Reflectance Change Caused By Diethyl Disulfide Adsorption on a Au(111) Thin Film

The fractional reflectance change ΔR/R of a 150 nm thick Au(111) film induced by diethyl disulfide (DEDS) adsorption was measured simultaneously with the fractional change in resistivity Δ𝛒/𝛒₀. The film surface was prepared by Ar⁺ sputtering, and the experiments were performed in a UHV chamber at a base pressure of 4x10^-10 Torr. Using a 670 nm diode laser, ΔR/R was measured to be -1.178% ± 0.003% with a corresponding Δ𝛒/𝛒 of 1.018% ± .005%.