Solid-State Oxides and Oxide-Fluorides

固态氧化物和氧化物-氟化物

• 批准号: 1904701
• 负责人: Kenneth Poeppelmeier
• 金额: $ 50.82万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1904701&HistoricalAwards=false
• 关键词: Solid; State; Oxides; Oxide; Fluorides

Non-Technical SummaryLasers were discovered in 1960 by scientists at Bell Laboratories. A year after the initial discovery, a group of researchers demonstrated that the high electric fields produced by a laser pulse converted the light passing through a quartz crystal from one color to another (red to green) via a nonlinear optical (NLO) process called second-harmonic generation. Since then, NLO materials like quartz have played a key role in advancing frontiers in laser science. NLO activity and other exciting properties are allowed in materials where inversion symmetry in broken, which are known as noncentrosymmetric (NCS) solids. Through this project, which is supported by the Solid State and Materials Chemistry program at NSF, Prof. Poeppelmeier's group at Northwestern University advances the understanding how chemistry can be used to create materials with broken inversion symmetry and connect atomic structure to properties. A variety of synthetic approaches are used to control the alignment of the building blocks that make up a crystal structure. Their growth of large, high-quality crystals of NCS materials enables detailed investigation of the connection between atomic structure and properties in NCS materials. The research is carried out by undergraduate and graduate students, who in the process of this project are trained in state-of-the-art solid state chemistry. Additionally, the students are encouraged to participate in a myriad of outreach activities that the PI himself is involved in.Technical SummaryAdvances in laser technology have led to a significant increase in the application of laser systems in areas ranging from eye surgery to particle acceleration. Emerging laser technologies require high-performance materials that can efficiently convert the frequency of laser radiation through nonlinear optical (NLO) processes, such as second-harmonic generation and parametric amplification. The NLO properties necessary for applications in tunable laser systems, as well as other technologically useful properties such as piezoelectricity, ferroelectricity, and pyroelectricity, are available in crystalline materials lacking inversion symmetry, known as noncentrosymmetric (NCS) solids. This project, which is supported by the Solid State and Materials Chemistry program at NSF, develops targeted synthesis methods for NCS materials using hydrothermal, solvothermal, and solid-state methods to control the alignment of anionic basic building units such that useful properties can be realized. These synthetic efforts are guided by chemical knowledge as well as machine learning methods that elucidate important trends from large amounts of experimental data. The growth of large, high-quality crystals enables structural characterization with single crystal and powder x-ray diffraction along with NLO and other property measurements to determine structure-property relationships. Examination of the syntheses, structures, and properties of NCS materials is expected to lead to discovery of new NCS materials and new strategies for future NCS materials synthesis.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.

激光器是1960年由贝尔实验室的科学家发现的。在最初发现一年后，一组研究人员证明，激光脉冲产生的高电场通过称为二次谐波产生的非线性光学（NLO）过程将通过石英晶体的光从一种颜色转换为另一种颜色（红色到绿色）。从那时起，石英等非线性光学材料在推进激光科学前沿方面发挥了关键作用。在反转对称性破缺的材料中，NLO活性和其他激发性质是允许的，这被称为非中心对称（NCS）固体。通过这个由NSF固态和材料化学计划支持的项目，西北大学的Poeppelmeier教授小组推进了对化学如何用于创建具有破缺反转对称性的材料并将原子结构与性质联系起来的理解。各种合成方法用于控制构成晶体结构的构建块的排列。他们生长的NCS材料的大，高质量的晶体，使原子结构和性能之间的联系在NCS材料的详细调查。这项研究是由本科生和研究生进行的，他们在这个项目的过程中接受了最先进的固态化学培训。此外，鼓励学生参加PI自己参与的各种推广活动。技术摘要激光技术的进步导致激光系统在从眼科手术到粒子加速等领域的应用显着增加。新兴激光技术需要高性能材料，这些材料可以通过非线性光学（NLO）过程（例如二次谐波产生和参量放大）有效地转换激光辐射的频率。在可调谐激光系统中应用所必需的NLO性质，以及其他技术上有用的性质，如压电性、铁电性和热电性，在缺乏反转对称性的晶体材料中可用，称为非中心对称（NCS）固体。该项目由NSF的固态和材料化学计划支持，使用水热，溶剂热和固态方法开发NCS材料的有针对性的合成方法，以控制阴离子基本结构单元的排列，从而实现有用的性能。这些合成工作由化学知识和机器学习方法指导，这些方法从大量实验数据中阐明了重要趋势。大的、高质量晶体的生长使得能够利用单晶和粉末X射线衍射沿着NLO和其他性质测量来进行结构表征，以确定结构-性质关系。通过对NCS材料的合成、结构和性能的研究，有望发现新的NCS材料和未来NCS材料合成的新策略。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Synthesis, crystal structure, and magnetic properties of a one-dimensional chain antiferromagnet NiC2O4·2NH3

一维链状反铁磁体NiC2O4·2NH3的合成、晶体结构及磁性能

• DOI: 10.1016/j.jssc.2022.123360
• 发表时间: 2022
• 期刊: Journal of Solid State Chemistry
• 影响因子: 3.3
• 作者: Ding, Fenghua;Griffith, Kent J.;Zhang, Chi;Zhan, Jing;Lu, Hongcheng;Poeppelmeier, Kenneth R.
• 通讯作者: Poeppelmeier, Kenneth R.

Machine-Learning-Assisted Synthesis of Polar Racemates

• DOI: 10.1021/jacs.0c01239
• 发表时间: 2020-04-22
• 期刊: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
• 影响因子: 15
• 作者: Nisbet, Matthew L.;Pendleton, Ian M.;Poeppelmeier, Kenneth R.
• 通讯作者: Poeppelmeier, Kenneth R.