Synthesis and Crystal Structure of Rb6Ta4S22: The First Tantalum Polysulfide Composed of the Dimeric Complex Anion [Ta4S22]6– |
| |
Authors: | Petra Stoll,Christian Nä ther,Inke Jeß ,Wolfgang Bensch |
| |
Abstract: | The reaction of Rb2S3, Ta and S in a 1.3 : 1 : 5.6 molar ratio at 400 °C yields red‐orange crystals of the new ternary compound Rb6Ta4S22 being the first tantalum polysulfide containing the dimeric complex anion [Ta4S22]6–. The polysulfide anions are composed of two Ta2S11 subunits which are linked to Ta4S22 units via terminal sulfur ligands. The Ta5+ centers are coordinated by S22– and S2– ligands according to [(Ta2(μ2‐η2,η1‐S2)3(η2‐S2)(S)2)2(μ2‐η1,η1‐S2)]6–. Every Ta5+ ion is surrounded by seven sulfur ions forming a strongly distorted pentagonal bipyramid. In the crystal structure the discrete [Ta4S22]6– anions are stacked parallel to the crystallographic b‐axis. The Rb+ cations are located between these stacks. Rb6Ta4S22 crystallizes in the monoclinic space group P21/c (No. 14) with a = 11.8253(9) Å, b = 7.9665(4) Å, c = 19.174(2) Å, β = 104.215(9)°, V = 1751.0(2) Å3, Z = 2. |
| |
Keywords: | Tantalum polysulfides Crystal structure |
|
|