Interplay of Electronic and Geometric Structure in a Model System: Epitaxial Iron Silicides

In this article, the interplay between electronic and geometric properties in transition metal silicide systems is presented using as a model system Fe–Si binary compounds. When iron silicides are epitaxially grown on Si(111), several different phases can be obtained, depending on the preparation conditions. In particular, for a 1:1 Fe:Si stoichiometry, there are two different phases possible: FeSi(CsCl) and ∊-FeSi. The former is a metastable phase, stabilized through epitaxy, while the latter is the bulk-stable phase for a 1:1 composition. Although the two have nominally the same composition, their different structures give rise to distinct electronic properties in each material. Their electronic structures have been probed by angle-resolved photoemission. In this article the results of this analysis will be presented along with the main properties of both compounds