Solid State Oxyfluorides

固态氟氧化物

• 批准号: 1005827
• 负责人: Kenneth Poeppelmeier
• 金额: $ 39万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1005827&HistoricalAwards=false
• 关键词: Solid; State; Oxyfluorides

Technical SummaryTechnologies that require high-performance nonlinear optical (NLO) materials with enhanced optical properties at the microscopic and macroscopic level depend on inorganic materials that exhibit large optical nonlinearities (possessing a dipole). The rational design of crystal structures, in particular noncentrosymmetric materials, and how to differentiate polar, polar-chiral, and chiral structures, is an ongoing theme in crystal engineering. These materials are essential for the modification of the amplitude, phase, or frequency of an optical signal. Polar distortions in metal centered octahedra are the origin of the nonlinear optical response in metal oxides. Octahedrally coordinated transition metal cations in groups 4,5,6 are unstable in mixed metal oxides with respect to intraoctahedral distortions, which can be understood through the second order Jahn-Teller theorem. This program explores research on noncentrosymmetric structures based on acentric transition metal oxyfluorides. These materials will provide a large and new class of solids with properties associated with piezoelectricity, pyroelectricity, ferroelectricity and second harmonic generation (SHG), all properties associated with noncentrosymmetric space groups. This work is supported by a grant from the Solid State and Materials Chemistry Program in the Division of Materials Research.Non-technical SummaryThe rational design of structures based on the chemical nature of molecular components, a longstanding and exciting research topic in organic solid-state chemistry, is an emerging theme of crystal engineering. Technologies that require high-performance nonlinear optical (NLO) materials with enhanced optical properties, however, depend on inorganic materials that exhibit large optical nonlinearities. Structures lacking inversion symmetry are a requirement for important current and future technologies that have been created by numerous inventions during the past two decades. These materials provide a large and new class of solids for studies in basic science associated with the noncentrosymmetric space groups. We propose an exploratory research program on these materials, which were highlighted recently in an article entitled "China's Crystal Cache" (Nature 2009, 457, 953-955). In this Nature article the critical national need for synthesis-based efforts to discover and to grow suitable crystals of these new materials was emphasized. This work is supported by a grant from the Solid State and Materials Chemistry Program in the Division of Materials Research at the National Science Foundation (DMR-1005827).

需要高性能非线性光学（NLO）材料具有增强的光学特性在显微镜和宏观水平上具有增强的技术摘要，取决于表现出较大光学非线性（具有偶极子）的无机材料。晶体结构的合理设计，尤其是非中心对称材料，以及如何区分极性，极性手续和手性结构，是晶体工程中持续的主题。这些材料对于修改光学信号的振幅，相或频率至关重要。金属中心八面体的极性扭曲是金属氧化物中非线性光学响应的​​起源。在混合金属氧化物中，相对于左右的扭曲，在组4,5,6中的八面体配位过渡金属阳离子在混合金属氧化物中是不稳定的，可以通过第二阶Jahn-Teller定理来理解。该计划探讨了基于分离过渡金属氧氟化物的非中心对称结构的研究。这些材料将提供一类新的固体类别，具有与压电性，上型，铁电性和第二谐波生成（SHG）相关的特性，所有特性都与非中心对称空间组相关。这项工作得到了材料研究部固态和材料化学计划的赠款的支持。没有技术总结基于分子成分的化学性质的结构的合理设计，这是有机固态化学方面的长期且令人兴奋的研究主题，是一个新兴的水晶工程主题。但是，需要具有增强光学特性的高性能非线性光学（NLO）材料的技术取决于表现出较大光学非线性的无机材料。缺乏反演对称性的结构是对过去二十年来许多发明创造的重要当前和未来技术的要求。这些材料为与非中心对称空间组相关的基础科学研究提供了一类新的固体。我们提出了一项有关这些材料的探索性研究计划，最近在题为“中国的水晶缓存”的文章中强调了这些材料（Nature 2009，457，953-955）。在本文中，强调了基于合成的努力发现和种植这些新材料的合适晶体的关键需求。这项工作得到了国家科学基金会（DMR-1005827）材料研究部固态和材料化学计划的赠款的支持。