The Dynamics of Phase Changes in Molecular Clusters

分子簇相变动力学

• 批准号: 9302157
• 负责人: Lawrence Bartell
• 金额: $ 47.5万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-01 至 1996-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9302157&HistoricalAwards=false
• 关键词: Dynamics; Phase; Changes; Molecular; Clusters

In this project in the Experimental Physical Chemistry Program of the Chemistry Division, Bartell will study the dynamics of homogeneous nucleation in phase changes in which he will use two new techniques which are relevant to studying solid-state transformations. Experimentally he will probe clusters generated in a supersonic flow using electron diffraction at various times-of-flight to monitor changes in packing during molecular "phase transitions." He will also characterize the molecular behavior computationally using molecular dynamics simulations. The formation of "critical nuclei" will be revealed by the simulations. Many of the same phase transitions will be studied using both techniques. %%% Studies of nucleation, such as the changes from one phase to another in solid- or liquid-state matter, are of crucial importance in many areas of science and technology, such as meteorology, materials engineering, petroleum catalysis, and earth sciences. This research program aims at acquiring a better understanding of such homogeneous phase changes by examining the different ways that molecules are packed in arrays. A special emphasis of this program is a comparison of theoretical prediction and experimental measurement of the rate of phase transitions. New tests of nucleation theory will be made, resulting in insights into the molecular mechanisms of phase changes.

在这个实验物理化学项目中， 化学部，巴特尔将研究的动力学 在相变中，他将使用 两种新的技术，这是有关研究固态 转变 在实验上，他将探测星系团 利用电子衍射在超音速流中产生的. 不同的飞行时间，以监测包装的变化， 分子“相变。“他还将描述 用分子动力学计算分子行为 模拟 “临界核”的形成将是 通过模拟显示。 许多同相 将使用这两种技术研究过渡。 %%% 成核的研究，例如从一个相到 另一种是固态或液态物质， 在许多科学和技术领域的重要性，如 气象学，材料工程，石油催化， 地球科学 该研究计划旨在获得 更好地理解这种均匀的相变， 研究分子的不同排列方式 阵 本计划的一个特别重点是比较 速率的理论预测和实验测量 的相变。 成核理论的新测试将是 的分子机制，从而深入了解 阶段变化。