Ballistic energy transport in molecules

化学系化学结构、动力学和机制（CSDM-A）项目将资助杜兰大学的Igor Rubtsov教授和Alexander Burin教授研究分子中能量的异常快速运动，即所谓的“弹道能量传输”。大多数情况下，能量（以热的形式）以热扩散的形式在材料中缓慢地传递。Rubtsov教授的研究小组已经发现了一种系统，在这种系统中，储存在长分子中的能量可以迅速转移到遥远的地方。这种异常的能量转移可能有助于科学家发现具有更好热性能的新材料。参与该项目的研究生和本科生将接受激光和光学科学方面的培训。PI和共同PI参与了校园内的许多教育活动，包括杜兰大学LSAMP暑期本科生研究培训计划，该计划为来自科学领域代表性不足的群体的本科生提供真实的研究经验。Igor Rubtsov教授和Alexander Burin教授及其各自的研究小组将把超快激光光谱（弛化辅助二维红外光谱）与理论建模相结合，以更好地理解在分子显著距离上的快速能量传输是如何发生的。这些科学家希望回答的一些问题包括：(1)决定弹道运输速度和效率的主要因素是什么？温度如何影响弹道传输的速度？材料的三维结构如何影响弹道传输的速度？影响输运的因素包括一级链和二级链结构、链结构、源振动模式的性质和能量以及温度。这些研究将有助于建立最可能的输运机制，因此可能会提出减少弹道能量输运损失的方法。弹道输运机制可能不得不被认为是分子中能量输运的主要组成部分，特别是对于具有重复单元的官能团的分子，这是非常常见的。因此，这项研究有可能在非常基础的水平上开发理解分子振动能量传递的新方法，并可能对物理和材料科学与工程产生广泛的影响。

With this award, the Chemical Structure, Dynamics and Mechanisms (CSDM-A) Program in the Division of Chemistry is funding Professors Igor Rubtsov and Alexander Burin of Tulane University to investigate unusually rapid movement of energy in molecules, so-called "ballistic energy transport." Most often energy (as heat) is transported slowly through materials as thermal diffusion. Professor Rubtsov's research group has discovered systems where energy deposited in long molecules is rapidly transferred to distant locations. This anomalous transfer of energy may help scientists discover new materials with improved thermal properties. The graduate and undergraduate students working on this project will receive training in laser and optical science. The PI and co-PI participate in a number of educational activities on their campus, including the Tulane LSAMP Summer Undergraduate Research Training Program, which provides undergraduates students from groups underrepresented in science with authentic research experiences.Professors Igor Rubtsov and Alexander Burin and their respective research groups will combine ultrafast laser spectroscopy (relaxation-assisted two-dimensional infrared spectroscopy) combined with theoretical modeling to develop a better understanding of how the very rapid energy transport over molecularly-significant distances occurs. Some of the questions that these scientists hope to answer include: (1) What are the main factors determining the speed and efficiency of ballistic transport? How does temperature effect the speed of ballistic transport? How does the three dimensional structure of a material effect the speed of ballistic transport? Among the factors affecting transport to be examined are the primary and secondary chain structure, chain architecture, the nature and energy of the source vibrational mode, and the temperature. These studies will help to establish the most likely transport mechanisms and,as such, will likely suggest ways of reducing losses for ballistic energy transport. The ballistic transport mechanism may have to be considered as a principal component of energy transport in molecules, especially for molecules featuring functional groups with repeating units, which are very common. Thus, this study has the potential of developing new ways of understanding vibrational energy transport in molecules at a very fundamental level and may have a broad impact on physical and materials science and engineering.