language: en

DOI: 10.1002/zaac.200700530

Well-Ordered Crystals of TaI 5 . The Formation of the Ternary Iodide CsTaI 6

Katja Habermehl a , Ingo Pantenburg a , Peter Held b , and Gerd Meyer a, *
Köln,
Institute für a Anorganische Chemie und b Kristallographie der Universität
Received November 26th, 2007.

Abstract. Well ordered single crystals of TaI 5 (orthorhombic, Pnma (no. 62), a = 1396.2(2), b = 2009.5(4), c = 660.7(1) pm, Z <U+6E129> 8, R 1 for 967 reflections with I 0 >2?(I 0 ): 0.0381) were obtained from a reaction of the elements. The structure determination confirms M�ller's prediction of 1978. Single crystals of CsTaI 6 (monoclinic, C2/c (no. 15), a = 1362.3(2), b <U+6E129> 709.9(1), c = 1736.2(3) pm, ? = 128.77(1)�, Z = 4, R 1 for 1140 reflections with I 0 >2?(I 0 ): 0.0378) were obtained by the oxidation of tantalum with CsI 3 . Both crystal structures contain [TaI 6 ] octahedra which are edge-connected to Ta 2 I 10 dimers in TaI 5 and isolated as [TaI 6 ] = anions in the salt Cs[TaI 6 ] (CsWCl 6 type of structure).

Keywords: Tantalum; Iodide; Crystal structure