Isomer dependent assembly of Ce(III) and Gd(III) coordination polymers containing 5-(n-pyridyl)tetrazole-2-acetato (n=3,4)

Isomer plays a vital role in the self assembly process of the coordination compounds. Tetrazole-carboxylate ligands with rich nitrogen and oxygen atoms are excellent candidates for the construction of novel coordination architectures. 5-(n-pyridyl) tetrazole-2-acetato potassium salt (denoted as Kn-pytza, n = 3,4) was selected to be reacted with LnCl(3)center dot 6H(2)O (Ln = Ce, Gd), resulting in the formation of [Ln(3-pytza)(2)Cl(H2O)(2)] n [Ln = Ce(1), Gd(2)] and [Ln(4-pytza)(3)(H2O)(2)](n)center dot 2nH(2)O [Ln = Ce(3), Gd(4)], respectively. The X-ray diffraction analysis reveals that compounds 1 and 2 are similar with one dimensional zigzag chains while compounds 3 and 4 are isomorphic with one dimensional ladder-like chains consisting of Ln(2)O(6) (Ln = Ce, Gd) secondary building units (SBU) and the bridging 4-pytza, which can be attributed to the different coordination modes adopted by the isomeric ligands. In addition, the photoluminescence properties of the ligands and compounds 1-4 in the solid state were investigated at room temperature. (C) 2016 Elsevier B.V. All rights reserved.