PNNL

Abstract

The stopping of ions in solids is due to the energy loss as a result of the resistance to ion passage of the electronic and ionic nuclei in the material. When an ion penetrates a solid, it experiences a number of collisions. Energetic charged particles interact with both electrons and atoms in materials. Kinetic energy transfers to atoms can result in displacement of atoms from their original sites; thereby forming atomic-scale defects in the structure. Energy transfers to the target electrons (either bound or free) produces electron-hole pairs that can result in charging of pre-existing defects, localized electronic excitations, rupture of covalent and ionic bonds, enhanced defect and atomic diffusion, increased free energy, changes in phase transformation dynamics, as well as formation of atomic-scale defects. Such atomic collisions and ionization processes can modify the physical and chemical behavior of nanomaterials. This box will discuss irradiation-induced defect, address nanostructure engineering and radiation effects in nanomaterials, as well as the scientific challenges of ion-solid interactions.