Polycationic Hg-As frameworks with trapped anions.: II -: [1] Synthesis, crystal structure, and magnetism of (Hg6As4)[MoCl6]Cl, (Hg6As4)[TiCl6]Cl, and (Hg6As4)[TiBr6]Br

(Hg6As4)[MoCl6]Cl is obtained by reaction of Hg2Cl2, Hg, As, and MoCl4 in closed, evacuated glass ampoules in a temperature gradient 450 --> 400 degrees C in form of dark red cubelike crystals. (Hg6As4)[TiCl6]Cl and (Hg(6)AS(4))-[TiBr6]Br are also formed in closed, evacuated ampoules from Hg2X2 (X = Cl, Br), Hg, As, and Ti metal at 275 degrees C and 245 degrees C in form of dark green and black crystals, respectively All three compounds are air and light sensitive. They crystallize isotypically (cubic Pa (3) over bar, a = 1207.8(4) pm for (Hg6As4)- [MoCl6]Cl, a = 1209.4(3) pm for (Hg6As4)[TiCl6]Cl, a = 1230.9(3) pm for (Hg6As4)[TiBr6]Br, Z = 4). The structures consist of a three-dimensionally connected Hg-As framework which is made up of As-2 groups (As-As distance averaged 242 pm) each connected via six Hg atoms to six neighbouring As-2 groups. There are two cavities of different size in the polycationic framework. The bigger cavity is filled with [MoCl6](3-), [TiCl6](3-), and [TiBr6](3-) ions of nearly ideal octahedral shape, the smaller cavity with discrete balide ions. The magnetic properties of the two Ti containing compounds are in accordance with a dl paramagnetism. The temperature dependence and the magnitude of the magnetic moment can be interpreted with consideration of the spin-orbit coupling. The so far known representatives of this structure type can be characterised by the ionic formula (Hg6Y4)(4-)[MX6]X-3-(-) (Y = As, Sb; M = Sb3+, Bi3+, Mo3+, Ti3+; X = Cl, Br).