Komplexbildung in TlCl3- und Chlorothallat(III)-Schmelzen / Complexation in TlCl3 and Chlorothallate(III) Melt Systems

Abstract

TlCl3 and TlCl3-TlCl mixtures have been prepared and investigated by Raman spectroscopy in the solid and molten state. Already at 50°C TlCl3 starts to decompose according to TlCl3 → TlCl + Cl2. TlCl generated reacts with TlCl3 to give TlCl4 -, Tl2Cl7~ and possibly Tln IIICl3n+1 - units with n ≧ 2, respectively. Molten TlCl3, can be described best by the equilibrium TlCl4 - + TlCl3 ⇄ Tl2Cl7 -. In solid TlCl3-TlCl mixtures the following species could be identified Tl3(TlIIICl6), Tl3 1(Tl2 IIICl9) and TlCl4). TlCl4 - and TlCl5 2- complex units dominate in the molten state. In the melt, species are in dynamic coupled equilibria depending on temperature and stoichiometry.