Abstract: | PPh4As3S3Cl4] and PPh4As3S3Br4] When As2S3 reacts with PPh4X and HX in 1,2-C2H4X2 (X = Cl, Br), the title compounds are obtained as minor products; the main products are PPh4As2SX5]. Their crystal structures were determined by X-ray diffraction. PPh4As3S3Cl4]: a = 1187.7, b = 1090.9, c = 1191.8 pm, α = 82.91, β = 88,93, γ = 88.52°; twins with twin plane (100); R = 0.109 for 1618 observed reflexions of one twin crystal. PPh4As3S3Br4]: a = 1119.7, b = 1177.5, c = 1204.1 pm, α = 81.59, β = 85.88, γ = 88.25°; R = 0.061 for 2331 observed reflexions. Both compounds crystallize in the space group P1 , Z = 2, and can be considered to be isotypic. Nevertheless, PPh4As3S3Br4] does not form twins as PPh4As3S3Cl4]. The crystals consist of PPh4+ and As3S3X4]? ions. In the anions, the three As atoms of an As3S3 ring in the chair conformation are commonly joined to an X atom and each As atom is bonded to one further terminal X atom. Cations and anions are packed in alternating layers. |