Structural Investigations and Thermal Behaviour of Mercury(II) Sulfito Complexes

• Published in: Zeitschrift für anorganische und allgemeine Chemie (1950) 2007-03, Vol.633 (3), p.429-434
• Main Authors: Weil, Matthias, Breitinger, Dietrich K., Liehr, Günther, Zürbig, Jürgen
• Format: Article
• Language: English
• Subjects: Mercury; Structure elucidation; Sulfito ligands
• ISSN: 0044-2313; 1521-3749
• DOI: 10.1002/zaac.200600313

The crystal structures of (NH4)[HgSO3Cl] (1) and of (NH4)2[Hg(SO3)2] (2) were determined from single crystal diffractometer data sets. 1: 22 °C, Pnma, Z = 4, a = 15.430(3), b = 5.525(1), c = 6.679(1) Å, R(F) = 0.0256, Rw(F2) = 0.0642 (all 1056 unique reflections). 2: −108 °C, P212121, Z = 4, a = 6.2240(4), b = 9.3908(6), c = 13.6110(8) Å, R(F) = 0.0179, Rw(F2) = 0.0493 (all 2699 unique reflections). The structure of 1 contains bent Cl‐Hg‐SO3 entities (site symmetry m; d(Hg‐Cl) = 2.3403(13) Å, d(Hg‐S) = 2.3636(12) Å, ∠(Cl‐Hg‐S) = 164.51(5)°, d(S‐O) 2×1.458(3) Å, 1.468(4) Å, ${\bar d}\rm (S-O)$= 1.461Å) linked to undulated ribbons parallel to the b‐axis by intermolecular secondary bonds SO···Hg (d(O···Hg) = 2×2.595(3) Å). These ribbons in turn aggregate to layers around the bc‐plane. The layers are stacked along the a‐axis with interlayer distances of a/2. The structure of 2 is made up of O3S‐Hg‐SO3 moieties (d(Hg‐S) = 2.3935(7), 2.3935(8) Å; ∠(Hg‐S‐Hg) = 174.41(3)°; ${\bar d}\rm (S-O)$ = 1.474Å), that are linked to ribbons parallel to the a axis by coordination of Hg to three remote O atoms (2.801(4) < d(Hg‐O) < 2.844(3) Å). Adjacent ribbons are joined together by an additional Hg‐O contact of 2.733(3) Å, leading to a three‐dimensional anionic framework. Both crystal structures are stabilised by disordered NH4+ cations, placed between the anionic layers or in the vacancies of the framework, via moderate hydrogen bonding interactions N‐H···O with donor‐acceptor distances ranging from 2.8 to 3.2Å. 1 and 2 were further characterised by thermal analysis (TG, DSC). They start to decompose at temperatures above 130 °C.