Nonstatistical Dynamics of Reactive Intermediates

有了这个更新奖，有机和高分子化学计划继续支持康奈尔大学化学系教授巴里卡彭特的工作。 该研究将扩展PI在有机反应中的非统计动力学研究。由于卡彭特教授的工作，人们最近认识到，有机化学中的许多活性中间体都是通过选择性地激发它们的振动模式而形成的。 如果这些中间体继续生成产物的速度快于它们经历振动能重新分配的速度，则反应并不总是沿着最低能量路径进行，并导致意外的产物。在这个提议中，将进行旨在合成和研究可能导致额外的活性中间体的分子的实验，其中能量以非统计方式分布。 这项工作的一个主要重点是将现代计算化学与复杂的实验相结合，将研究那些处于深层能量极小值的中间体以及非统计动力学对其反应性的作用。 该项目的第二个主题是扩大反应的范围，其中可以探讨非统计动态问题。首先，这些影响已被提出热产生的单线双自由基。在新的工作中，这些想法将扩展到光化学，卡宾化学和化学活化稳定分子的化学。该项目的总体目标是更新化学动力学模型，以考虑动态效应。由于化学动力学在生物学、大气和环境化学、燃烧以及各种其他领域中起着至关重要的作用，因此预计提高动力学模型的准确性将产生广泛的影响。此外，学生将作为本研究的参与者接受的高度跨学科的培训将有助于提供现代科学研究现在需要的专业知识。

With this renewal award, the Organic and Macromolecular Chemistry Program continues its support of the work of Professor Barry Carpenter of the Department of Chemistry at Cornell University. The research will extend the PI's studies of nonstatistical dynamics in organic reactions. Largely as a result of Professor Carpenter's work it has recently been recognized that many reactive intermediates in organic chemistry are formed with selective excitation of their available vibrational modes. If these intermediates go on to products faster than they undergo vibrational energy redistribution, the reaction does not always follow the lowest energy path and leads to unexpected products. In this proposal, experiments designed to synthesize and investigate molecules that may lead to additional reactive intermediates in which the energy is distributed in a nonstatistical manner will be carried out. One principal focus of the work, which combines modern computational chemistry with sophisticated experiments, will be on those intermediates lying in deep energy minima and the role of nonstatistical dynamics on their reactivity. A second theme of the project is to broaden the range of reactions in which issues of nonstatistical dynamics can be explored. Primarily, these effects have been proposed for thermally generated singlet biradicals. In the new work, the ideas will be extended to photochemistry, to carbene chemistry, and to the chemistry of chemically activated stable molecules.A general goal of the project is to update models of chemical kinetics to take account of dynamic effects. Since chemical kinetics plays vital roles in biology, atmospheric and environmental chemistry, combustion, and in a variety of other domains, improving the accuracy of kinetic models is expected to have wide-ranging impact. In addition, the highly interdisciplinary training that students will receive as participants in this research will help provide the expertise that modern scientific research now demands.