Incident beam diffraction in electron stimulated desorption

We describe a new experimental technique utilizing incident beam diffractio n in electron stimulated desorption (ESD) to determine the initial atomic b onding structure of desorbates. Diffraction in ESD can provide detailed inf ormation about the ground stale surface bonding geometry of the absorber wi th sub-angstrom resolution of bond vectors. We discuss the role of electron diffraction in ESD, and demonstrate these ideas with experimental measurem ents of Cl+ ion ESD from chlorinated Si(111)-(7 x 7) and (1 x 1) surfaces. (C) 2000 Elsevier Science B.V. All rights reserved.