[Li6(c2n2h8)11.5][fe4se8]: the First Lithium-Containing Chalcogenidotetraferrate Synthesized in Solution

The octaselenidotetraferrate(II/III) with six Li atoms as counter-ions chelated by ethylenediamine (en, C2H8N2), {[Li6(en)11.5][Fe4Se8]} n , was synthesized from Li, FeSe and Se in an ethylenediamine solution at room temperature. Its crystal structure was determined at 100 K and has triclinic (P\overline{1}) symmetry. The [Fe4Se8]6− anions show a connectivity comparable to a distorted tetrahedral cluster structure. Contact distances are given, and central structure features compared to literature known selenidoferrates with the same anion motif.