Secondary bonding. Part 3. The crystal and molecular structure of tetramethylammonium µ-dimethylamino-bis(chloroiodate)(1–): a pseudopolyhalide

Abstract

The crystal structure of the title compound has been determined by the heavy-atom method at –60 °C from diffractometer data. The crystals are monoclinic, space group P2/c, with a= 11.233(3), b= 5.773 4(10), c= 11.087(2)Å, β= 98.24(2)°, Z= 4, and R= 0.063 for 1 056 reflections having (sin θ)/λ > 0.5. They contain [NMe₄]⁺ and [NMe₂(ICl)₂]^– ions. The latter can be considered as pseudopolyhalide ions, with [NMe₂]^– as a pseudohalide. In the anion, the nitrogen atoms are tetrahedral and N–I–Cl is linear [N–l 2.220(7). I–Cl 2.672(3)Å].