New Layered Iron‐Lanthanum‐Oxide‐Sulfide and ‐Selenide Phases: Fe2La2O3E2(E = S,Se)

A two-dimensional network of face-sharing FeO2E4 octahedrons (E = S, Se) interspersed with double layers of square E4O4 antiprisms, in whose centers lanthanum atoms are situated, is one description of the layers in the unusual structure of the Fe2La2O3E2 phases (see structure for E = Se on the right). Both the oxidesulfide and the oxideselenide are semiconductors with interesting magnetic properties.