Electron Delocalization in Linear Heterotrimetallic Compounds

美国国家科学基金会化学部的化学合成项目正在威斯康星大学麦迪逊分校约翰·贝里教授的监督下资助一项研究项目。该项目探索了用于电路和计算机的电子新方法。具体来说，该项目评估了含有金属原子链的分子的电导率。新的含金属化合物正在被制备，它们具有线状的线状结构。这些分子线只有一个金属原子厚，使它们成为可能的最薄的电路连接。为了测试这些分子线，三个设计方面正在进行测试。其中一个目标是研究将金属链连接到电极上的新分子。连接组是一种化学焊料，必须牢固地附着在导线和电极上。第二个目标是改变环绕在电线周围的化学保护层，它会影响电线内电子的能量（电压）。第三个目标是探索构成金属线本身的各种金属。我们感兴趣的是可能改变导线导电性或电阻的特定金属的影响。这项研究为学生提供了实践经验。一些艺术和科学推广工作正在进行中，以鼓励公众对这一科学领域的好奇心和认识。贝瑞教授帮助威斯康星水晶种植竞赛，这是一个旨在招募年轻学生参加stem相关活动的项目。同样，贝瑞教授和他的学生们正在参加旨在使化学工作者多样化的“大学前卓越学习充实机会计划”。美国国家科学基金会化学部的化学合成项目在威斯康星大学麦迪逊分校的John Berry教授的监督下资助了这项研究项目。这个项目涉及化学发现，但更广泛的科学影响超出了化学领域，包括物理学、电气工程、磁学和计算机科学。该项目研究了含有一维金属原子链的化合物的电学性质。这类化合物中合成用途最广泛的一类是扩展金属原子链（EMACs）和异金属扩展金属原子链（HEMACs），特别是由2,2 α -二吡啶酰胺（dpa）和相关配体支撑的金属原子链。研究人员探测和调整电子离域。更广泛的目标是评估这些线状化合物在分子电路中作为纳米级元件的效用。该团队与物理化学小组合作，评估新的HEMACs中的电子离域。一个主要的目标是评估电子通过HEMACs的传递是由分子内低能金属-金属拉伸振动控制的假设。为了支持这些合作努力，设计了特定的合成实验来评估与单分子电导相关的基本特性：锚基团效应，电子/空穴输运的前沿轨道能量调制，以及链内金属原子的系统调谐以进行分子整流。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。

The Chemical Synthesis Program within the Chemistry Division of the National Science Foundation is funding a research project under the supervision of Professor John Berry of the University of Wisconsin-Madison. The project explores new approaches to electronics used in electrical circuits and computers. Specifically, the project evaluates the electrical conductivity of molecules containing chains of metal atoms. New metal-containing compounds are being prepared that have a linear, wire-like structure. These molecular wires are only one metal atom thick, making them the thinnest circuit connection possible. In order to test these molecular wires, three design aspects are being tested. One aim is examining new molecules to attach the metal chains to electrodes. The linker group, a sort of a chemical solder, must attach strongly to both the wire and to the electrode. A second aim focuses on modifying the chemical sheathing that surrounds the wire, which affects the energies (voltage) of the electrons within the wire. The third aim is exploring diverse metals that comprise the wire itself. Of interest is the influence of particular metals that may change the conductivity or resistance of the wire. This research provides students with hands-on experience. A number of artistic and scientific outreach efforts are underway to encourage curiosity and public awareness of this area of science. Professor Berry helps with the Wisconsin Crystal Growing Competition, a program intended to recruit young students into STEM-related activities. Similarly, Professor Berry and his students are participating in the Pre-College Enrichment Opportunity Program for Learning Excellence, which aims to diversify the chemistry workforce. The Chemical Synthesis Program within the Chemistry Division of the National Science Foundation funds the research project under the supervision of Professor John Berry of the University of Wisconsin-Madison. This project involve chemical discoveries, but the broader scientific implications reach fields beyond chemistry, including physics, electrical engineering, magnetism, and computer science. The project examines the electrical properties of compounds containing one-dimensional metal atom chains. The most synthetically versatile class of such compounds are the extended metal atom chains (EMACs) and heterometallic extended metal atom chains (HEMACs), particularly those supported by 2,2ʹ-dipyridylamide (dpa) and related ligands. The researchers probe and tune electron delocalization. The broader goal is to assess the utility of these wire-like compounds as nanoscale components in molecular circuitry. The team collaborates with physical chemistry groups to assess electron delocalization in new HEMACs. A major goal is to assess the hypothesis that electron transport through HEMACs is gated by intramolecular, low-energy metal-metal stretching vibrations. To support these collaborative efforts, specific synthetic experiments are designed to assess fundamental properties related to single-molecule conductance: anchor group effects, modulation of frontier orbital energies for electron/hole transport, and systematic tuning of the metal atoms within the chains for molecular rectification.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.