A family of Zn(ii)/Cd(ii) halide systems incorporating 5,5′-di(pyridin-2-yl)-3,3′-bi(1,2,4-triazole)

Abstract

By using 5,5′-di(pyridin-2-yl)-3,3′-bi(1,2,4-triazole) (2,2′-H₂dbpt) as a building block, six new coordination complexes: Zn₃(2,2′-Hdbpt)₂(H₂O)Cl₄ (1), {[Zn₂(2,2′-dbpt)Cl₃]·Et₃NH}_n (2), {[Cd₃Cl₃(2,2′-dbpt)₃]·2H₂O}_n (3), {[Cd₃I₃(2,2′-dbpt)₃]·H₂O}_n (4), {[Cd₂Br₂(2,2′-dbpt)]·H₂O}_n (5), and [Cd₂I₄(2,2′-H₂dbpt)]_n (6), based on the M(II)/X (M = Zn, Cd; X = Cl, Br, I) system were generated. 1 and 2 bear a Zn₃ supermolecule and a 1D wave-like chain, respectively. 3 and 4 are isostructural, giving a new 3D architecture with a (4¹²·6³) topology based on the [Cd₆] ring as a node bridged by the μ₂-Cl⁻ ion and the μ₂-I⁻ ion, respectively. 5 is a 2D framework with a (3²·6²·7²) topology based on the [Cd₄] subunit. 6 reveals a 1D modified trapezoid chain with a (4²·6) topology based on the trans-bridging 2,2′-H₂dbpt. Based on the interesting structural results, the solid-state luminescence properties of complexes 1–6 were investigated, which revealed that the emission maximum wavelengths can be tuned in a large range of 403–498 nm. These results indicate that 2,2′-H₂dbpt is not only an excellent building block to construct coordination complexes with interesting structures but also a good precursor to construct potential photoactive materials.