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Three MnII complexes, named Mn2(HATNA)2(CH3OH)4 (1), {[Mn3(ATNA)2(DMF)2(H2O)2]·0.5DMF·0.5H2O}n (2, DMF = N,N-dimethylformamide), and {[Mn6(ATNA)4(H2O)10]·8DMSO·2.5H2O}n (3, DMSO = dimethyl sulphoxide), were successfully synthesized by the reaction of the ligand azotetrazole-3-hydroxy-2-naphthoic acid (H3ATNA) and Mn(CH3COO)2 in CH3OH, DMF, and DMSO, respectively. A binuclear structure was found for complex 1, with the two Mn(II) ions doubly bridged through N–N linkers from the two tetrazole rings. Both 2 and 3 displayed one-dimensional structures. Magnetic studies show that antiferromagnetic interactions of Mn(II) ions existed in complexes 1–3. All the complexes exhibited luminescence emission peaks at room temperature. [ABSTRACT FROM AUTHOR]

A new compound of azotetrazole-3-hydroxy-2-naphthoic acid (H3ATNA) has been successfully synthesized and characterized. By controlling the ratio of metal ions to the ligand and the pH value of solution, mononuclear, dinuclear and tetranuclear dysprosium(III) complexes [Et3NH]3[Dy(HATNA)3]·5H2O (1), [Dy2(HATNA)3(DMF)(H2O)]·2DMF·CH3OH·2H2O (2) and [Et3NH]6[Dy4(ATNA)6(H2O)2]·DMF·2CH3CN·8H2O (3) were synthesized and characterized by X-ray diffraction crystallography (DMF = N,N-dimethylformamide). Crystallographic data demonstrate that the neutral H3ATNA exists as a hydrazone tautomer. Complex 1 is a mononuclear structure, in which the Dy(III) ion is a nine-coordinated ion surrounded by three tridentate HATNA− ligands. Complex 2 shows a dinuclear structure, which is bridged by three μ1,1-hydroxyl groups of three HATNA− ligands. In complex 2, the Dy(III)1 ion is a nine-coordinated ion surrounded by three tridentate HATNA− ligands, while Dy(III)2 is an eight coordinated atom with three tridentate HATNA− ligands, one DMF and one water molecule. Complex 3 displays a tetranuclear structure, which can be approximately considered as two μ1,3-carboxyl groups of ATNA3− ligands linking complex 2. The magnetic properties of 1–3 were investigated. Complexes 2 and 3 display slow magnetic relaxation in a zero dc field. [ABSTRACT FROM AUTHOR]

Energetic metal organic frameworks (EMOFs) are increasingly developed and have proven to be candidates for novel high energy density materials (HEDM). Here, two energetic metal complexes based on 3,5-diaminopyrazolone-4-oxime (DAPO) ligands were synthesized by simple steps and fully characterized by NMR and IR spectroscopy, X-ray single-crystal diffraction, and DSC-TG. The detonation performance was calculated using the Kamlet–Jacobs formula. The crystal densities of these complexes (C6H14N12O10Co (2) and C6H14N12O10Cd (3) are as high as 1.945 g cm−3 at 163 K and 2.072 g cm−3 at 298 K, respectively. Thermal analysis by the DSC-TG test shows that they all have good thermal stability with the highest decomposition temperatures of 287 °C and 344 °C, respectively. These two as-synthesized complexes exhibit excellent detonation performance; 2 (D = 8682 m s−1, P = 34.98 GPa) and 3 (D = 8383 m s−1, P = 33.78 GPa) have good detonation velocity and detonation pressure that are superior to those of TNT, which is widely used today. Thus, they show great promise for potential applications as thermally stable energetic materials. [ABSTRACT FROM AUTHOR]

Guided by synthetic chemistry, coordination chemistry and crystallization chemistry, a novel synthesis and crystallization strategy for laser complex energetic materials has been established in this study. In this study, a method with milder reaction conditions was adopted to design the steps and successfully synthesize urazine (H2ur). At the same time, using H2ur as the ligand, the "acid-controlled dissolution-crystallization" method was used to successfully prepare the crystalline coordination polymer Ag(H2ur)NO3 (5), and its 1D structure was confirmed by X-ray single crystal diffraction. The physicochemical property evaluation revealed that 5 has the best performance: insensitive to light, noncorrosive properties to metal shells, excellent tolerance to moisture, good thermal stability, and insensitive to mechanical stimulation. Theoretical calculations show that the compound has acceptable detonation properties (D = 7.6 km s−1, P = 31.83 GPa). In addition, hot-needle experiments show that 5 has a good DDT effect. More importantly, it has great potential for application in laser energetic materials (τ = 300 ms, E = 800 mJ). [ABSTRACT FROM AUTHOR]

Six 3,3′-azobis-1,2,4-triazole (H2ABT) complexes [Mn2 (ABT)(bpy)4(H2O)2]·(ABT)·4H2O (1), [Mn(ABT)(H2O)4]·H2O (2), [Co(ABT)(en)2]·(H2ABT)·2H2O (3), [Cd(ABT)0.5(en)2]·(ABT)0.5·2H2O (4), [Zn(ABT)0.5(en)2]·(ABT)0.5·2H2O (5), [Cu(ABT)0.5(en)2]·(ABT)0.5 (6), where en = ethylenediamine, bpy = 2,2-bipyridine, have been synthesized and characterized by single crystal X-ray diffraction analysis. In complexes 1–6, the unusual face-to-face π–π stacking interactions among heterocyclic aromatic rings and three kinds of hydrogen bonds C–H…O, N–H…O and O–H…O are observed. The π–π stacking, hydrogen bonding and electrostatic interactions are responsible for the stabilization of these 2D and 3D supramolecular structures. The aqueous solutions of 1–6 with the concentration of 6 × 10−5 mol dm−3 show photochromism. The fluorescent properties of solid-state samples of 1–6 have been investigated. The π–π stacking interaction energies for 1–6 were calculated at MP2 level using Gaussian 09 suite and demonstrated. [ABSTRACT FROM AUTHOR]

Two new MnII supramolecular isomers, [Mn2(pbt)2(H2O)2·2H2O]n (1) and [Mn2(pbt)2(H2O)2·DMF]n (2) (H2pbt = 5′-(pyridin-2-yl)-2H,4′H-3,3′-bi(1,2,4-triazole), DMF = N,N-dimethylformamide), have been solvothermally synthesized in different solvent systems. Compound 1 exhibits a (3,4)-connected net with the point symbol of (6.82)4(62.82.102), whereas 2 exhibits a rare 3D lvt-42·84 net. Moreover, an irreversible solid-state transformation from 2 to 1 was observed, and their magnetic properties were also investigated and discussed in detail. [ABSTRACT FROM AUTHOR]