NSF/DMR-BSF: Density Functionals for Predictive Excited-State Calculations of Solids

NSF/DMR-BSF：用于固体预测激发态计算的密度泛函

• 批准号: 1708892
• 负责人: Jeffrey Neaton
• 金额: $ 30.19万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1708892&HistoricalAwards=false
• 关键词: NSF; DMR; BSF; Density; Functionals

NONTECHNICAL SUMMARYThe National Science Foundation and the United States -- Israel Binational Science Foundation (BSF) jointly support this collaboration between a US-based researcher and an Israel-based researcher. The NSF Division of Materials Research funds this award, which supports research and education on the development of advanced computational methods for the simulation and prediction of materials properties.The discovery and development of new materials for converting sunlight into electricity is significantly limited by not having detailed understanding of how materials harvest light, transduce energy, and transport electric charge. All these phenomena are a challenge to model computationally as they involve excited electronic states. There exist computational methods with predictive power for such processes, but they come at significant computational cost. Developing more computationally efficient alternative approaches that offer similar accuracy would enable predictions for increasingly complex materials and would facilitate adapting such methods for materials discovery and design. This research project lays important groundwork toward the development of such efficient predictive approaches for real materials. Central to the proposed effort is outreach to and mentoring of next-generation computational materials theorists at all age levels, augmented by targeted recruitment of women and other underrepresented-minority undergraduate and graduate students. The PI will also organize tours of local research facilities for undergraduate, elementary, and middle-school students - as well as educators - in the Bay area and beyond. The US-based graduate students will travel to Israel to carry out research at the Israeli PI's group.TECHNICAL SUMMARYThe National Science Foundation and the United States -- Israel Binational Science Foundation (BSF) jointly support this collaboration between a US-based researcher and an Israel-based researcher. The NSF Division of Materials Research funds this award, which supports research and education on the development of advanced computational methods for the simulation and prediction of materials properties.In materials and condensed matter physics, the formalism of choice for quantitative determination of the band structure has long been many-body perturbation theory. This formalism has yielded excellent electronic structure predictions for many different classes of metals, semiconductors, and insulators. However, these predictions come at significant computational cost; extracting band structures from density functional theory (DFT), based on the single-electron energies and orbitals obtained from the solution of the Kohn-Sham equation, could alleviate this cost. The project involves a binational theoretical and computational collaboration to develop a new class of density functionals - optimally tuned range-separated hybrid (OTRSH) functionals - capable of predicting accurate quasiparticle band gaps and band structures, and optical spectra, including electron-hole interactions, for a range of complex solid-state materials, with greater computational efficiency than existing approaches. Using a benchmark set of well-studied materials, the team will: i) determine range-separation parameters that lead to the best match between OTRSH and the leading-edge excited-state method for each of these compounds; ii) develop the physics of the range-separation parameters; and iii) advance the OTRSH approach. The research team will then apply the OTRSH approach to a range of complex systems of contemporary interest, including transition metal oxides, Dirac materials, halide perovskites, and two-dimensional materials. The research activity will also address several open questions systematically, and ultimately develop an efficient DFT approach for understanding existing and predicting new excited-state phenomena in complex materials.Central to the proposed effort is outreach to and mentoring of next-generation computational materials theorists at all age levels, augmented by targeted recruitment of women and other underrepresented-minority undergraduate and graduate students. The PI will also organize tours of local research facilities for undergraduate, elementary, and middle-school students - as well as educators - in the Bay area and beyond. The US-based graduate students will travel to Israel to carry out research at the Israeli PI's group.

美国国家科学基金会和美国--以色列双国科学基金会(BSF)共同支持一名美国研究人员和一名以色列研究人员之间的合作。该奖项由美国国家科学基金会材料研究部门资助，该部门支持开发先进的计算方法来模拟和预测材料性质。由于对材料如何收集光线、转换能量和传输电荷没有详细的了解，新材料的发现和开发受到很大限制。所有这些现象都是对计算建模的挑战，因为它们涉及到激发电子态。对于这样的过程，存在着具有预测能力的计算方法，但它们会带来巨大的计算成本。开发计算效率更高的替代方法，提供类似的精度，将使对日益复杂的材料的预测成为可能，并将促进将这种方法应用于材料发现和设计。这一研究项目为开发这种针对真实材料的有效预测方法奠定了重要的基础。拟议工作的核心是对所有年龄段的下一代计算材料理论家进行外联和指导，并有针对性地招聘女性和其他代表不足的少数族裔本科生和研究生。PI还将为湾区及其他地区的本科生、小学生和中学生以及教育工作者组织当地研究设施的参观。美国的研究生将前往以色列，在以色列PI的小组进行研究。技术总结国家科学基金会和美国-以色列双国科学基金会(BSF)共同支持一名美国研究人员和一名以色列研究人员之间的合作。该奖项由美国国家科学基金会材料研究部资助，该部门支持开发先进的计算方法来模拟和预测材料的性质。在材料和凝聚态物理学中，定量确定能带结构的形式主义长期以来一直是多体微扰理论。这种形式主义已经为许多不同类别的金属、半导体和绝缘体产生了出色的电子结构预测。然而，这些预测带来了巨大的计算成本；根据Kohn-Sham方程的解获得的单电子能量和轨道，从密度泛函理论(DFT)中提取能带结构可以减轻这一成本。该项目涉及两国理论和计算合作，以开发一类新的密度泛函-最佳调谐范围分离混合(OTRSH)泛函-能够预测一系列复杂固态材料的精确准粒子带隙和能带结构以及光谱，包括电子-空穴相互作用，比现有方法具有更高的计算效率。使用一组经过充分研究的基准材料，该团队将：i)确定导致OTRSH和这些化合物的前沿激发态方法之间最佳匹配的范围分离参数；ii)发展范围分离参数的物理；以及iii)推进OTRSH方法。然后，研究小组将把OTRSH方法应用于一系列当代感兴趣的复杂系统，包括过渡金属氧化物、狄拉克材料、卤化物钙钛矿和二维材料。研究活动还将系统地解决几个公开的问题，并最终开发一种有效的DFT方法来了解复杂材料中现有的和预测新的激发态现象。拟议的努力的核心是接触和指导所有年龄段的下一代计算材料理论家，并有针对性地招募女性和其他代表不足的少数族裔本科生和研究生。PI还将为湾区及其他地区的本科生、小学生和中学生以及教育工作者组织当地研究设施的参观。这些美国研究生将前往以色列，在以色列派的小组进行研究。