Accurate Nonempirical Density-Functional Methods with Applications

准确的非经验密度泛函方法及其应用

• 批准号: RGPIN-2015-04814
• 负责人: Staroverov, Viktor
• 金额: $ 5.39万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=632414
• 关键词: Accurate; Nonempirical; Density; Functional; Methods

Quantum chemistry is a highly specialized yet critically important branch of chemical research. The most visible outcomes of the work of quantum chemists are predictive mathematical models and computer programs which are used as tools by thousands of researchers in industry and academia to unravel the intricacies of chemical processes, predict physical properties of matter under normal and extreme conditions, design new materials, and search for molecules with target medicinal properties. Our group is one of those that develop such tools; we specialize in a particular quantum-mechanical technique called density-functional theory (DFT). Over the previous granting period, we have advanced an unconventional approach to DFT in which one directly approximates effective one-electron potentials rather than energy functionals. In the next five years, we will take the potential-based DFT to a new level of accuracy and utility by bridging it with nonempirical wavefunction methods. In particular, we will (1) develop conceptually new methods for constructing exchange-correlation potentials which will enable researchers to devise better density-functional and multiscale methods for use in computer simulations of materials; (2) employ our new tool called the average local electron energy to obtain a better understanding of the relation between chemical structure and properties; (3) explore a special reduced form of the Schrödinger equation to uncover fundamental connections between wavefunction methods and DFT; (4) devise a new density-functional approach for studying time-dependent many-electron phenomena; (5) test new ideas to overcome limitations of existing approximate functionals; (6) construct accurate density functionals from model potentials. Tangible outcomes of the proposed research will include new computational methods for investigation of reaction mechanisms, analysis of quantitative structure-activity relationships, and for applications in materials science, attosecond spectroscopy, and other fields. In terms of highly qualified personnel training, the research will form the basis for 10 graduate and 5 undergraduate theses and will contribute expertise to collaborations across interdisciplinary boundaries.

量子化学是化学研究中一个高度专业化但又极其重要的分支。量子化学家的工作最明显的成果是预测数学模型和计算机程序，数以千计的工业界和学术界的研究人员将其用作工具，以揭开复杂的化学过程，预测物质在正常和极端条件下的物理性质，设计新材料，并寻找具有目标药物特性的分子。我们的团队是开发这种工具的团队之一；我们专门研究一种特殊的量子力学技术，称为密度泛函理论(DFT)。在之前的授权期内，我们提出了一种非传统的密度泛函方法，即直接近似有效单电子势能，而不是能量泛函。在接下来的五年里，我们将通过将基于势的DFT与非经验波函数方法相结合，将其精度和实用性提升到一个新的水平。具体地说，我们将(1)从概念上开发构造交换相关势的新方法，这将使研究人员能够设计出更好的密度泛函和多尺度方法，用于材料的计算机模拟；(2)使用我们的新工具--平均局部电子能量，以更好地理解化学结构和性质之间的关系；(3)探索一种特殊的简化形式的薛定谔方程，以揭示波函数方法和DFT之间的基本联系；(4)设计一种新的密度泛函方法来研究依赖于时间的多电子现象；(5)测试新的想法，以克服现有近似泛函的局限性；(6)由模型势构造精确的密度泛函。拟议研究的具体成果将包括新的计算方法，用于研究反应机理，分析定量结构-活性关系，以及在材料科学、阿秒光谱和其他领域的应用。在高素质人才培养方面，这项研究将构成10篇研究生论文和5篇本科生论文的基础，并将为跨学科边界的合作贡献专门知识。