Development of Algorithms for DFT Calculations of the Rate of Transitions In Ground and Excited States

基态和激发态跃迁速率 DFT 计算算法的开发

• 批准号: 0111468
• 负责人: Hannes Jonsson
• 金额: $ 31.8万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0111468&HistoricalAwards=false
• 关键词: Development; Algorithms; DFT; Calculations; Rate

Hannes Jonsson of the University of Washington is supported by the Theoretical and Computational Chemistry Program to develop methods for calculating transition rates in materials in combination with a plane-wave-based density functional theory (DFT) description of the energetics. Methods for finding mechanisms and transmission rates, such as the dimer method, climbing image-nudged elastic band method, and optimal hyperplanar transition state theory, will be explored and implemented. Methodologies will be applied to study diffusion and growth in semiconductors, in particular the growth of silicon/germanium surface mounds that may be useful in opto-electronic applications. Simulations that combine DFT estimates of transmission rates and kinetic Monte Carlo simulations of long time dynamics will be carried out to enable careful comparisons to new experimental data. This project will also begin developing techniques to calculate excited states in condensed matter. A many-body perturbation expansion that builds in corrections to the DFT mean field description will be tested on small molecules, and then applied to study optical properties and photoinduced catalysis on titanium dioxide surfaces. The first principles prediction of technologically important material properties is a longstanding goal. The combination of efficient theoretical chemistry techniques and implementation on computer clusters or parallel computers finally can bring this elusive goal within reach. The outcomes of this research are anticipated to contribute to new knowledge of quantum dots, which have technological promise for use as optical switches. As well, studies of titanium dioxide photocatalysis are expected to improve understanding of important applications for this material that include harmful microorganism destruction, cancer cell inactivation, and oil spill cleanup.

华盛顿大学的 Hannes Jonsson 在理论和计算化学项目的支持下，开发了结合基于平面波的密度泛函理论 (DFT) 能量学描述来计算材料转变率的方法。 将探索和实施寻找机制和传输速率的方法，例如二聚体方法、攀爬图像推动弹性带方法和最佳超平面过渡态理论。 方法将用于研究半导体的扩散和生长，特别是可能在光电应用中有用的硅/锗表面丘的生长。 将进行结合传输速率的 DFT 估计和长时间动态的动力学蒙特卡罗模拟的模拟，以便能够与新的实验数据进行仔细比较。 该项目还将开始开发计算凝聚态物质激发态的技术。 将在小分子上测试对 DFT 平均场描述进行修正的多体微扰展开，然后应用于研究二氧化钛表面的光学特性和光诱导催化作用。 对技术上重要的材料特性进行第一性原理预测是一个长期目标。 有效的理论化学技术与计算机集群或并行计算机上的实现相结合，最终可以使这一难以实现的目标触手可及。 这项研究的成果预计将有助于增进量子点的新知识，量子点具有用作光开关的技术前景。 此外，二氧化钛光催化的研究有望提高人们对这种材料重要应用的理解，包括破坏有害微生物、灭活癌细胞和清理溢油。