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A benzothiazolium-derived colorimetric and fluorescent chemosensor (L) for mercury ions has been prepared. The detection limits of the colorimetric and fluorescent method are 15.3 and 11.8 ppb, respectively, much lower than the reported chemosensors based on similar derivatives of benzothiazolium. The optimized molecular structures, absorption and fluorescence characteristics of the chemosensor and its complex with mercury ions were performed using calculations at the B3LYP/LanL2DZ level of theory, in combination with Atoms in Molecules and Natural Bond Orbitals analyses.

A new dansyl–diethylenetriamine–thiourea conjugate (DT) was prepared as a highly selective and sensitive fluorescent chemodosimeter for Hg2+ ions. A Hg2+-induced desulfurization reaction followed b...

We synthesized new mesostructured materials through the surfactant-templated assembly of octahedral rhenium cluster [Re6Q8(CN)6]4– (Q = Te, Se and S) anions. The mesostructured lamellar phases with the general formula [CnH2n+1N(CH3)3]4[Re6Q8(CN)6] (n = 14, 16, 18; Q = Te, Se, S; 1: n = 14, Q = Te; 2: n = 16, Q = Te; 3: n = 18, Q = Te; 4: n = 16, Q = Se; 5: n = 16, Q = S) were prepared by an ion exchange/precipitation reaction of alkyltrimethylammonium surfactants and the corresponding cluster K4[Re6Q8(CN)6] in an H2O/acetone medium at room temperature. The orange plate-like crystals of 1 and 4 were obtained by slow concentration of their solutions and their crystal structures determined by single-crystal X-ray diffraction. In the structure, the rhenium clusters form layers with a pseudo-hexagonal arrangement, and these inorganic layers are separated by a bilayer of interdigitated surfactant cations. Compounds 1–5 were characterized using powder X-ray diffraction, TEM, IR, Raman, FL, UV/Vis spectroscopy, and thermogravimetric analysis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

A new nonoxidic mesostructured material with highly ordered hexagonal symmetry, [C(16)H(33)N(CH(3))(3)](3)Mn(0.5)[Re(6)Te(8)(CN)(6)], has been obtained through supramolecular assembly of [Re(6)Te(8)(CN)(6)](4-) clusters in the presence of a transition metal cation, Mn(2+), with cetyltrimethylammonium bromide as a liquid crystal template under hydrothermal conditions.

We study the intermediate phases and their evolution during crystallization of Aluminophosphate molecular sieves. In this work, the behaviors of the initial gel and the evolution of the intermediate phases during crystallization of AlPO4-5 molecular sieve using triethylamine as a template have been investigated. It has been shown that in the amorphous aluminophosphate gel phases, template triethylamine does exist in protonated form; and there appear a significant change, formation of 12-member rings of AlPO4-5 structure, during the early stage of crystallization of AlPO4-5. In addition, a proposition to explain the crystallization of AlPO4-5 is also suggested.