Solid chemistry of the ZnII/1,2,4-triazolate/anion system: Separation of 2D isoreticular layers tuned by the terminal counteranions X (X = Cl-, Br-, I-, SCN-)

An array of 2D isoreticular layers, viz. [Zn(atrz)X](infinity) (1-X; X = Cl-, Br-, I-; atrz = 3-amino-1,2.4-triazole anion), [Zn-4(atrz)(4)(SCN)(4) center dot H2O](infinity) (1 center dot SCN center dot H2O) and [Zn(trz)X](infinity) (2 center dot X; X = Cl-, Br-, I-; trz = 1.2,4-triazole anion), have been hydrothermally synthesized and structurally characterized. Compounds 1 center dot X and 1 center dot SCN center dot H2O are constructed from binuclear planar Zn-2(atrz)(2) subunits and exhibit (4,4) topological network when the Subunits are simplified as four-connected nodes. Based on changing the terminal counteranions X (X = Cl-, Br-, I-, SCN-), the average interlayer separations of 1 center dot X and 1 center dot SCN center dot H2O are enlarged, which equal to 5.851, 6.153, 6.651 and 8.292 angstrom. respectively. As a result, H2O molecules reside in the spaces between two adjacent layers of 1 center dot SCN center dot H2O. 2 and 1 are the isomorphous structures. In common with 1, the interlayeF separations of 2 - X are widened with increasing the ion radius. Solid-state luminescence properties and thermogravimetric analyses of I and 2 were investigated, respectively. (C) 2008 Elsevier Inc. All rights reserved.