Metal-Ligand Electron-Transfer Complexes: Experimental Investigations of the Limits of Semiclassical Electron- Transfer Theory

在这个项目中，无机，生物无机和有机物 化学课程，哈利博士B。Gray和Jay R.温克勒的 加州理工学院将探索金属配体 电子转移（ET）过程的条件下，半经典ET 理论应该崩溃。为了确定隧道的作用， Ir（I）络合物，其中在高驱动力下的ET速率是 将研究比理论预测慢得多的速度。以帮助 在对ET率的理论解释中， 参数，温度和同位素对ET率的影响将是 测定本文系统地研究了双分子ET反应， Ir（I）二聚体将显示电子激发产物是否可以减少 有效的ET反应驱动力。光诱导ET反应 ET比预测的要慢的地区往往比 在类似的驱动力下的复合过程。基于这一事实， 弱耦合电子配位不饱和金属配合物 受体将被调查，以确定是否长寿命 可以通过直接光吸收来制备电荷转移态。 一些最重要的过程发生在化学和 生物系统涉及电子的转移和这种转移的速率。 转让往往是关键的运作过程。一 半经验的理论模型已被开发来解释这些 rates.在这项研究中，特别设计的铱络合物将用于 探讨这个理论用来描述电子速率的因素 转移这些研究对于基本了解 电子转移和新方法的开发，例如， 太阳能转换

In this project in the Inorganic, Bioinorganic, and Organometallic Chemistry Program, Dr. Harry B. Gray and Dr. Jay R. Winkler of the California Institute of Technology will explore metal-ligand electron-transfer (ET) processes under conditions where semiclassical ET theory should break down. To determine the role of tunneling, a series of Ir(I) complexes in which the ET rates at high driving forces are substantially slower than theoretically predicted will be studied. To aid in the theoretical interpretation of the ET rates, nuclear reoganization parameters, temperature, and isotope effects on ET rates will be determined. A systematic investigations of bimolecular ET reactions of Ir(I) dimers will show whether electronic excited products can reduce the effective ET reaction driving force. Photoinduced ET reactions in the region where ET is slower than predicted tend to be faster than recombination processes at comparable driving forces. Based on this fact, coordinatively unsaturated metal complexes with weakly coupled electron acceptors will be investigated to determine whether long-lived charge-transfer states can be prepared by direct light absorption. Some of the most important processes which occur in chemical and biological systems involve the transfer of electrons and the rate of such transfers is often critical to the operation of the process. A semi-empicical theoretical model has been developed to account for these rates. In this study specially designed iridium complexes will be used to probe the factors which this theory uses to describe the rate of electron transfer. Such studies are important both to the basic understanding of electron transfer and to the development of new methods of, for example, solar energy conversion.