A Lead Carboxylate-Azolate Metal-Organic Framework Based on Hexanuclear Clusters: Luminescence and Accelerating the Thermal Decomposition of Ammonium Perchlorate

A lead carboxylate-azolate framework, [Pb-3(mu(4)-O)(L)(2)(H2O)(2)H2O (1), has been constructed from the reaction of 2-methyl-4-(1H-tetrazol-5-yl) benzoic acid (H2L) and Pb(NO3)(2) under solvothermal conditions. Compound 1 contains an unprecedented hexanuclear cluster [Pb-6(mu(4)-O)(2)(COO)(4)(CN4)(2)], which as an 8-connected node is connected by 3-connected L linkers to give rise to a three-dimensional framework with an uncommon (3,8)-connected tfz-d; UO3 topology. Framework 1 possesses strong solid-state yellow luminescence (563 nm), which stems from ligand-to-metal charge transfer (LMCT), however, the removal of water molecules in 1 lead to the significant luminescent decrease of the sample. Importantly, in the presence of 1, the thermal decomposition of ammonium perchlorate is significantly accelerated.