CAREER: Structure Prediction and Design of Molecular Crystals with the GAtor Genetic Algorithm Package

材料研究部和先进网络基础设施部为该奖项提供资金。它支持计算研究，算法开发和预测分子晶体性质的教育。分子晶体用于许多技术应用，包括有机电子学、太阳能电池和非线性光学。它们对制药工业特别重要，因为大多数药物作为药物活性成分的分子晶体销售。分子晶体通过分子间的货车范德华相互作用结合在一起。与化学键不同，货车德瓦耳斯相互作用是由电子密度的量子力学波动引起的，这种波动导致了一种微弱但长程的静电吸引力。因为货车范德华力很弱，一个给定的分子可以结晶成一种以上的结构。不同的晶体结构可能导致具有明显不同的物理和化学性质的分子晶体几乎都是最受欢迎的结构。需要精确的计算来预测这场比赛的获胜者的结构，并能够设计新的分子晶体。通过计算机模拟的门户，PI将获得材料结构和成分的广阔配置空间。她将探索尚未合成的分子晶体的未知领域，并预测它们的性质，只知道它们的元素组成和量子力学定律。通过这种方式，有前途的候选分子晶体的具体应用，可以确定和用于指导合成effortes.Genetic算法（GAs）的最有前途的配置通过计算机模拟，实现“适者生存”的进化原则。组合群体中最合适结构的结构"基因"产生传播期望特征的"后代"，而随机突变用于保持多样性。这种方法是在一个GA软件包，GATor，计算机可以同时执行许多操作。PI将向更广泛的社区分发GATor软件包。该奖项还支持教育活动。教育计划的目标是：（一）传授具体学科的知识和技术技能;（二）发展科学和工程的基本技能，如解决问题、批判性思维和计算思维;（三）灌输专业技能，如文献研究、科学写作和演讲技能;（四）为学生的职业生涯做好准备;以及（v）扩大妇女和代表性不足的少数群体的参与。这将通过研究指导，研究生和本科生课程的教学，以及“物理和工程领域的女性领导者”系列研讨会来实现。技术总结材料研究部和高级网络基础设施部为该奖项提供资金。它支持计算研究，算法开发和分子晶体教育。该研究的目标是从第一性原理出发，通过计算结构预测和设计具有定制性质的分子晶体。这将通过开发一个通用的遗传算法（GA）包，GATor，能够进行基于能量和基于属性的优化，具有高精度和高效率。该研究计划包括两个阶段：（I）结构预测阶段寻求预测分子晶体的最稳定结构，给定单个分子的"棒图"-晶体结构预测盲测体现了巨大的挑战;和（II）晶体工程的第一原理阶段旨在设计具有目标性能的分子晶体，用于有机电子学和光电子学基于属性的遗传算法-计算材料设计中的一种新兴范式。PI将使用基于密度泛函理论的模拟，包括色散，以准确描述货车德瓦尔斯相互作用产生的势能景观。多体微扰理论方法将被用来精确地描述激子的性质。教育部分的目的是：（一）传授具体学科的知识和技术技能;（二）发展科学和工程的基本技能，如解决问题、批判性思维和计算思维;（三）灌输专业技能，如文献研究、科学写作和演讲技能;（四）为学生的职业生涯做好准备;以及（v）扩大妇女和代表性不足的少数群体的参与。这将通过研究指导、教授研究生和本科生课程以及"物理学和工程学领域的女性领导人"系列研讨会来实现。

NONTECHNICAL SUMMARYThe Division of Materials Research and the Division of Advanced Cyberinfrastructure contribute funds to this award. It supports computational research, algorithm development, and education on predicting properties of molecular crystals. Molecular crystals are used for many technological applications, including organic electronics, solar cells, and non-linear optics. They are of particular importance to the pharmaceutical industry because most drugs are marketed as molecular crystals of the pharmaceutically active ingredient. Molecular crystals are held together by van der Waals interactions between molecules. Unlike chemical bonds, van der Waals interactions arise from quantum mechanical fluctuations of the electron density that leads to a weak but long-ranged attractive electrostatic force. Because van der Waals interactions are weak, a given molecule may crystallize in more than one structure. Different crystal structures that could lead to molecular crystals that possess markedly different physical and chemical properties can all be nearly the most favored structure. Accurate calculations are required to predict the structure that is the winner of this competition and to be able to design new molecular crystals. Through the portal of computer simulations, the PI will gain access to the vast configuration space of materials structure and composition. She will explore the uncharted territory of molecular crystals that have not been synthesized yet and predict their properties knowing only their elemental composition and the laws of quantum mechanics. In this way, promising candidate molecular crystals for specific applications may be identified and used to guide synthesis efforts.Genetic algorithms (GAs) are guided to the most promising configurations by computer simulation that implements the "survival of the fittest" principle of evolution. Combining structural "genes" of the fittest structures in the population lead to "offspring" that propagate desirable features, while random mutations are employed to maintain diversity. This approach is implemented in a GA software package, GAtor, for computers that can perform many operations at the same time. The PI will distribute the GAtor software package to the broader community.This award also supports educational activities. The goals of the educational plan are to: (i) impart discipline-specific knowledge and technical skills; (ii) develop the foundational skills of science and engineering, such as problem solving, critical thinking, and computational thinking; (iii) instill professional skills, such as literature research, scientific writing, and presentation skills; (iv) prepare students for a career; and (v) broaden the participation of women and underrepresented minorities. This will be achieved via research mentoring, teaching of graduate and undergraduate courses, and the "Women Leaders in Physics and Engineering" seminar series.TECHNICAL SUMMARYThe Division of Materials Research and the Division of Advanced Cyberinfrastructure contribute funds to this award. It supports computational research, algorithm development, and education on molecular crystals. The goal of the proposed research is computational structure prediction and design of molecular crystals with tailored properties from first principles. This will be achieved by developing a versatile genetic algorithm (GA) package, GAtor, capable of conducting both energy-based and property-based optimization with high accuracy and high efficiency. The research plan comprises two phases: (I) the Structure Prediction phase seeks to predict the most stable structure(s) of a molecular crystal, given a "stick diagram" of a single molecule- a grand challenge embodied by the Crystal Structure Prediction blind test; and (II) the Crystal Engineering from First Principles phase seeks to design molecular crystals with target properties for applications in organic electronics and photovoltaics by property-based GAs- an emerging paradigm in computational materials design. The PI will use density functional theory based simulations that include dispersion to accurately describe the potential energy landscape arising from van der Waals interactions. Many-body perturbation theory methods will be used to accurately describe excitonic properties. The educational component is aimed to: (i) impart discipline-specific knowledge and technical skills; (ii) develop the foundational skills of science and engineering, such as problem solving, critical thinking, and computational thinking; (iii) instill professional skills, such as literature research, scientific writing, and presentation skills; (iv) prepare students for a career; and (v) broaden the participation of women and underrepresented minorities. This will be achieved via research mentoring, teaching of graduate and undergraduate courses, and the "Women Leaders in Physics and Engineering" seminar series.