Solvent-controlled assemblies, structures, and properties of two Hg(II) coordination polymers with a multidentate N-donor tecton 3,4-bis(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole

Coordination polymers [Hg(L-2)Cl-2](n) (1) and {[Hg-2(L-2)Cl-4](DMF)}(n) (2) have been assembled from Hg(II) chloride and a novel tripyridyltriazole tecton 3,4-bis(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L-2) in different solvent media. Both complexes have been characterized by IR, microanalysis, powder X-ray diffraction, and thermogravimetric analysis. Single crystal X-ray diffraction indicates that the L-2 ligands take the (eta(3), mu(2)) and (eta(4), mu(3)) binding modes in 1 and 2. respectively, which connect the Hg(II) centers to afford linear and ladder-like 1D arrays. Interestingly, complex 1 exhibits strong solid state fluorescent emission at room temperature due to the intraligand transitions, whereas complex 2 is non-fluorescent. (C) 2010 Elsevier B.V. All rights reserved.