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Herein, we report the design and crystal growth of the network of K2H2mpba (1) [H4mpba = N,N′-1,3-phenylenebis(oxamic acid)], which exhibits the quite unusual (6,12)-connected alb topology. The characterization of 1 shows the following features: (i) the presence of deprotonated H2mpba2− moieties, (ii) thermal stability up to approximately 300 °C, and (iii) H2mpba2− acting as a 12-c molecular building block (MBB) and occupying the vertices of the double six-membered ring "d6R". These rings combine with potassium ions, which fill the vertices of a trigonal prism. A discussion is provided on the role played by the type of metal centre (Mn+, M = Mn, Ni, Co, Cu) and countercation [tetrabutylammonium (TBA+) or tetraethylammonium (TEA+)] in a series of structurally characterized Mn+–H2mpba2− systems described in the literature. [ABSTRACT FROM AUTHOR]

We present a highly photoluminescent and thermally stable terbium(III) coordination network [TbHbtec] n CN 1 , exhibiting a cubic primitive network with topology pcu - α Po, uninodal and point symbol (412. 63). The results show that CN 1 is a good candidate for luminescent marker of gunshot residues (GSR). • New TbIII-coordination network with topology pcu - α Po uninodal and point symbol (412. 63). • 3-D coordination network of formula [TbHbtec] n , [H 4 btec = 1,2,4,5-benzenetetracarboxylic acid]. • High thermal stability (higher than 470 °C) and high photoluminescence. • Good candidate as luminescent marker for gunshot residues. • Stability of the structure after exposure to high temperature of detonation. A novel terbium(III) coordination network (CN) of formula [TbHbtec] n 1 , constructed from 1,2,4,5-benzenetetracarboxylic acid (H 4 Btec) and Tb3+ ions, has been obtained under hydrothermal conditions. Single crystal X-ray diffraction and topological studies revealed the crystal structure of CN 1 involves a cubic primitive network with topology pcu - α Po, uninodal and with point symbol (412. 63). In the crystal structure, the ligand is monoprotonated (Hbtec3−) with six Hbtec3− adopting the monodentate, bidentate chelating and bidentate chelating-bridging coordination modes, leading to the formation of a 3-D coordination network. Solid state luminescence spectrum showed the characteristic 5D 4 → 7F J (J = 6–2) transitions of the Tb3+ ion upon excitation in the Hbtec3− singlet levels, revealing that the ligand Hbtec3− is a good sensitizer for the intense green emission of Tb3+ ions. Thermogravimetric analysis (TGA) showed CN 1 has exceptional thermal stability decomposing at temperatures higher than 470 °C. Taking advantage of its excellent thermal and optical properties, the [TbHbtec] n was tested as luminescent marker for gunshot residues, opening the possibility of using this compound in forensic analysis of crime scenes. [ABSTRACT FROM AUTHOR]