Polymorphism of Organic Materials

该奖项由威斯康星大学麦迪逊分校材料研究部固态材料化学项目授予，旨在研究有机材料的多态性。多态性是指同一分子结晶成具有不同性质的不同结构的能力，就像碳结晶成金刚石、石墨和C60一样。该项目将通过交叉成核合成新的多晶，并将使用多晶来理解非晶固体晶体生长的不寻常模式。该项目建立在最近的观察基础上，通过播种可以发现罕见的手性分子晶体形式，并且一些多晶型显示出从玻璃态快速，无扩散的晶体生长，而另一些则没有。该项目将研究有机和药物材料结晶中的两个广泛的基本问题：(i)对映体固溶体的合成，其中一个对映体的过量增加，以及（ii）非晶态材料的结晶。第一个项目的重点是手性分子的种子诱导晶体生长。该项目的第二部分将是关于从过冷液体中形成多晶型分子的晶体生长。这两个项目都试图解决晶体生长的基本机制。晶体多晶的研究服务于材料研究的两个任务：合成新材料和了解结构-性能关系。预计这项研究将影响几个技术领域。多晶体的发现和控制对于开发药物、颜料、炸药和其他材料至关重要。更好地理解非晶态材料的结晶将促进非晶态药物、硅、金属、陶瓷和聚合物的开发。这项研究跨越材料科学和化学，将为本科生和研究生提供多学科的教育机会。这项研究将涉及来自本科生研究学者项目的学生，该项目帮助一年级和二年级的本科生通过与威斯康星大学麦迪逊分校的教职员工和研究人员合作，获得研究的实践经验。

This award to University of Wisconsin-Madison by the Solid State Materials Chemistry program in the Division of Materials Research is to investigate the polymorphism of organic materials. Polymorphism is the ability of the same molecule to crystallize in different structures with distinct properties, as the ability of carbon to crystallize as diamond, graphite, and C60. This project will synthesize novel polymorphs by cross-nucleation and will use polymorphs to understand an unusual mode of crystal growth from amorphous solids. The project builds on recent observations that rare crystal forms of chiral molecules may be discovered by seeding and that some polymorphs show fast, diffusionless crystal growth from the glassy state, while others do not. This project will study two broad fundamental questions in the crystallization of organic and pharmaceutical materials: (i) synthesis of solid solutions of enantiomers, with an enhanced excess of one enantiomer, and (ii) the crystallization of amorphous materials. The first project focuses on the seeding-induced crystal growth of chiral molecules. The second part of the project will be on the crystal growth of polymorph-forming molecules from supercooled liquids. Both projects seek to address fundamental mechanisms of crystal growth.Studying crystal polymorphs serve two missions of materials research: to synthesize new materials and to understand structure-property relations. It is anticipated that this research will impact several technological areas. The discovery and control of polymorphs is critical in developing drugs, pigments, explosives, and other materials. Better understanding of the crystallization of amorphous materials will advance the ability to develop amorphous drugs, silicon, metals, ceramics, and polymers. This research spans materials science and chemistry and will provide multidisciplinary educational opportunities for undergraduate and graduate students. The research will involve students from the Undergraduate Research Scholars program, which helps first- and second-year undergraduates to gain hands-on experience in research by working with the faculty and research staff at University of Wisconsin-Madison campus.