Photoisomerization: New Complexes, Circular Dichroism, and the Faraday Effect

光异构化：新配合物、圆二色性和法拉第效应

• 批准号: 1856492
• 负责人: Jeffrey Rack
• 金额: $ 39万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1856492&HistoricalAwards=false
• 关键词: Photoisomerization; New; Complexes; Circular; Dichroism

Complexes that undergo a change in color when exposed to light are termed photochromic. These types of compounds have a variety of applications in diverse settings including computing and photonic materials. This research program is dedicated to understanding how these photochromic compounds (and ultimately materials) interact with light to generate color changes. Most of the known photochromic compounds operate through a light-triggered molecular rearrangement that occurs on an ultrafast timescale (picosecond). There are many unanswered questions regarding how molecules convert light energy into potential energy to initiate molecular rearrangement. A new aspect of this research program is the development of new optical experimental techniques to monitor structural and magnetic changes in molecules on very short timescales. Professor Jeffrey Rack at the University of New Mexico is engaged in a series of outreach efforts to encourage students to pursue careers in STEM disciplines. He has a particular interest in supporting Native American students, Hispanic students, and women in their career development. The project provides experience in the design of instrumentation to address questions at the interface between chemistry and physics. The multidisciplinary nature of the project demand that the student researchers be aware of literature contributions in disparate research areas.This research award in the Chemical Structure, Dynamics and Mechanisms B Program within the Division of Chemistry at NSF supports the research efforts of Professor Jeffrey Rack at University of New Mexico to investigate a new class of transition metal complexes which change structure and color when exposed to solar radiation (light). These studies focus on discovering the kinetic and thermodynamic parameters for the action of this unique family of chromophores that utilize light to break and make bonds on a very fast timescale. The mode of action in these complexes is an excited state isomerization of the bound sulfoxide ligand. In addition, two new instrumental techniques are introduced. First, Professor Rack is studying the development of a time-resolved circular dichroism to monitor chirality changes, not only in transition metal sulfoxide complexes, but also in chiral sulfoxide compounds. Second, Professor Rack is developing a Faraday rotation spectroscopic instrument, which monitors magnetic fields in compounds and materials. This technique is used to monitor the creation and fate of triplet states in molecular photophysics. Professor Jeffrey Rack at the University of New Mexico is engaged in a series of outreach efforts to encourage students to pursue careers in STEM disciplines, and has a particular interest in supporting Native American students, Hispanic students, and women in their career development.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.

当暴露于光时发生颜色变化的复合物被称为光致变色。这些类型的化合物在包括计算和光子材料在内的各种环境中具有各种应用。该研究计划致力于了解这些光致变色化合物（以及最终材料）如何与光相互作用以产生颜色变化。大多数已知的光致变色化合物通过发生在超快时间尺度（皮秒）上的光触发分子重排来操作。关于分子如何将光能转化为势能以引发分子重排，有许多未解之谜。这项研究计划的一个新方面是开发新的光学实验技术，以监测分子在很短的时间尺度上的结构和磁性变化。新墨西哥州大学的杰弗里·拉克教授正在开展一系列外展工作，鼓励学生从事STEM学科的职业。 他有一个支持美洲原住民学生，西班牙裔学生和妇女在他们的职业发展特别感兴趣。 该项目提供了在仪器设计的经验，以解决在化学和物理之间的接口问题。该项目的多学科性质要求学生研究人员了解不同研究领域的文献贡献。化学结构研究奖，NSF化学部的动力学和机制B计划支持新墨西哥州大学的Jeffrey Rack教授的研究工作，研究一类新的过渡金属络合物，当暴露在太阳光下时，它们会改变结构和颜色。辐射（光）。这些研究的重点是发现这个独特的发色团家族的动力学和热力学参数，这些发色团利用光在非常快的时间尺度上断裂和形成键。在这些配合物中的作用模式是结合的亚砜配体的激发态异构化。此外，还介绍了两种新的仪器技术。首先，Rack教授正在研究开发一种时间分辨圆二色性来监测手性变化，不仅在过渡金属亚砜络合物中，而且在手性亚砜化合物中。其次，Rack教授正在开发一种法拉第旋转光谱仪器，它可以监测化合物和材料中的磁场。这种技术在分子电子物理学中被用来监测三重态的产生和命运。新墨西哥州大学的杰弗里·拉克教授从事一系列外展工作，鼓励学生从事STEM学科的职业，并特别有兴趣支持美洲原住民学生，西班牙裔学生，该奖项反映了NSF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进行评估，被认为值得支持的搜索.

项目成果

Donor–Acceptor Conjugated Copolymers Containing Transition-Metal Complex: Intrachain Magnetic Exchange Interactions and Magneto-Optical Activity

• DOI: 10.1021/acs.chemmater.2c01433
• 发表时间: 2022-06
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Xunshan Liu;Jiaze Xie;J. Niklas;Emigdio E. Turner;Dafei Yuan;John S. Anderson;J. Rack;O. Poluektov;Luping Yu

A Future Perspective on Phototriggered Isomerizations of Transition Metal Sulfoxides and Related Complexes

过渡金属亚砜及相关配合物光引发异构化的未来展望

• DOI: 10.1021/jacs.0c08820
• 发表时间: 2021
• 期刊: Journal of the American Chemical Society
• 影响因子: 15
• 作者: Vittardi, Sebastian B.;Thapa Magar, Rajani;Breen, Douglas J.;Rack, Jeffrey J.
• 通讯作者: Rack, Jeffrey J.

Trifluoromethylated Phenanthroline Ligands Reduce Excited-State Distortion in Homoleptic Copper(I) Complexes

• DOI: 10.1021/acs.inorgchem.9b03146
• 发表时间: 2020-03-02
• 期刊: INORGANIC CHEMISTRY
• 影响因子: 4.6
• 作者: Livshits, Maksim Y.;Reeves, Brian J.;Rack, Jeffrey J.
• 通讯作者: Rack, Jeffrey J.

Manipulating Excited State Properties of Iridium Phenylpyridine Complexes with “Push–Pull” Substituents

操纵具有“推拉”取代基的铱苯基吡啶配合物的激发态性质

• DOI: 10.1021/acs.inorgchem.2c02269
• 发表时间: 2022
• 期刊: Inorganic Chemistry
• 影响因子: 4.6
• 作者: Turner, Emigdio E.;Breen, Douglas J.;Kosgei, Gilbert;Crandall, Laura A.;Curtin, Gregory M.;Jakubikova, Elena;O’Donnell, Ryan M.;Ziegler, Christopher J.;Rack, Jeffrey J.
• 通讯作者: Rack, Jeffrey J.

Evidence for a lowest energy 3 MLCT excited state in [Fe(tpy)(CN) 3 ] −

[Fe(tpy)(CN) 3 ] 中存在最低能量 3 MLCT 激发态的证据 —

• DOI: 10.1039/d1cc01090e
• 发表时间: 2021
• 期刊: Chemical Communications
• 影响因子: 4.9
• 作者: Vittardi, Sebastian B.;Magar, Rajani Thapa;Schrage, Briana R.;Ziegler, Christopher J.;Jakubikova, Elena;Rack, Jeffrey J.
• 通讯作者: Rack, Jeffrey J.