CAREER: Modeling Metal-Metal Oxide Interactions Using Spherosiloxane Adsorption on Single Crystal Metal Surfaces

结合从头算计算化学和实验光谱学来解决工程问题正成为一种日益广泛的方法。这个职业项目将强调理论和实验的结合，既可以进行基础研究，也可以培养具有不同经验水平的学生。研究部分侧重于开发一种新的模型系统，该系统将能够详细研究金属-绝缘体界面的化学和物理。这些界面对于包括微电子工程、多相催化和化学传感在内的一系列应用都很重要，但由于它们通常“埋藏”在连续的固体层下，因此很难用实验或理论进行研究。在这个项目中，将通过在催化金属单晶表面上吸附二氧化硅球状硅氧烷簇来形成实验和理论技术均可访问的模型界面。一系列实验技术将用于表征球硅氧烷的吸附和反应，改变金属衬底的组成和形态以及球硅氧烷簇的大小。第一性原理计算的结果将用于解释实验观察，帮助理解形成的界面的分子水平结构。一旦表征，模型界面将用于研究一个重要应用的机制：利用金属氧化物半导体器件检测H2气体。参与这项研究的研究生和本科生团队将在理论原理、先进的光谱技术和实际应用方面获得广泛的经验。这种理论、光谱技术和应用开发的协同作用也将在教学活动中得到强调。在这些努力中，我们将利用计算化学软件的效用来帮助学生在分子尺度上可视化化学反应。一门新的研究生/高级本科课程将侧重于从分子尺度转化的角度分析化学反应过程，学生使用计算化学软件是课程的关键组成部分。在本科课程中，分子模型模拟也将被引入到更基础的层面，在那里，它们将提供一种分析热力学和反应动力学的方法，以及一种有效的可视化反应过程的演示工具。这些示范也将用于向地区高中推广，强调基本的化学概念，同时使年轻学生接触到利用计算机技术的一个重要的、不断发展的研究领域。最后，这个职业规划要求开发一个网络模块，为计算化学概念提供简单的解释和示例；这个网站将对研究生、本科生和高中生开放。网络模块将是实现该项目所有教育目标的基本工具，包括与研究生、本科生和高中生相关的目标。因此，这些活动的总体影响将是开发一种结合实验/理论的方法来解决特定的工程问题-金属- sio2界面的化学性质-以及鼓励学生使用这种协同方法来处理一般工程问题的教育工具。

The combined use of ab initio computational chemistry and experimental spectroscopies in addressing engineering problems is becoming an increasingly widespread approach. This CAREER project will emphasize the combination of theory and experiment both in performing fundamental research and in educating students with diverse levels of experience. The research component focuses on development of a new model system that will enable detailed investigations of the chemistry and physics of metal-insulator interfaces. These interfaces are important for an array of applications, including microelectronics engineering, heterogeneous catalysis, and chemical sensing, but have been difficult to study using experiment or theory because they are typically "buried" under a continuous solid layer. In this project, model interfaces that are accessible to both experimental and theoretical techniques will be formed by adsorption of SiO2-like spherosiloxane clusters onto catalytic metal single crystal surfaces. A battery of experimental techniques will be used to characterize the adsorption and reaction of spherosiloxanes, varying the composition and morphology of the metal substrate along with the size of the spherosiloxane clusters. Results from first-principles computations will be used in interpreting experimental observations, helping to understand the molecular-level structure of the interfaces formed. Once characterized, the model interface will be used to study the mechanism for an important application: the detection of H2 gas using metal-oxide-semiconductor devices. Teams of graduate and undergraduate students who participate in this research will gain broad experience in theoretical principles, advanced spectroscopic techniques, and real-world applications.This synergy of theory, spectroscopic techniques, and application development will be emphasized in instructional activities as well. In these efforts, we will exploit the utility of computational chemistry software for aiding students in visualization of chemical reactions at the molecular scale. A new graduate/advanced undergraduate course will focus on analysis of chemical reaction processes in terms of molecular-scale transformations, with students' use of computational chemistry software representing a key component of the course. Molecular modeling simulations will also be introduced on a more basic level in undergraduate courses, where they will provide both a method for analysis of thermodynamics and reaction kinetics and an effective demonstration tool for visualization of reaction processes. These demonstrations will also be used in outreach to area high schools, emphasizing elementary chemistry concepts while at the same time exposing young students to an important, growing area of research that makes use of computer technology. Finally, this career plan calls for development of a web module that provides simple explanations and examples for computational chemistry concepts; this web site will be accessible to graduate, undergraduate, and high school students. The web module will be an essential tool in achieving all the educational goals of this project, including those relevant for graduate, undergraduate, and high school students. Thus, the overall impact of these activities will be the development of both a combined experimental/theoretical approach to a specific engineering problem-the chemistry of metal-SiO2 interfaces-and educational tools that will encourage students to use this synergistic approach in dealing with engineering problems in general.