[C6H21N4][Sb9S14O]: Solvothermal synthesis, crystal structure and characterization of the first non-centro symmetric open Sb-S-O framework containing the new [SbS2O] building unit

摘要

[C6H21N4][Sb9S14O] represents the first known oxo-thioantimonate with an organic ion acting as structure director. The compound 3 crystallizes in the non-centrosymmetric space group Cmc2(1) with a = 29.679(2), b = 9.9798(6), c = 11.7155(7) angstrom, V = 3470.1(4) angstrom(3) Z = 4. The structure contains the hitherto unknown [SbS2O] unit as a structural motif. The [SbS3] trigonal pyramids and [SbS2O] units are joined to form a 10-membered ring with large pores having a diameter of 7.7 angstrom x 8.3 angstrom. The organic template molecule acts like a tetra-dentate ligand around the O atom of the [SbS2O] group. Depending on the value chosen for the Sb-S bond lengths, the material contains a 1-, 2- or 3-dimensional anion. The optical band gap of 2.03 eV demonstrates that the material is an optical semi-conductor. Upon heating, the compound decomposes in two steps yielding finally a mixture of Sb and Sb2S3. The Sb-121 Mossbauer spectrum shows a relative large line width in accordance with the superposition of the five signals. (c) 2006 Elsevier Inc. All rights reserved.