3-Ammonio-pyridinium tetra-bromido-mercurate(II) monohydrate

Abstract

The asymmetric unit of the title compound, (C5H8N2)[HgBr4]·H2O, consists of one cation, one anion and one water mol-ecule. The anion exhibits a distorted tetra-hedral arrangement about the Hg atom. The crystal structure contains alternating sheets of cations (in the ac plane) and stacks of anions. Several strong hydrogen-bonding inter-actions (pyN - H⋯Br and C - H⋯Br; py is pyridine), along with O - H⋯Br inter-actions, connect the sheets of cations to the stacks of anions. Cation-cation π-π stacking is also present (C⋯C distances in the range 3.424-3.865 Å). The shortest Br⋯Br distance is 3.9527 (9) Å.