9502808 Watson Oregon State University In this project in the Physical Chemistry program of the Chemistry Division, Prof. Philip Watson of the Chemistry Department of Oregon State University will investigate the properties of the gas-liquid interface at the molecular level. The compositional profile and the orientation of molecules in the surface will be investigated using the method of time-of-flight ion scattering and recoil spectrometry (TOF-SARS). The immediate goals of this project are 1) the construction and calibration of a liquid surface TOF-SARS system capable of generating uncontaminated and representative surfaces for low vapor pressure liquids and providing quantitative surface composition data and, 2) to establish the capabilities of the method to describe surface compositions and molecular orientations for a range of organic liquids and solutions. The properties of the liquid-surface interface pose one of the vexing problems in contemporary physical chemistry. The results of this research would contribute answers to questions such as: 1) what are the structure-property relationships that operate at the liquid-vapor interface?, 2) is it possible to formulate predictive rules that will link the segregation and orientation of molecules at the liquid surface with their structure, the presence of particular functionalities, and the presence of hydrogen-bonding?, 3) what is the surface concentration of solutions? how do experimental results compare with the predictions of thermodynamics and statistical mechanics?, 4) how do polymers fold at solution interfaces? Answers to these and other questions promise to be of significance in a number of important applied areas, such as the utilization of surface segregation in the mass transfer of pollutants.
