[Cs6Cl][Fe24Se26]: A Host–Guest Compound with Unique Fe–Se Topology. Issue 13 (16th February 2016)

• Record Type: Journal Article
• Authors: Valldor, Martin; Böhme, Bodo; Prots, Yurii; Borrmann, Horst; Adler, Peter; Schnelle, Walter; Watier, Yves; Kuo, Chang Yang; Pi, Tun‐Wen; Hu, Zhiwei; Felser, Claudia; Tjeng, Liu Hao
• Is Part Of: Chemistry. Volume 22:Issue 13(2016)
• Page Start: 4626
• Page End: 4631
• Publication Date: 2016-02-16
• Subjects: inorganic synthesis -- iron -- magnetic properties -- Mössbauer spectroscopy -- X-ray diffraction; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201504840
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The novel host–guest compound [Cs6 Cl][Fe24 Se26 ] ( I 4/ mmm ; a =11.0991(9), c =22.143(2) Å) was obtained by reacting Cs2 Se, CsCl, Fe, and Se in closed ampoules. This is the first member of a family of compounds with unique Fe–Se topology, which consists of edge‐sharing, extended fused cubane [Fe8 Se6 Se8/3 ] blocks that host a guest complex ion, [Cs6 Cl] 5+ . Thus Fe is tetrahedrally coordinated and divalent with strong exchange couplings, which results in an ordered antiferromagnetic state below T N =221 K. At low temperatures, a distribution of hyperfine fields in the Mössbauer spectra suggests a structural distortion or a complex spin structure. With its strong Fe–Se covalency, the compound is close to electronic itinerancy and is, therefore, prone to exhibit tunable properties. Abstract : Fused cubane : A unique Fe–Se lattice (see figure) hosts the complex ion [Cs6 Cl] 5+ . Tetrahedrally coordinated magnetic Fe 2+ ions, found in separated octamers, order antiferromagnetically below T N =221 K. Spectroscopic data suggest that this host–guest compound is close to electronic itinerancy.