COUPLING OF THE DISSOCIATIVE ELECTRON-ATTACHMENT RESONANCES OF CO2 TO ANIONIC EXCITATIONS IN RARE-GAS SOLIDS

Significant sharp enhancements(FWHM less than or equal to 0.5 eV) are observed in electron stimulated desorption O- yields, obtained from small quantities of CO2 physisorbed on thick rare gas substrate films. The enhancements are positioned 0.3-0.4 eV below the lowest substrate exciton energy, and are attributed to a coupling of the (electron plus exciton) core-excited anion resonances of the rare gas atoms to the dissociative temporary molecular anion states of the co-adsorbed CO2 at the solid's surface. This causes a transfer of the charge and excitation energy to the co-adsorbate.