Two 3D photoluminescent Zn(ii) complexes constructed from 5-amino-1-H-tetrazole with aromatic polycarboxylate ligands

Abstract

Two new Zn(II) complexes, namely, [Zn₂(BTEC)_0.5(ATZ)₂(H₂O)₃]·H₂O (1) and [Zn_1.5(2,5-PYDC)(ATZ)(H₂O)]₂ (2) have been assembled from 5-amino-1-H-tetrazole (HATZ) with two aromatic polycarboxylate ligands under hydrothermal conditions (H₄BTEC = 1,2,4,5-benzenetetracarboxylic acid, 2,5-PYDC = 2,5-pyridinedicarboxylic acid). Single crystal X-ray analysis reveals that both complexes display three-dimensional (3D) structures. Complex 1 is a binodal (4,4)-connected bbf net with a (6⁴·8²)(6⁶)₂ topological symbol. Complex 2 displays a trinodal (3,3,4)-connected net with (4·10²)₂(10²·12)₂(4²·10²·12²) topology. In the two structures, all the HATZ ligands are deprotonated and act as the anions, and the ATZ⁻ anions all connected two Zn(II) centers with a μ₂-mode. In addition, the two complexes display photoluminescence at 442 nm (λ_ex = 342 nm) and 468 nm (λ_ex = 374 nm), respectively. And their thermal stability has also been studied.