Synthesis and characterization of K₅Sn₂OF₁₁

Abstract

The potassium oxidofluoridostannate(IV) fluoride K5Sn2OF11 was synthesized via a solid-state route at T = 300°C in arc-weldeded copper ampoules. It crystallizes in the orthorhombic system in the acentric space group Ama2 (no. 40) with a unit cell volume of V = 2.5727(4) nm3. The cell parameters are a = 1758.3(2), b = 2452.3(2) and c = 596.7(1) pm. As a main structural motif, K5Sn2OF11 exhibits two different kinds of dinuclear [Sn2OF11]5‒ units, which are embedded into a matrix consisting of potassium cations and fluoride anions. The substance was characterized by single-crystal and powder X-ray diffraction, as well as by FT-IR spectroscopy.

K2SnOF4 and K2WO3F2 – different but similar

“…Within this octahedron, the Sn-F bond lengths are 201.0(1) and 202.1(1) pm for Sn1-F1 and Sn1-F2, respectively, whereas the Sn-O bond length is 196.7(1) pm (Table S3; Supporting Information). These bond lengths are in accordance to the ones reported in the literature for K [19]. The bond angles confirm an octahedral coordination sphere (Table S4; Supporting Information).…”

“…Only the [SnOF 5 ] 3− unit has been reported in the literature. It has been observed in the structure of K 5 Sn 2 OF 11 [19], where this unit forms quasi-isolated dinuclear motifs. [19].…”

“…It has been observed in the structure of K 5 Sn 2 OF 11 [19], where this unit forms quasi-isolated dinuclear motifs. [19]. Even though the [SnO 2 F 4 ] 4− unit was predicted for the compound K 2 SnOF 4 by Kolditz and Preiss, this assumption has not yet been confirmed [20].…”