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

•K3-pytza and K4-pytza and their Ce(III) and Gd(III) compounds were prepared.•Isomer determines the coordination modes of such ligands.•The luminescence were investigated.

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 LnCl3·6H2O (Ln = Ce, Gd), resulting in the formation of [Ln(3-pytza)2Cl(H2O)2]n [Ln = Ce(1), Gd(2)] and [Ln(4-pytza)3(H2O)2]n·2nH2O [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 Ln2O6 (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.

Graphical abstractFour new Ce3+/Gd3+ compounds based on isomeric 5-(n-pyridyl)tetrazole-2-acetato potassium salt (n = 3,4) were prepared. The structural variation was assigned to the different coordination mode of the isomers. The luminescence properties were investigated.Figure optionsDownload full-size imageDownload as PowerPoint slide