@misc{PabstChangFinzeletal., author = {Pabst, Falk and Chang, Jen-Hui and Finzel, Kati and Kohout, Miroslav and Schmidt, Peer and Ruck, Michael}, title = {The Subbromide Bi5Br4 - On the Existence of a Hidden Phase}, series = {Zeitschrift f{\"u}r Anorganische und Allgemeine Chemie}, volume = {646}, journal = {Zeitschrift f{\"u}r Anorganische und Allgemeine Chemie}, number = {3}, doi = {10.1002/zaac.201800149}, pages = {149 -- 155}, abstract = {Black and irregularly shaped crystals of the bismuth-rich bromide Bi5Br4 were obtained as a by-product of the reaction of CsBr, Bi, and BiBr3. X-ray diffraction on a single-crystal revealed its orthorhombic structure with the space group Pmmn (no. 59) and lattice parameters a = 1800.0(2) pm, b = 1476.1(1) pm, and c = 924.5(2) pm at 296 K. The structure is composed of Bi82+ and Bi95+ polycations and bromidobismuthate(III) anions according to the structured formula Bi5Br4 = Bi20Br16 = Bi82+Bi95+[BiBr5]2-[Bi2Br11]5-. Bi5Br4 is the bismuth-richest among the bismuth subhalides containing isolated polycations. Extensive differential scanning calorimetry studies indicate that Bi5Br4 decomposes at 262 °C, i.e. one degree below the bismuth-rich eutectic at 263 °C. All attempts towards a rational synthesis yielded predominantly the neighboring phases BiBr and Bi6Br7.}, language = {en} }