Incorporating MM Quadruple Bonds (M = Mo, W) into Organic Conjugated Pi-Systems. Fundamental Studies and Applications

化学结构、动力学和机制计划支持俄亥俄州立大学的马尔科姆·H·奇泽姆教授研究金属-金属(其中金属M是钼或钨)四键化合物的工作。特别强调了通过羧酸盐、硫代羧酸盐或酰胺基连接到M2中心的α-α‘-连接的噻吩基单元。化学合成和基础物理化学研究有助于金属有机聚合物的“智能设计”，它通过光谱扩展来增强有机光伏器件的特性。通过控制两个金属原子之间的距离、轨道能量匹配、构象和/或化学电荷来改变M2四键中心的电子耦合。这些分子系统可以被视为分子变阻器和整流器，因为它们作为信号和开关来报告它们的环境和氧化还原状态。用超快光谱(飞秒和纳秒-瞬时吸收、红外光谱和拉曼光谱)研究了配合物的电子光谱，考察了电荷离域随时间的变化。阳光是为数不多的规模足够大的可再生能源之一，可以满足世界的长期能源需求。这项研究考察了能够捕捉阳光并进一步转化为电能的新化学结构。Chisholm小组与物理学教授Epstein和电气工程教授Berger合作，研究了MM四键复合体作为太阳能电池和发光设备(LED)的光“收割器”的使用。这些金属络合物经过修饰和优化，以吸收大部分可用太阳光，并将这些光转换为可以运输或存储的能量形式。本科生和研究生与物理、电气工程和材料科学的小组互动。这一多学科项目为科学领域的职业提供了出色的教育背景，特别是在替代能源技术开发方面。特别值得注意的是与俄亥俄州光伏商业化倡议的联系，该倡议为学生提供实习和未来就业的机会，并为这些基础实验室研究产生的设备商业化提供了一个现成的平台。

The Chemical Structure, Dynamics and Mechanisms Program supports the work of Professor Malcolm H. Chisholm of The Ohio State University for the investigation of metal-metal (where metal, M, is molybdenum or tungsten) quadruplly-bonded compounds. Particular emphasis is given to alpha-alpha'-linked thienyl units attached to the M2 center by carboxylate, thiocarboxylate or amidinate groups. The chemical synthesis and fundamental physico-chemical studies contribute to the "intelligent design" of metallated organic polymers that enhance device characteristics of organic photovoltaics, OPV, by spectral expansion. The electronic coupling of the M2 quadruply bonded centers is modified by controlling the distance between the two metal atoms, their orbital energy matching, conformation and/or chemical charge. These molecular systems can be viewed as molecular rheostats and rectifiers as they act as signals and switches to report on their environments and redox states. The electronic spectra of the complexes are studied by ultra-fast spectroscopy (femtosecond- and nanosecond-transient absorption, IR and Raman) to examine the charge delocalization as a function of time. Sunlight is one of the few renewable energy sources available on a large enough scale to address the world's long-term energy needs. This research examines new chemical structures that are capable of capturing sunlight for further conversion into electrical energy. In collaboration with Professors Epstein in Physics and Berger in Electrical Engineering, the Chisholm group examines the use of the MM quadruply bonded complexes as light "harvesters" for solar cells and light emitting devices (LEDs). These metal complexes are modified and optimized to absorb large portions of the available solar light and to transfer this light into forms of energy that can be transported or stored. Undergraduate and graduate students interact with groups in physics, electrical engineering and material science. This multidisciplinary program provides an outstanding educational background for careers in science, particularly in the development of alternative energy technologies. Particularly noteworthy is the connection with the Ohio Photovoltaic Initiative for Commercialization which provides students with opportunities for internships and future employment as well as providing a ready platform for the commercialization of devices that arise from these fundamental laboratory studies.