制策略的大幅度运动，甚至在最简单的氢键的构建块操作，组件.这项研究使用了新的光源和检测技术，可以以前所未有的分辨率观察氢键分子之间微弱但非常重要的相互作用。 了解这些相互作用在许多领域都很重要;这项工作的重点是在空间和水集群中监测的小益生元分子的相互作用，这对了解大气中气溶胶颗粒的形成和命运很重要。 该项目将在研究生和本科生，包括妇女和代表性不足的少数民族成员的协助下进行。除了这些活动外，由Blake教授领导的小组还积极参与加州理工学院K-12教育/推广计划，并正在为当地教室的实践科学课程开发新的光谱学教学模块。这里提供的支持也将使开发低成本的实验室仪器和实验成为可能，以探究为基础的本科教学，突出分子动力学和光谱学之间的紧密联系。