Crystal Engineering with Mercuric Chloride

摘要

Two new network solids containing mercury ions are reported. The structure of HgCl_4·H_2tpt·H_2O (tpt = 1,3,5-tri(4-pyridyl)-2,4,6-triazine) contains H_2tpt~(2+) cations connected into 1D zigzag chains via hydrogen bonding between protonated and unprotonated pyridyl groups of adjacent cations. The third pyridyl group of each H_2tpt~(2+) cation is also protonated and hydrogen-bonds to tetrahedral HgCl_4~(2-) anions that lie as appendages to the main hydrogen-bonded chain. (HgCl_2)_2(hmt) (hmt = hexamethylenetetramine) contains HgCl_2 and hmt molecules. The mercury is pseudo-octahedral, coordinating to two trans chloride ligands (Hg-Cl = 2.351(1) A) and making four much longer equatorial interactions with hmt molecules (Hg-N = 2.735(4) A) and adjoining HgCl_2 molecules (Hg-Cl = 3.105(1)A). The long Hg-N interactions link the two species into 2D (4,4) sheets, while long Hg-Cl interactions connect these sheets into an overall 3D network through chains of rhombohedral Hg-Cl…Hg-Cl… motifs.