Density Functional Theory of Molecular Fragments: Strong Electron Correlation Beyond Density Functional Approximations

分子片段的密度泛函理论：超越密度泛函近似的强电子相关性

• 批准号: 2306011
• 负责人: Adam Wasserman
• 金额: $ 53万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-15 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2306011&HistoricalAwards=false
• 关键词: Density; Functional; Theory; Molecular; Fragments

With support from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry, Professor Adam Wasserman of Purdue University is developing advanced theories and methods for computer simulation of the electronic structure of molecules and materials with new capabilities to enable highly accurate prediction of properties and interpretation of experiment for these systems. In addition, the new method of density functional theory of molecular fragments aims to provide computational efficiency for systems of ever-increasing complexity. Dr. Wasserman and his research group will focus on improving both the accuracy and the efficiency of these methods for the challenging systems of the “strongly-correlated type.” These systems in which electron correlation effects dominate, are typically out of reach for standard approximations based on Kohn-Sham Density Functional Theory, the most widely used electronic structure method. In addition to the broader impact resulting from the proposed research efforts, the PI's leadership within the Latin-American community of Purdue students will continue. Other educational activities include a bi-annual School and Workshop on Time-dependent DFT co-organized by the PI and a study-abroad course on “Science and social progress” that the PI will continue organizing.Under this award, the Wasserman research group will focus on two major thrusts: (1) Improving the accuracy of density-functional theory (DFT) calculations for systems that lie beyond the reach of state-of-the-art density-functional approximations; and (2) Improving the efficiency of such calculations. This separation is made possible by the development of recent density-to-potential inversion techniques that allow for the calculation of numerically exact non-additive noninteracting kinetic energies. To achieve the first goal, Wasserman and his group will employ an overlap functional of the fragment densities to construct and test physically motivated approximations for the inter-fragment exchange-correlation energy functional. To achieve the second, a two-pronged approach will be followed in which (a) a semi-local fragment-density functional will be developed based on exact constraints for the non-additive kinetic-energy functional; and (b) a trained neural network will be used to incorporate non-local effects into a meta-generalized gradient approximation (GGA) functional for the full noninteracting kinetic energy functional. All advances will be made available to the broader scientific community through open-source codes for density embedding calculations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学系化学理论、模型和计算方法项目的支持下，普渡大学的 Adam Wasserman 教授正在开发先进的理论和方法，用于分子和材料电子结构的计算机模拟，并具有新的功能，以实现高度准确的预测此外，分子片段密度泛函理论的新方法旨在为日益复杂的系统提供计算效率。 Wasserman 博士和他的研究小组将致力于提高准确性和准确性。的效率这些方法适用于具有挑战性的“强相关类型”系统。这些系统中电子相关效应占主导地位，通常无法达到基于 Kohn-Sham 密度泛函理论（最广泛使用的电子结构方法）的标准近似。除了拟议的研究工作产生的更广泛影响之外，PI 将继续在拉丁美洲普渡大学学生社区中发挥领导作用。其他教育活动包括由 PI 共同组织的两年一次的时间相关 DFT 学校和研讨会。以及PI将继续组织的“科学与社会进步”出国留学课程。在该奖项下，Wasserman研究小组将重点关注两大重点：（1）提高密度泛函理论（DFT）计算的准确性对于超出最先进的密度泛函近似范围的系统；以及（2）通过最近的密度-电势反演技术的发展，提高了这种计算的效率。允许计算数值精确的非加性非相互作用动能为了实现第一个目标，沃瑟曼和他的团队将采用碎片密度的重叠函数来构建和测试碎片间交换相关能量泛函的物理驱动近似。为了实现第二个目标，将采用双管齐下的方法，其中（a）将基于非加性动能的精确约束来开发半局部碎片密度泛函。 (b) 将使用训练有素的神经网络将非局部效应纳入元广义梯度近似 (GGA) 函数中，以实现完整的非相互作用动能函数。用于密度嵌入计算的开源代码。该奖项反映了 NSF 的法定使命，并且通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。