CAREER: Developing Quantum Nanogeochemistry for Molecular Studies and Inclusive Education

职业：为分子研究和全纳教育开发量子纳米地球化学

• 批准号: 1254127
• 负责人: Sara Mason
• 金额: $ 52.5万
• 依托单位: University of Iowa
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1254127&HistoricalAwards=false
• 关键词: CAREER; Developing; Quantum; Nanogeochemistry; Molecular

The Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation supports the research of Professor Sara E. Mason at the University of Iowa who will direct a project whose ultimate goal is to develop quantum nanogeochemistry as a platform, (1) to provide fundamental understanding of environmental nanoparticle (ENP) structure-reactivity, (2) to merge distinct theories of ENP reactivity, and, (3) to recruit community college (CC) students for training opportunities at the university level. The research strategy is to carry out Density Functional Theory (DFT)-based simulations on two classes of ENPs: Aqueous aluminum hydroxides modeled as Giant Aluminum Polycations (GAPs) and mineral-water interfaces modeled as Periodic Slab Models (PSMs). Reactivity questions that are suited to each model category are identified, and systematic simulation experiments are designed using comparisons to isolate what controls reactivity. The projects are designed to develop atomistic simulations results of both GAPs and PSMs into new conceptual models for ENP reactivity, a goal that will support or dispel existing theories. For this purpose, the distinctions between the models will be exploited, for example, GAPs are ideal models for tracking reactivity with orbital interactions because they are truly nanoparticulate, and fewer electronic states are expected to participate in interfacial bonding. Also, these aluminum hydroxides do not have d electrons, so they have a less complicated electronic structure than similarly structured iron hydroxides. Meanwhile, the PSM geometry is ideal for probing how adsorption-induced long range bond relaxation and relative energetics can be captured in a Bond Valence (BV) framework. Several of the proposed simulations will involve first time calculations, such as the later described DFT + COSMO (conduction-like screening model)+ (delta)H2O (partial explicit hydration) method for simulating the aqueous Al30 (GAP) and deriving surface-specific Hubbard U corrections to accurately model PSMs comprised of strongly correlated mineral oxides. The proposed work will enable improved predictions about the sequestration of aqueous contaminants that could ultimately lead to new water remediation strategies. Each research project will support the training of graduate and undergraduate students, and a major emphasis will be placed on the "Never Too Late to Learn" (NTLL) program and its mission to engage community college students in education and research activities that will extend opportunities to train them as the next generation scientists. Efforts to organize research outcomes into DFT databases that will be reported in the associated Data Management Plan, ensure that the fundamental information obtained from the atomistic simulations will be disseminated to the research community, regardless of any failure to pioneer the proposed conceptual models. The unified research and education plans are suited to principal investigator's strengths, background, and commitment to develop quantum nanogeochemistry as a vital field in environmental chemical science.

美国国家科学基金会化学部的环境化学科学项目支持萨拉·E。梅森在爱荷华州大学谁将指导一个项目，其最终目标是发展量子纳米地球化学作为一个平台，（1）提供基本的理解环境纳米粒子（ENP）的结构反应性，（2）合并不同的理论ENP反应性，以及（3）招募社区学院（CC）的学生在大学水平的培训机会。研究策略是对两类ENPs进行基于密度泛函理论（DFT）的模拟：以巨铝聚阳离子（GAP）为模型的氢氧化铝水溶液和以周期性板模型（PSM）为模型的矿物-水界面。反应性的问题，适合每个模型类别的确定，和系统的模拟实验设计使用比较，以隔离什么控制反应性。这些项目旨在将GAP和PSM的原子模拟结果开发成ENP反应性的新概念模型，这一目标将支持或消除现有理论。为此，将利用模型之间的区别，例如，GAP是跟踪轨道相互作用的反应性的理想模型，因为它们是真正的纳米颗粒，并且预计参与界面键合的电子态较少。此外，这些氢氧化铝没有d电子，因此它们的电子结构比类似结构的氢氧化铁更简单。同时，PSM几何是理想的探测吸附诱导的长程键弛豫和相对能量学可以捕获的键价（BV）框架。所提出的模拟中的几个将涉及第一时间计算，例如稍后描述的DFT + COSMO（类传导筛选模型）+（δ）H2O（部分显式水合）方法，用于模拟含水Al 30（GAP）并导出表面特异性Hubbard U校正以精确地模拟由强相关矿物氧化物组成的PSM。拟议的工作将能够改进对水污染物封存的预测，最终可能导致新的水修复策略。每个研究项目都将支持研究生和本科生的培训，重点将放在“学习永远不晚”（NTLL）计划及其使命上，即让社区学院的学生参与教育和研究活动，扩大培养他们成为下一代科学家的机会。将研究成果组织到DFT数据库中的努力将在相关的数据管理计划中报告，确保从原子模拟中获得的基本信息将传播给研究界，无论是否未能率先提出概念模型。统一的研究和教育计划适合首席研究员的优势，背景和承诺，以发展量子纳米地球化学作为环境化学科学的一个重要领域。