Sn9 4– Zintl Ions as Reactive Precursor for Neat Solids: Syntheses and Crystal Structures of Rb4[SnTe4], KxCs4–x[SnTe4], and KxCs10–x[Sn4Te12]

Abstract

The reactions of Zintl ions Sn9 4− formed in ethylenediamine solutions of K2Cs2Sn9 and Rb4Sn9 with elemental tellurium have been investigated. Addition of elemental tellurium to the filtrates of these solutions leads - depending on the reaction conditions - to four different products: Compounds K0.36(1)Cs3.64(1)[SnTe4] (1) and Rb4[SnTe4] (2) contain the tetrahedral anion [SnTe4]4−, and Cs4[Sn2Te7] (3) features the anion [Te2Sn(μ-Te)(μ-Te2)SnTe2]4−, whereas a novel Zintl anion [Sn4Te12]10− is present in compound K0.44(1)Cs9.56(1)[Sn4Te12] (4). Compounds 1, 2 and 4 have been structurally characterized by single-crystal X-ray diffraction