Two new metal–triazole-benzenedicarboxylate frameworks affording an uncommon 3,4-connected net and unique 4,6-connected rod packing: hydrothermal synthesis, structure, thermostability and luminescence studies

Abstract

Two new metal–triazole-benzenedicarboxylate coordination polymers are obtained by the hydrothermal self-assembly of Zn(or Cd)(NO3)2, trz, and 1,3-H2BDC(or 1,4-H2BDC), where trz and BDC are triazole and benzenedicarboxylate. Polymer 1, Zn(trz)(1,3-HBDC), crystallizes in the P21/c space group and shows the 2D fes 4·82 net, which is further extended via strong O–H⋯O/2.641 A hydrogen bonds, creating the supramolecular 3,4-connected net described by (4·82)(4·82·103) Schlafli symbol. Polymer 2, Cd4(H2O)2 (trz)2(1,4-BDC)3·H2O, have the C2/c space group and complicated 3D architecture, an architecture that is comprised of two distinct rod-like substructures, viz. 4-connected {Cd(trz)(H2O)(CO2)}n of corner-sharing octahedra and 6-connected {Cd(trz)(CO2)}n of edge-sharing octahedra. In the solid, both 1 and 2 have strong luminescence, viz. 453 nm for 1 and 398 nm for 2, which suggests the potential luminescence material of 1 and 2.