This Faculty Early Career Development (CAREER) project, supported in the Analytical and Surface Chemistry Program, focusses on the development of a method for analyzing the structure and orientation of molecular species at buried interfaces. During the tenure of this three-year continuing grant, Professor Rowlen and her students at the University of Colorado will apply the newly developed technique of angle-resolved photoacoustic spectroscopy (ARPAS) to parallel studies of the relationship between the chemical nature of molecules and their orientation at surfaces and in thin films. In the first, the orientation of a variety of phenylazo dyes within zirconium phosphonate interlayers will be investigated and compared with each layer's nonlinear optical characteristics. Additionally, the relatively slow kinetics of orientational relaxation will be investigated for phenylazo dyes trapped within the transparent polymer matrix of an optical waveguide. In the second study, which focusses on understanding retention in liquid chromatography, the question of phase transitions within covalently immobilized alkylsilanes will be addressed by monitoring the degree of orientation as a function of temperature and solvent overlayer. Also during this grant period, Professor Rowlen will pursue an educational development plan that includes course development, acquisition of equipment for teaching laboratories, increased opportunities for undergraduate research participation, and introduction of industrial research internships for both undergraduate and graduate students. A method for analyzing the structure and orientation of molecular species at buried interfaces is of considerable technological importance. In this CAREER research project, angle-resolved photoacoustic spectroscopy will be used to develop new insights into molecular structure and orientation of phenylazo dyes and alkylsilane thin films that could lead to improved design of organic-based optical waveguides and also to an improved understanding of retention in liquid chromatography. The educational development aspects of this CAREER project should enrich and broaden the chemistry educational experience of University of Colorado students.
