Leed and electron energy loss measurements of iron deposited on Ni(100)

Abstract

The adsorption and growth of iron on Ni(100) has been studied using the combined techniques of Low Energy Electron Diffraction (LEED) and Electron Energy Loss Spectroscopy (EELS). Initially iron grows by a layer-by-layer mechanism for the first few layers. In this stage of growth, fcc iron is produced. High iron coverages result in the observation of complex LEED patterns with satellites around the main (1 × 1) diffraction spots. This is due to the formation of bcc Fe(110) crystallites arranged in domains with different orientations. The presence of fcc iron crystallites was also inferred for the thick films. EELS studies show the presence of three stages in the growth of iron on Ni(100): low-coverage, film-like and bulk-like. The changes in the EELS spectra of the FeNi(100) system with iron coverage are used to re-interpret some of the electron energy loss peaks of nickel and iron. The 9.7 eV peak of clean nickel is believed to be due to interband transitions while the 27.3 eV peak is identified as volume plasmons, as is the peak at 16.3 eV of iron.