High Resolution Studies of Jet-Cooled Large Molecules and Complexes Using Time-Domain and Interferometric Techniques

Peter Felker博士由实验物理化学项目资助，使用新开发的皮秒激光光谱技术对大型范德华配合物进行结构研究。这些被称为旋转相干光谱（RCS）和傅里叶变换受激发射泵浦光谱（FT-SEPS）的新技术为这类非常有趣的分子的结构和基态势能面提供了重要的信息。​RCS是一种基于转动量子拍现象的皮秒时域方法，将用于测量大型范德华配合物、氢键配合物和具有扭转自由度的物质的激发态旋转常数。这些实验的目的是获得与其他高分辨率技术难以研究的重要物种的几何形状有关的信息。FT-SEPS是受激发射泵浦光谱的干涉测量版本，将应用于类似物种的基态旋转振动水平结构的高分辨率研究。在这里，通过确定（基态）旋转常数来阐明几何形状是实验的主要目标。第二个目标是通过高分辨率振动光谱获得分子间和分子内势能表面的信息。

Dr. Peter Felker is supported by a grant from The Experimental Physical Chemistry Program to perform structural studies on large van der Waals complexes using newly developed picosecond laser spectroscopic techniques. These new techniques which are referred to as rotational coherence spectroscopy (RCS) and Fourier transform stimulated emission pumping spectroscopy (FT-SEPS) provide important information about the structure and ground state potential energy surfaces for this very interesting class of molecules. RCS is a picosecond time-domain method based on the rotational quantum beat phenomenon, and it will be used to measure excited state rotational constants of large van der Waals complexes, hydrogen-bonded complexes, and species with torsional degrees of freedom. The goal of these experiments is to obtain information pertaining to the geometries of important species that are difficult to study with other high resolution techniques. FT-SEPS, an interferometric version of stimulated emission pumping spectroscopy, will be applied to high resolution studies of the ground-state rovibrational level structures of similar species. Here, again, the elucidation of geometries via the determination of (ground-state) rotational constants is the primary goal of the experiment. A secondary goal is to obtain information about inter- and intra-molecular potential energy srufaces via high resolution vibrational spectroscopy.