Molecular structure of polystyrene at air/polymer and solid/polymer interfaces. Gautam, K. S.; Schwab, A. D.; Dhinojwala, A.; Zhang, D.; Dougal, S. M.; Yeganeh, M. S. The University of Akron, Akron, OH, USA. Phys. Rev. Lett. (2000), 85(18), 3854-3857. CODEN: PRLTAO ISSN: 0031-9007. Journal written in English. CAN 134:42630 AN 2000:760491 CAPLUS

IR-visible sum-frequency generation (SFG) spectroscopy has been used in a total internal reflection geometry to study the mol. structure of polystyrene (PS) at PS/sapphire and PS/air interfaces, simultaneously. The sym. vibrational modes of the Ph rings dominate the SFG spectra at the PS/air interface as compared to the antisym. vibrational modes at the PS/sapphire interface. This indicates approx. parallel orientation of the Ph rings at the PS/air interface while nearly perpendicular orientation at the PS/sapphire interface, with respect to the surface normal.