computer simulations of ion scattering spectra for 2.4 keV Ne+ incident on Ni(001)

Monte-Carlo computer simulations of Buck's Time-of-Flight Ion Scattering Spectroscopy data collected for 2.4 keV Ne⁺ incident on a Ni (001) surface were used to examine the importance of various input parameters in the computational model. The binary collision approximation was found to yield satisfactory results for this particular projectile, energy, and target. The calculated energy spectra were quite sensitive to the screening length of the Molière potential used for calculating the binary collision interactions and to the magnitude of the mean square vibrational amplitudes chosen for the Ni atoms in the lattice. The agreement between the calculated and experimental spectra was good, but the calculations probably could have been improved a little further by fine tuning the parameters in the simulation. The simulations showed that the ISS spectra for 2.4 keV Ne⁺ ion beam incidence directions along the 110] azimuth of Ni(001) were dominated by multiple scattering events and that the second layer of the surface contributed most to the backscattering because of the focusing effect of the first layer atoms.