CRYSTAL-STRUCTURES OF THE SUPRAMOLECULAR 1,4-DIAZABICYCLO[2.2.2]OCTANE MERCURY(II) COMPLEXES [HG(DABCO)I-2] AND [HG(DABCO)(SCN)(2)]

Reactions of 1,4-diazabicyclo[2.2.2]octane (''dabco'') with K-2[HgI4] Or Hg(SCN)(2) yield crystals of [Hg(dabco)I-2] (1) and [Hg(dabco)(SCN) (2)] (2). 1 crystallizes monoclinically, space group P2(1)/a, Z = 4, a = 1211.6(5), b = 682.3(6), c = 1430.4(3) pm, beta = 98.90(5)degrees; 2 is orthorhombic, space group Pmmn, Z = 2, a = 740.5(3), b = 609.1(4) , c = 1220.0(8) pm. In 1 HgI2 groups are connected by bridging dabco m olecules to give a chain structure. The Hg atoms are tetrahedrally coo rdinated. In 2 the Hg atoms are bridged by two SCN ligands and the cha ins thus formed are again interconnected by bridging dabco molecules, whereby layers are formed. The coordination polyhedron for the Hg atom s is a distorted octahedron.