Chemical Appl of Vibrational Circular Dichroism Spectroscopy

在这个由化学系实验物理化学计划支持的项目中，南加州大学的菲利普·斯蒂芬斯将利用实验和理论方法帮助开发应用于各种化学体系的振动圆二色谱(VCD)。初步研究将校准密度泛函理论(DFT)方法对大分子(80-200个原子)和含过渡金属分子的准确性。此外，还将检验考虑溶剂对预测结构和光谱影响的连续介质方法的可靠性。与绝对构型(AC)和构象分析(CA)的确定有关的特定立体化学问题将被讨论。VCD的应用将在超分子结构、金属分子、手性聚合物和同位素效应等几个重点领域得到开发。振动圆二色谱既是一种分析工具，也是一种结构工具。也就是说，这项技术既可以用来识别和表征化学体系，也可以用来确定所研究分子的三维结构。到目前为止，很大一部分应用涉及生物化学系统，如多肽、蛋白质、核苷酸和核酸。在这个项目中，VCD的使用将扩展到研究其他类型的化学体系，如有机金属催化剂。该项目的结果可能会在化工和制药行业中有用。

In this project supported by the Experimental Physical Chemistry Program of the Chemistry Division, Philip Stephens of the University of Southern California will use experimental and theoretical methods to help develop vibrational circular dichroism spectroscopy (VCD) for applications to a variety of chemical systems. Initial studies will calibrate the accuracy of Density Functional Theory (DFT) methodology for large molecules (80-200 atoms) and transition metal-containing molecules. In addition the reliability of continuum dielectric methods for including solvent effects on predicted structures and spectra will be examined. Specific stereochemical problems dealing with the determination of absolute configuration (AC) and conformational analysis (CA) will be addressed. Applications of VCD will be developed in several focussed areas, including supramolecular structure, metal-containing molecules, chiral polymers, and isotopic effects. Vibrational circular dichroism spectroscopy serves as both an analytical tool and a structural tool. That is, this technique can be used both to identify and characterize chemical systems as well as to determine the three-dimensional structure of the molecules under study. A large fraction of applications to date have involved biochemical systems, such as peptides, proteins, nucleotides and nucleic acids. In this project the use of VCD will be extended to studying other types of chemical systems, such as organometallic catalysts. The results of this project will likely be useful in the chemical and pharmaceutical industries.