Polymeric mu-bromo-mu-pyridine-3-carboxylato-kappa3O,O':N-mercury(II)

Acta Crystallogr C. 2003 May;59(Pt 5):m165-7. doi: 10.1107/s0108270103005705. Epub 2003 Apr 10.

Abstract

The asymmetric unit of the title polymeric complex, [HgBr(C(6)H(4)NO(2))](n) or HgBr(nic), contains mercury coordinated via two Br atoms [Hg-Br = 2.6528 (9) and 2.6468 (9) A], two carboxylate O atoms, which form a characteristic four-membered chelate ring [Hg-O = 2.353 (6) and 2.478 (7) A], and an N atom [Hg-N = 2.265 (5) A], in the form of a very irregular (3+2)-coordination polyhedron. The pronounced irregularity of the effective Hg (3+2)-coordination is a result of the rigid stereochemistry of the nicotinate ligand. According to the covalent and van der Waals radii criteria, the strongest bonds are Hg-Br and Hg-N. These covalent interactions form a two-dimensional polymer. The puckered planes are connected by van der Waals interactions, and there are only two intermolecular C-H...O hydrogen bonds [3.428 (10) and 3.170 (10) A].