Green Chemistry, Absolute Kinetics, and Signal Amplification with Molecular Nanocrystals

化学结构、动力学和机理B项目支持加州大学洛杉矶分校的Miguel A. Garcia-Garibay教授利用单晶x射线衍射、固态核磁共振和激光闪光光解化学动力学开发固态反应的稳健反应性模型。大量的化学过程是在光的作用下发生的，在没有外界试剂的情况下，在固态环境的刚性约束下，化学键可以断裂，新的化学键可以形成。这类反应所显示的化学控制水平与酶催化的反应所显示的化学控制水平相竞争。Garcia-Garibay教授的小组最近的发展表明，大约200纳米尺寸的晶体是分析和工程应用的理想新实现。该项目还研究了晶体中的量子链反应，其特点是每个光子吸收形成一个以上的产物，信号放大值高达一百万。该项目通过证明晶体中的反应可以使用悬浮在水中的纳米晶体样品扩大到数公斤的规模，为绿色化学和可持续性做出了关键贡献。固体中的反应在各种情况下都很重要。它们包括固体药品和消费品的不良分解，结构固体的降解和老化，以及固态器件的疲劳。然而，这一提议最广泛的科学和技术影响是帮助发展所需的智力和人类基础设施，以理解固体中的反应，现在在气相和溶液中很常见。通过保持高度支持和创造性的环境，促进材料科学和科学教育领域的职业发展，这位研究者成功地吸引了女性和少数族裔学生加入他的研究小组。PI已经与贸易技术学院（Trade Technical College）的教师建立了几项合作，该学院在洛杉矶市中心拥有非常多的西班牙裔和非裔美国人，这将鼓励他们的学生从事化学和材料科学方面的职业。

The Chemical Structure, Dynamics and Mechanisms B Program supports Professor Miguel A. Garcia-Garibay of the University of California, Los Angeles to develop robust reactivity models for reactions in the solid state using single crystal X-ray diffraction, solid-state nuclear magnetic resonance, and chemical kinetics by laser flash photolysis. A large number of chemical processes occur with light, and in the absence of external reagents, chemical bonds can be broken and new bonds can be made under the rigid constraints of solid state environments. Such reactions display levels of chemical control that compete with those observed for reactions catalyzed by enzymes. Recent developments by Professor Garcia-Garibay's group have shown that crystals with sizes in the ca. 200 nm scale are ideal for the novel implementation of analytical and engineering applications. This project also investigates quantum chain reactions in crystals, characterized by the formation of more than one product per photon absorbed, with signal amplification values as high as one million. This project makes a key contribution to green chemistry and sustainability by demonstrating that reactions in crystals can be scaled up to multi-kilogram scales using nanocrystals samples suspended in water. Reactions in solids are important in a variety of circumstances. They include the undesirable decomposition of solid pharmaceuticals and consumer products, the degradation and aging of structural solids, and the fatigue of solid state devices. However, the broadest scientific and technological impact of this proposal is to help develop the intellectual and human infrastructure needed to understand reactions in solids at a level now common for the gas phase and in solution. The investigator has been successful attracting women and minority students to his research group by maintaining a highly supportive and creative environment that fosters careers in materials science and in science education. The PI has established several collaborations with faculty at Trade Technical College, which has a very large Hispanic and African American population in downtown Los Angeles, and which will encourage their students to pursue careers in chemistry and materials science.