Das Zustandsdiagramm Thallium(I)iodid-Thallium(I)selenid und die Kristallslruktur der Verbindungsklasse Tl6X4Y/The System Thallous Iodide -Thallous Selenide and the Structure of the Tl6X4Y Compounds

Abstract

Abstract The system TlI-Tl2Se was investigated by DTA, X-ray and metallographic methods. At the Tl2Se corner of the system a solid solution up to 25 mol% TlI is observed, which decomposes peritectically at 681 K. Two new compounds Tl5ISe2 and Tl6I4Se were found. The latter is isotypic to a class of compounds found in the TlX-TI2S systems [2]. The crystal structure of Tl6Cl4S was determined. It is based on the TlCl structure (CsCl-type) in which 1/5 of the Tl or Cl atoms, resp., are substituted by Tl2S in a regular manner. The coordination of the anions (Cl, S) is very similar to the coordination of Cl in TlCl or S in Tl2S resp.