Different water clusters dependent on long-chain dicarboxylates in two Ag(I) coordination polymers: Synthesis, structure and thermal stability

Abstract

Two mixed-ligand Ag(I) coordination polymers (CPs), [Ag(2)(bipy)(2)(sub)center dot 5H(2)O](n) (1). [Ag(2)(bipy)(2)(aze)center dot 3H(2)O](n), (2), (bipy = 4,4'-bipyridine, H(2)sub = suberic acid, H(2)aze = azelaic acid) have been synthesized and structurally characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis, and single crystal X-ray diffraction. Both 1 and 2 are two-dimensional (2D) sheets based on infinite [Ag(bipy)](n) double chain incorporating Ag center dot center dot center dot Ag interactions. Interestingly, two different water clusters are encapsulated in the voids between the sheets of 1 and 2. For 1, one water decamer (H(2)O)(10) based on a cyclic water tetramer was hydrogen-bonded with the host 2D sheet. While, one water hexamer (H(2)O)(6) also based on a cyclic water tetramer was observed in 2. Comparing the experimental results, it is comprehensible that the dicarboxylates play a crucial role in the formation of the different water clusters. Moreover, the thermal stabilities of them were also discussed. (C) 2011 Elsevier B.V. All rights reserved.