PREPARATION OF HIGHLY ORDERED GdFe2 ALLOYS

The monolayer of the highly ordered GdFe 2 alloy was prepared on top of a W(110) substrate and characterized by using scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). The crystallographic arrangement of the ultrathin films does not coincide with the bulk structure (C15 Laves phase). This is due to the large misfit between the lattice constant of the Laves phase and the W(110) substrate. A structure model for the ultrathin GdFe 2 films on W(110) is proposed basing on atomically resolved STM images and LEED studies.