GEOMETRIC AND ELECTRONIC STRUCTURAL STUDIES OF TRANSITION METAL DITHIOLENES

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者的研究机构。 三（二硫戊烯）过渡金属配合物由于其独特的物理性质和电子结构，在无机化学中引起了人们极大的兴趣。此外，三（二硫杂环戊烯）复合物是第一个离散的分子，拥有三角棱柱的几何形状，观察到的几个钼和钨酶，催化各种各样的基本生化反应的氧化活性位点的功能。在材料科学中，某些二硫纶配合物由于其在近红外区域的巨大吸收带而成为非线性光学器件和激光应用的候选材料。它们的可逆氧化还原化学已被用于生产半超导和超导材料和传感器。对酶促反应机理的理解或新功能材料的设计应基于对此类化合物的电子结构的透彻理解。二硫纶配体可以自由基和双自由基存在，并被描述为？非无辜的？这使得中心金属的氧化和自旋状态不明确，并且难以通过实验确定。氧化二硒烯配体的存在仍然是未知的。因此，在金属K-和L-边缘以及硫和硒K-边缘处的X射线吸收光谱非常适合于提供对这些系统的功能的基本电子结构的见解。此外，金属和配体EXAFS将有助于确定在固体和溶液状态的度量参数。硫和硒的EXAFS是完美的准备来衡量几何变化，从三角棱柱八面体的复杂的是通过测量配体间的距离依次减少。实验将结合准相对论密度泛函以及多重态计算，以获得更多的洞察实验数据。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Tris(dithiolene) transition metal complexes have piqued considerable interest in inorganic chemistry due to their fascinating physical properties and electronic structures. Moreover, tris(dithiolene) complexes were the first discrete molecules to possess trigonal prismatic geometry, a feature observed in the oxidized active sites of several molybdenum and tungsten enzymes that catalyze a wide variety of fundamental biochemical reactions. In material sciences, certain dithiolene complexes are candidate materials for nonlinear optical devices and laser applications due to their enormous absorption bands in the near-infrared region. Their reversible redox chemistry has been utilized in the production of semi- and superconducting materials and sensors. The understanding of enzymatic reaction mechanisms or the design of new functional materials should be based on a thorough understanding of the electronic structures of such compounds. Dithiolene ligands can exist as radicals and diradicals and are described as ?non-innocent?, which makes the oxidation and spin states of the central metal ambiguous and difficult to determine experimentally. The existence of oxidized diselenolene ligands is still unknown. Thus, x-ray absorption spectroscopy at the metal K-, and L-edges as well as the sulfur and selenium K-edges is ideally suited to provide fundamental electronic structure insights into the function of these systems. Additionally, metal and ligand EXAFS will assist in defining metric parameters in the solid and solution state. Sulfur and selenium EXAFS are perfectly poised to gauge the geometric change from trigonal prismatic to octahedral as the complex is sequentially reduced by measuring interligand distances. The experiments will be combined with quasi-relativistic density functional as well as multiplet calculations in order to obtain more insight into the experimental data.