Size-selective Spectroscopic Studies of the Geometries, Intermolecular Vibrations and Intermolecular Potential Energy Surfaces of Molecular Clusters

点击翻译按钮获取中文摘要

In this project in the Experimental Physical Chemistry Program in the Chemistry Division, Peter Felker of UCLA will continue his spectroscopic studies of the structures and intermolecular potential energy surfaces of large neutral molecular clusters. This work relies on the technique of rotational coherence spectroscopy (RCS) which Felker helped develop in his lab at UCLA. The new studies include the addition of mass selection and ionization-detected Raman spectroscopy, fully quantum multidimensional calculations of potential energy surface via a collaboration with Prof. Zlatko Bacic of NYU, and examining very large cluster sizes (in some cases, greater than 20 moieties). Information will be obtained on geometries, potential energy surfaces, and the vibrational dynamics of the large clusters. %%% By exposing molecules in the gas phase to short, sharp pulses of laser light at the proper frequency, Prof. Felker can obtain information about the geometric structures of a relatively small, controlled number of interacting molecules. This information is very useful for understanding how molecules behave in the initial stages of a wide variety of chemical reactions. In addition, molecular clusters also exist in nature, such as in the atmosphere as well as in combustion flames. These experiments will thus provide information relevant to atmospheric as well as combustive processes and will also permit tests of various theories of intermolecular interaction. Ultimately a more detailed understanding of chemically significant systems will emerge which is relevant to areas such as the environment or biology.