The optical constants n and k for polystyrene in both bulk and chemically deposited thin-film form have been measured by the reflectance vs angle of incidence technique in the wavelength region from 584 to 2000 Å. Four angles of incidence were used, and the effects of monochromator polarization were eliminated experimentally. The results differ from previously published data for the bulk form. The electron-energy-loss function - Im(1/∊) was calculated from n and k determined for the thin films and compared with values obtained previously by characteristic electron-energy-loss techniques. These two methods yield the same structure in the energy-loss function; however, there remains some difference in the magnitude of the 6.9-eV loss relative to the background.
J. T. SHAPIRO and R. P. MADDEN, "Optical Constants of Polystyrene in the Vacuum Ultraviolet," J. Opt. Soc. Am. 58, 771-775 (1968)