Hydrothermal Brines: New Media for the Synthesis and Crystal Growth of Materials

本项目探索具有潜在有用性能的新型固态材料。来自固态和材料化学项目的资金支持继续开发合成新材料的新方法，特别是高温水热技术，该技术在异常高温（700摄氏度）和压力（20,000 psi）的水中进行反应。这些条件与地球深处的条件相似，经常导致新产品的高质量单晶的形成。这种极端的反应条件在世界上任何其他实验室几乎都是未知的。正因为如此，可以制备出全新的、意想不到的化合物，并挑战现有的结构和键合理论。这些不寻常的新材料中有许多具有意想不到的有用特性。其中一些可用于激光、超高分辨率微机械加工、新型磁性器件，甚至可能用于量子通信和量子计算机。本研究直接适用于NSF大构想之一：“量子飞跃：引领下一次量子革命”。在这个项目中使用的新技术通常会产生特殊尺寸和质量的晶体，因此它们可以比许多其他材料更详细地研究。对这些新型晶体材料的全面研究为下一代新材料提供了重要的见解。因为这项研究中使用的技术在世界上几乎没有其他地方使用过，所以这个项目的学生学习了一套独特的技能，使他们能够成为下一代研究人员。该项目由材料研究部固态与材料化学项目资助，是高温水热合成新固态化合物的下一阶段扩展。本项目的主要重点是研究一类新的矿化剂，即热液卤水。卤水是含有卤化物和碳酸盐等浓缩盐的液体。这种流体几乎没有得到系统的实验室研究，但初步调查表明，它们是合成和单晶生长大量新型有趣化合物的极好介质。该计划侧重于开放壳第一行过渡金属离子，由一系列氧阴离子构建块络合。这些包括钒酸盐、磷酸盐、日耳曼酸盐、没食子酸盐、锡酸盐和其他含有各种结构和桥接特性的相关构建块。新晶体表现出许多吸引人的物理性质，包括偏心、极性和受挫的磁性行为。该研究针对具有这些理想性能的特定类型的化合物，用于新型压电材料、多铁性材料和类似材料。由于这项研究中使用的合成技术在世界上几乎没有其他地方使用，因此该计划的学生将学习一套独特的技能，使他们能够成为下一代研究人员。该奖项反映了美国国家科学基金会的法定使命，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。

Non-Technical SummaryThis project explores new solid-state materials with potentially useful properties. The funding from the Solid State and Materials Chemistry Program supports continued development of a novel approach to synthesis of new materials, specifically a high temperature hydrothermal technique in which reactions are performed in water at exceptionally high temperatures (700 degrees C) and pressures (20,000 psi). These conditions are similar to those deep within the Earth, and often result in formation of high quality single crystals of new products. Such extreme reaction conditions are almost unknown in any other laboratories in the world. Because of this, compounds can be prepared that are completely new and unanticipated, and challenge existing theories of structure and bonding. Many of these unusual new materials have unexpectedly useful properties. Some can be used in lasers, ultrahigh resolution micromachining, new magnetic devices and possibly quantum communication and quantum computers. This research is directly applicable to one of the NSF Big Ideas: "The Quantum Leap: Leading the Next Quantum Revolution". The new techniques used in this program typically lead to crystals of exceptional size and quality, therefore they can be studied in greater detail than many other materials. The comprehensive investigation of these new crystal materials provides important insights into the next generation of new materials. Because the techniques employed in this research are used almost nowhere else in the world, the students in this program learn a unique skill set enabling them to stand out as the next generation of researchers.Technical SummaryThis program, funded by the Solid State and Materials Chemistry program in the Division of Materials Research, is a next-stage extension of high temperature hydrothermal synthesis as a route to new solid-state compounds. The primary emphasis in this project is on the investigation of a new class of mineralizers, namely hydrothermal brines. Brines are fluids containing concentrated salts like halides and carbonates. Such fluids have received almost no systematic laboratory study, but preliminary investigation suggests that they are excellent media for the synthesis and single crystal growth of an enormous new class of interesting compounds. The program focuses on open shell first row transition metal ions that are complexed by a range of oxyanion building blocks. These include vanadates, phosphates, germanates, gallates, stannates and other related building blocks containing a variety of structural and bridging characteristics. The new crystals exhibit a number of attractive physical properties including acentricity, polarity and frustrated magnetic behavior. The research targets specific types of compounds with these desirable properties for new piezoelectrics, multiferroics and similar materials. Because the synthesis techniques employed in this research are used almost nowhere else in the world, the students in this program learn a unique skill set enabling them to stand out as the next generation of researchers.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.