The optical constants, n and k, and energy-loss functions of vacuum evaporated Cd and Tl films were determined in the wavelength region 500 to 2800 Å from reflectance measurements made at 20°, 45°, and 70° angles of photon incidence. The energy-loss functions were found to have maxima at 8.55 and 10.25 eV for Cd and Tl, respectively, as compared to the values of 8.1 and 9.6 eV found from characteristic electron energy-loss experiments.
T. M. JELINEK, R. N. HAMM, E. T. ARAKAWA, and R. H. HUEBNER, "Optical Constants of Vacuum Evaporated Films of Cd and Tl in the Vacuum Ultraviolet," J. Opt. Soc. Am. 56, 185-188 (1966)