Reaction of Cu and Cl₂ stimulated by synchrotron radiation

Abstract

Light-induced reactions of poly-Cu with Cl₂ and the formation of CuCl _x films were studied in the spectral range of 105–400 nm by using synchrotron radiation. The efficiencies of the reactions with Cl₂ pressures between 10⁻⁵ and 10⁻² mbar were determined from the height distributions of spatial structures in the CuCl _x films. The heights typically range from 10 to 10⁴ nm. An efficiency of about 10⁷ CuCl _x molecules per dissociated Cl₂ molecule is observed at high Cl₂ exposures. At low Cl₂ pressures CuCl _x formes anisotropically in the irradiated area. The efficiency is determined by light-induced surface processes supporting the build up of CuCl _x in the long wavelength range and competing processes at short wavelengths which reduce the efficiency.