<title>Atomic processes induced by relaxation of excitons in the bulk and on the surfaces of nonmetallic solids</title>

Abstract

Atomic processes induced by electronic excitation in the bulk and on surfaces of insulators are surveyed, emphasizing the difference in the atomic processes induced in different types of solids. The phenomena treated involve local lattice modification in the bulk and atomic emission from the surfaces. First the relaxation of holes and excitons in halides and oxides are compared and the way how the self-trapping of excitons leads to formation of defects is discussed. It is argued also that the self-trapping of holes and excitons is favorable in amorphous materials and the difference in the behaviors of holes and excitons in crystalline and amorphous SiO<SUB>2</SUB> is discussed. The relaxation of excitons on surfaces of ionic crystals and consequent atomic emission processes are argued. The relaxation of densely generated excitons and electron-hole pairs in the bulk is also discussed.