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.

在化学理论，模型和计算方法的支持下，普渡大学的亚当·瓦斯瑟曼教授正在开发高级理论和方法，用于计算计算机模拟分子和材料的电子结构，具有新的能力，以实现这些系统的实验的性能和解释。此外，分子碎片的密度功能理论的新方法旨在为不断增长的复杂性系统提供计算有效性。 Wasserman博士及其研究小组将着重于提高这些方法对“强相关类型”的挑战系统的准确性和效率。基于Kohn-Sham密度功能理论，这些系统占主导地位的这些系统通常无法达到标准近似值，这是使用最广泛使用的电子结构方法。除了拟议的研究工作所产生的更广泛的影响外，PI在拉丁美洲学生社区中的领导才能继续。其他教育活动包括由PI共同组织的两年一次的学校和研讨会以及PI将继续组织的“科学与社会进步”课程。在此奖项之后，Wasserman Research小组将重点关注两个主要的障碍：（1）对系统（DFT）的准确性（DFT）的准确性（dft）的准确性，即涉及到近距离范围 - 达到范围 - 涉及到范围 - 涉及到范围，即涉及到范围，即涉及到范围，这是相关的范围。 （2）提高此类计算的效率。通过开发最近的密度反向反转技术，该分离是可能的，该技术允许计算数值确切的非添加性非互动动能。为了实现第一个目标，Wasserman和他的小组将采用碎片密度的重叠功能来构建和测试以物理动机的近似值，以进行碎片之间的交换交换与相关能量功能。为了实现第二种，将遵循两管沟的方法，在该方法中，（a）将基于非加性动力学能量功能的确切约束来开发半局部片段密度功能； （b）训练有素的神经元网络将用于将非本地效应纳入全非相互作用的动力学能量函数中的元源化梯度近似（GGA）函数。所有进步都将通过开源守则嵌入计算，向更广泛的科学界提供。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，通过评估被认为是珍贵的支持。