Solvothermal Synthesis, Crystal Structure Determination, and Properties of the Thioantimonate [Ph₄P]₂[Sb₆S₁₀]

Summary.

 The reaction of elemental antimony with elemental sulfur and [Ph₄P]Br in an aqueous solution of neopentanediamine under solvothermal conditions yields yellow needles of the new thioantimonate(III) [Ph₄P]₂[Sb₆S₁₀]. The structure consists of [Ph₄P]⁺ cations and infinite one-dimensional anionic (Sb₆S₁₀ ²⁻)_n chains running along the crystallographic a axis. The chains are composed of 10-membered Sb₅S₅ rings with alternating Sb and S atoms and separated by the tetraphenylphosphonium cations. Upon heating the compound decomposes in two distinct steps, starting at about 100°C. The final product was identified by X-ray powder diffractometry as Sb₂S₃.