Synthesis and structure of an aryl-tellurenium(II) cation; [4-tert-butyl-2,6-bis-(1-pentyl-1H-benz-imidazol-2-yl-κN(3))phenyl-κC(1)]tellurium(II) (1,4-dioxane)tri-iodido-mercurate(II).

In the title salt, (C(34)H(41)N(4)Te)[HgI(3)(C(4)H(8)O(2))], the aryl-tellurenium [C(34)H(41)N(4)Te](+) cations and [HgI(3)(dioxane)](-) anions are linked by a short inter-action between the Te atom and one of the I-atom donors of the anion, as well as through weak C-H⋯I inter-actions. The geometry around the Te atom is T-shaped with the coordination comprising a C atom of the central aromatic ring and two N atom donors of the benzimidazolyl moiety. The Te-N bond lengths are almost equal [2.232†(3) and 2.244†(3)†à ], while the Te-C bond length is 2.071†(4)†à . The N-Te-N bond angle is 150.68†(11)°. The Hg(II) atom of the anion is coordinated by iodide ions from three sides and the fourth coordination site is occupied by an O atom of the solvent mol-ecule (dioxane). Thus, it attains a trigonal-pyrimidal geometry, with O-Hg-I angles ranging of 90.76†(8) and 96.76†(7)° and I-Hg-I angles ranging from 112.41†(1) to 125.10†(1)°. The cations and anions are involved in numerous weak π-π stacking inter-actions involving both the central phenyl ring and two inversion-related benzimidazole moieties, which propagate in the a-axis direction. In addition, there are numerous C-H⋯I inter-actions between the cations and anions, which link them into a complex three-dimensional array.