Surface Electron Energy Loss Fine Structure

Fine structure extending several hundred eV in kinetic energy below a CEELS peak, analogous to EXAFS, have been observed in REELS. Bond lengths of adsorbed species can be determined from Surface Electron Energy-Loss Fine Structure (SEELFS) using a modified EXAFS formalism. 

M. De Crescenzi. Phys. Rev. Letts. 30,1949,1987. Use of surface electron energy-loss fine structure (SEELFS) to determine oxygen-nickel bond length changes for oxygen absorbed on Ni (100) on a function of coverage from 0 to 1.0 monolayer. 

Surface electron energy loss fine structure. 

SEELFS Surface Electron Energy Loss Fine Structure... 

Surface electron energy loss fine structure (77, 121, 122)... 

SEELES SEXAES SIMS SPLEED Surface Electron Energy Loss Fine Structure Surface Extended X-ray Absorption Fine Sfructure Secondary Ion Mass Spectroscopy Spin-Polarized LEED ... 

EXELFS Extended X-ray Energy Loss Fine Structure A fine-structure technique similar to EXAFS, except that 60-300 KeV electrons rather than photons excite core-holes. Like EXAFS, this techniques is not explicitly surface sensitive. 

P.R. Watson. Critical Compilation of Surface Structures Determined by Surface Extended X-Ray Absorption Fine Stmcture (SEXAFS) and Surface Extended Electron Energy Loss Spectroscopy (SEELFS). J. Pins. Chem. Ref Data 21 123 (1992). 

The experimental detection and quantification of surface species on in situ soil particles and other natural colloids is a difficult area of research because of sample heterogeneity, low surface concentrations, and the necessity of investigating the solid adsorbents in the presence of water. Unambiguous information can be obtained only with in situ surface spectroscopy, such as X-ray photoelectron (XPS), extended X-ray absorption fine structure (EXAFS), X-ray absorption near edge structure (XANES), inelastic electron tunnelling (lETS), and electron energy loss (EEL) spectroscopies. Recent advances in the development of non-invasive, in situ spectroscopic scanned-probe and microscopic techniques have been applied successfully to study mineral particles in aqueous suspensions (Hawthorne, 1988 Hochella and White, 1990 Bertsch and Hunter, 1998). 

For analysis, we used inelastic scattering cross sections calculated from REELS data. As already mentioned, this should, in principle, be superior to cross sections calculated from optical data because it also reproduces surface loss features such as surface plasmons. As the fine structure of K ( q, T) depends on the primary energy [108], we chose the energy of the primary electron beam to match the energy range of the Auger lines. In the subsequent analysis the depth profile in a first approximation was assumed to be a flat layer cut off at the characteristic depth of excitation dc... 

---