THE OPTICAL-PROPERTIES OF FLUID IODINE

The optical reflectivity and absorption coefficient of fluid iodine have been measured in the energy range 0.5-5.5 eV up to the liquid-gas critical point. The optical conductivity has been derived from the reflectivity spectra by using an oscillator fitting analysis. Near the critical point, two peaks around 2.2 and 3.4 eV appear in the optical conductivity spectrum. With decreasing temperature, the peak position around 2.2 eV changes little, while the peak around 3.4 eV shifts to the lower-energy side. The peak shift may arise from an increase of the intermolecular interaction.