Substrate-induced effects in the creation and decay of core excitations in ultrathin films of potassium chloride on copper

Substrate-induced effects in the creation and decay of 2p core excitations of K+ and Cl− in ultrathin films of KCl on Cu(1 0 0) surface have been studied using photoelectron, photoabsorption and resonant Auger spectra, excited by synchrotron radiation. The measurements were performed on different overlayers ranging from sub-monolayer coverages up to continuous thick films. It is demonstrated that the formation and decay of core excitations in thin films of KCl at Cu(1 0 0) surface is strongly influenced by the hybridization of excited states of K+ or Cl− origin with the metal substrate, which leads to the delocalization of the excited electron from the absorption site.