Syntheses, Structures, and Properties of New Quaternary Gold-Chalcogenides: K2Au2Ge2S6, K2Au2Sn2Se6, and Cs2Au2SnS4

✍ Scribed by Sandra Löken; Wolfgang Tremel

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: German
• Weight: 180 KB
• Volume: 624
• Category: Article
• ISSN: 0372-7874
• DOI: 10.1002/(sici)1521-3749(199810)624:10<1588::aid-zaac1588>3.0.co;2-x

✦ Synopsis

The new compounds K 2 Au 2 Ge 2 S 6 (1), K 2 Au 2 Sn 2 Se 6 (2), and Cs 2 Au 2 SnS 4 (3) have been synthesized through direct reaction of the elements with a molten polyalkalithiogermanate(stannate) flux at 650, 550, and 400 °C, respectively. Their crystal structures have been determined by single crystal X-ray diffraction techniques. 1 crystallizes in the monoclinic space group P2 1 /n with a = 10.633(2) A Ê , b = 11.127(2) A Ê , c = 11.303(2) A Ê , b = 115,37(3)°, V= 1208,2(3) A Ê 3 and Z = 4, final R(Rw) = 0.045(0.106). 2 crystallizes in the tetragonal space group P4/mcc with a = 8.251(1) A Ê , c = 19.961(4) A Ê , V = 1358,9(4) A Ê 3 and Z = 4, final R(Rw) = 0.040(0.076). 3 crystallizes in the orthorhombic space group Fddd with a = 6.143(1) A Ê , b = 14.296(3) A Ê , c = 24.578(5) A Ê , V = 2158.4(7) A Ê 3 and Z = 4, final R(Rw) = 0.039(0.095). The structures of 1, 2, and 3 consist of infinite, one-dimensional anionic chains containing X 2 Q 6 4± units linked by Au + ions and charge balancing K + /Cs + ions situated between the chains. All compounds were investigated with differential thermal analysis, FT-IR, and solid state UV/ VIS diffuse reflectance spectroscopy.