Crystals on the Move

在这个由化学学部化学结构、动力学和机制B项目资助的项目中，辛辛那提大学化学系的Anna D. Gudmundsdottir教授正在分析晶体对光和机械力等外部刺激的反应。这些研究的重点是利用释放气体产生的动量在晶体材料中产生运动性或运动。这种机制类似于汽油机的运转。晶体对外部刺激的反应可能是相当戏剧性的，因为这样的晶体可以推动自己超越比自身尺寸大得多的距离，扭曲、卷曲、爬行、弯曲、断裂，甚至粉碎。由于动态晶体对光、热和机械力等外部刺激反应迅速，因此它们有可能用于各种智能材料应用，例如工业过程和设备中的传感器和执行器。本研究项目的跨学科性质为学生提供了广泛的教育培训。通过这项研究，学生将学会解决社会面临的苛刻的技术问题。重点将放在建立一个包容性和多样化的研究团队，在Gudmundsdottir实验室工作，包括来自科学领域代表性不足群体的高中和大学本科生。学生还将参加面向专业培训的教育活动。Gudmundsdottir研究小组将研究结晶叠氮化物和酯叠氮化物衍生物的光动力学和力学行为。在光照射下，这些物质解离形成分子N2气体和光产物。这些晶体的物理性质将通过获得它们的单晶x射线结构，索引晶体和测量它们的硬度来确定。此外，这些化合物的固态光反应性将通过对纳米晶体进行激光闪光光解来确定，以表征晶体内形成的瞬态。进一步的研究将确定这些瞬态的固态动力学和识别它们的光产物。总的来说，这些数据的分析将着眼于阐明详细的固态反应机制，并解释晶格如何控制叠氮化物和叠氮化物酯衍生物的分子反应性和大分子光动力学行为。这些光力学响应和分子固态光反应机制的研究将得到量子力学建模的支持。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。

In this project, funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professor Anna D. Gudmundsdottir of the Department of Chemistry at the University of Cincinnati is analyzing how crystals respond to external stimuli such as light and mechanical force. These studies focus on producing motility or movement in crystalline materials using momentum generated by releasing a gas. The mechanism is analogous to the operation of a gasoline engine. The response of crystals to external stimuli can be quite dramatic, as such crystals that can propel themselves over distances much larger than their own size, twist, coil, crawl, bend, fracture, or even shatter. Because dynamic crystals respond rapidly to external stimuli such as light, heat, and mechanical force, they have potential for use in various smart materials applications, such as sensors and actuators in industrial processes and devices. The interdisciplinary nature of this research project provides broad educational training for students. Through this research, students will learn to solve demanding technical problems facing society. Emphasis will be placed on building an inclusive and diverse research team to work in the Gudmundsdottir laboratory, including high school and college undergraduate students from groups underrepresented in science. Students will also be presented with educational activities geared towards their professional training. The Gudmundsdottir research team will study the photodynamic and mechanical behavior of crystalline divinyl azide and ester azide derivatives. Upon light exposure, these substances dissociate to form molecular N2 gas and photoproducts. The physical properties of these crystals will be determined by acquiring their single crystal X-ray structures, indexing the crystals, and measuring their hardness. In addition, the solid-state photoreactivity of these compounds will be determined by performing laser flash photolysis of nanocrystals to characterize the transients formed within the crystals. Further studies will determine the solid-state kinetics of these transients and identify their photo-products. Collectively, these data will be analyzed with an eye toward elucidating the detailed solid-state reaction mechanisms and toward explaining how the crystal lattice controls both the molecular reactivity and the macromolecular photodynamic behavior of divinyl azide and ester azide derivatives. These studies of photo-mechanical response and molecular solid-state photo-reaction mechanisms will be supported by quantum mechanical modeling.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.