Systematic Modulation of Lanthanide Physical Properties Using Functionalized Metallacrowns

在这项由化学系化学结构、动力学和机理B计划资助的项目中，密歇根大学安娜堡分校化学系的文森特·L·佩科拉罗教授正在开发一类含有稀土离子的金属大环。这项研究的目标是了解稀土离子的电子性质，这些离子对广泛的现代技术至关重要，如磁性材料、白光显示器和生物系统中的发光成像。此外，这些研究寻求开发新的分子纳米温度计的基础，该温度计可在广泛的温度范围内用于电子工业以及基础生物学研究，或最终用于临床测量细胞器或动物组织内的温度。该项目涉及有机、无机、材料化学和生物化学的交界点。这项研究非常适合各级科学家的教育。还计划通过一般兴趣介绍，向非专业公众进行宣传。例如，Pecoraro教授将在美国和欧洲发表与他的研究相关的公开演讲。Pecoraro教授有支持对科学方面代表性不足的学生进行教育和培训的历史，这些活动将继续下去。含有金属冠醚的镧系元素可以用来理解镧系元素的基本性质。由于这些离子的f轨道中含有电子，在d轨道内收缩，因此它们具有与分子磁性、磁致冷剂和发光发射相关的有趣性质。在这个项目中，金属杂多星将准备回答以下问题：(I)分子的对称性和配位数如何影响高发射或表现出单离子慢磁驰豫的稀土元素的电子结构？(Ii)金属冠能否用作被称为树状大分子的一类聚合物的发射核心，这种聚合物正被应用于化学和生物学的各种高级应用；以及(Iii)是否可以使用磁场来询问稀土元素的激发基态，以了解和计算基态混合到这些激发态的程度？该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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 & Mechanism B Program of the Chemistry Division, Professor Vincent L. Pecoraro of the Department of Chemistry at the University of Michigan, Ann Arbor is developing a class of metallamacrocycles containing lanthanide ions. The goal of this research is to understand the electronic properties of lanthanide ions that are critical to a vast range of modern technologies such as magnetic materials, white light displays, and luminescent imaging in biological systems. In addition, these studies seek to develop the foundation to make new molecular nanothermometers that can be used over a wide temperature range for applications in both the electronics industry as well as in basic biological research or eventually clinically to measure temperatures within cell organelles or animal tissue. The project lies at the interface of organic, inorganic, materials chemistry and biological chemistry. The research is well suited for the education of scientists at all levels. Through general interest presentation, outreach to the lay public is also planned. An example is that Professor Pecoraro will give public lectures related to his research both in the United States and Europe. Professor Pecoraro has a history of supporting the education and training for students underrepresented in science and these activities will continue. Lanthanide containing metallacrowns can be exploited to understand the fundamental properties of lanthanides. Because these ions contain electrons in their f-orbitals, which are contracted within the d-orbitals, they have interesting properties related to molecular magnetism, magnetocoolants and luminescent emission. In this project, metallacrowns will be prepared to answer the following questions: (i) How does the molecular symmetry and coordination number influence the electronic structure of lanthanides that are highly emitting or display single ion slow magnetic relaxation? (ii) Can metallacrowns be used as emitting cores for the class of polymers known as dendrimers, which are being applied for a variety of advanced applications in chemistry and biology; and (iii) Can one use magnetic fields to interrogate the excited ground states of lanthanides to understand, and calculate, the extent of ground state mixing to these excited states?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.