The <i>h</i> -Sb <sub/>x</sub> WO <sub/> 3+2 <i>x</i> </sub> Oxygen Excess Antimony Tungsten Bronze

摘要： The previously unreported oxygen excess hexagonal antimony tungsten bronze is reported, with a composition of Sb0.5W3O10, in the following denoted as h-SbxWO3 + 2x with x = 0.167, to demonstrate its analogy to classical AxWO3 tungsten bronzes. This compound forms in a relatively narrow temperature range between 580 8C < T < 620 8C. It was obtained as a dark-blue polycrystalline powder, and as thin, needle-shaped, blue single crystals. h-SbxWO3 + 2x crystallizes in the hexagonal space group P6/mmm with the cell parameters a = 7.4369(4) (cid:2) and c = 3.7800(2) (cid:2). The antimony and excess oxygen occupy the hexagonal channels within the network of corner-sharing WO6 octahedra. h-SbxWO3 + 2x has a resistivity of 1300 K (cid:2) 1.28 mW cm at room temperature, with little if any temperature-dependence on cooling. DFT calculations on a simplified model for this compound find a metallic-like electronic structure with the Fermi level falling within rather flat bands, especially around the G point.