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Two pyridinium amide-based receptors L1 and L2 with a small difference of H-bond position of the amide have been synthesized and characterized. Interestingly, they exhibited a huge difference in sensing towards AcO- and H2PO4 -, respectively. Receptor L1 was found to be ‘naked-eye’ selective for AcO- anions, while receptor L2 showed clear fluorescence enhancement selective to H2PO4 - anion. The recognition ability has been established by fluorescence emission, UV-vis spectra, and 1HNMR titration.

A novel C

A novel synthesis route for the production of Sr3MgSi2O8:Eu2+,Dy3+ sub-micron quasisphere phosphor powder is reported. Both the host and activator cations were co-precipitated in water-ethanol mixed solutions and precipitation was performed with analytical grade ammonium citratetribasic. As the dispersion media, optimum concentration for PEG in the precursor solution is determined to be 0.08 g/mL. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and fluorescence spectrophotometer were employed to characterize the phosphor. The effect of the calcining temperature on the crystalline particle and luminescence properties of Sr3MgSi2O8:Eu2+,Dy3+ is systematically discussed. Sr3MgSi2O8:Eu2+,Dy3+ single phased quasi-sphere phosphor was achieved by calcining the asprecipitated precursor at 1100°C. Sr2SiO4 was identified as the intermediate phase during the calcination process. Despite the small particle size, the emission intensities were higher by the present method. However, the afterglow characteristic was not better than that prepared by solidstate reaction in the comparable condition.

The novelty of the current work lies in the simple synthesis of a new class of monodisperse, luminescent silica spheres produced upon calcination of hybrid amine-functionalized silica spheres which can known the role of ethylenediamine (en) on the morphology and luminescence properties of the resultant silica spheres.

Infiltration of a nano-sized alumina sol into the green bodies is proposed to facilitate the ceramic sintering. The green samples were prepared by a colloidal processing based on drying induced forming, and then were immersed in a nano-sized alumina sol prior to their sintering at 1350-1600 oC. The alumina sol was characterized by using transmission electron microscopy and the grain structure of sintered alumina ceramics were examined by scanning electron microscopy. Significant densification of sintered samples was evidenced, in a depth of ~ 0.5 mm, on the samples treated with the alumina sol infiltration. It is indicated that filling of nano-sol into the micro-pores between particles of green samples enhanced the sintering densification process. The infiltration treatment by nano-sol may also provide an effective way to produce structurally gradient ceramics with a gradual changing density and/or composition from the surface into bulk.

A novel method for synthesizing long afterglow silicate phosphor Sr3MgSi2O8:Eu2+,Dy3+using TEOS and inorganic powders as reactants was reported. Acetic acid as a catalyzer controlled the hydrolysis of TEOS by adjusting pH value of the system. The morphologies of precursor were characterized by transmission electron microscope (TEM). The structure and optical properties of the phosphor powders were systematically investigated by means of X-ray diffraction and spectrofluorometry. TEM images have reflected the core-shell structure and quasi-spherical morphology of the precursor particles. It was found that the single-phase Sr3MgSi2O8 crystalline structures were obtained at 1050 and 1250 °C for the samples prepared with the nano-coating method and the solid state reaction, respectively. The emission intensities of the phosphors prepared by the present method were higher than those by the conventional process. Also, the afterglow characteristic was better than that prepared by solid-state reaction in the comparable condition.

Reaction of the oligo(phenylenevinylene) 4,4′-bis(2,5-dimethylstyryl)biphenyl (bdb) with CF3CO2Ag in benzene gave a novel octanuclear sandwich cluster [Ag8(bdb)2(C6H6)2(CF3CO2)8]·2C6H6 (1). The clusters are packed on each other through strong π-π interactions to form 1D ′brick′ chains, between which the solvated benzene molecules are located. TG analysis showed that cluster 1 could completely liberate the guest benzene molecules at 105 °C and the coordinated benzene molecules at 180 °C. In solid state, cluster 1 exhibits fluorescence, and the emission band is red-shifted compared with that of free ligand bdb.

The 2D porous copper(I) complex with 1,3-dicyanobenzene (DCB), [Cu(DCB)2](PF6)(Me2CO) 1, exhibits channels along axis c, in which one molecule acetone and one anion PF−6 per formula unit are included respectively. The reversible incorporation of guest acetone and acetonitrile, as well as the anion exchange from PF−6 to BF−4 or CF3SO−3, was investigated by thermogravimetric (TG) analysis, 1H NMR spectra and/or infrared absorption spectroscopy. Additionally, the incorporation of benzene and toluene into complex 1 was also discussed. Complex 1 exhibited size selectivity for guest inclusion or anion exchange.

Nanocomposite sol comprised of hydroxyapatite (HA) and silk fibroin (SF) was synthesized via a wet-mechanochemical route. SF particles were chemically modified using an alkali solution attempting to disentangle their surface fibrils so as to enhance the effective contact between the mineral and the organic particles. With the alkali pretreated SF involved, Vickers microhardness of the composite increases by 57% and a more enhanced three-dimensional porous network with a homogenous particle form and a uniform pore size distribution is formed through the intimate crosslinkage between HA clusters and SF fibrils. In addition, the alkali pretreatment of SF not only increased the viscosity and the rigidity of the composite sol, but also promotes its gelation process, which is favorable for healing bone defects by an injection technique.

Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag2(bmsb)(ClO4)2] (1), [Ag2(bmsb)(H2O)4](BF4)2 (2), and [Ag2(bdb)(CF3SO3)2] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands.

Four copper(I) complexes of 2,11-dithia[3.3]paracyclophane (dtpcp), [CuI(dtpcp)] · MeCN (1), [CuBr(dtpcp)] · MeCN (2), [CuCl(dtpcp)] · MeCN (3) and [Cu2I2(dtpcp)2] · Me-thf (4) (Me-thf=2-methyltetrahydrofuran), have been synthesized and their molecular structures determined by X-ray crystallography. Complexes 1 and 2 are isostructural, and exhibit 3D networks with elliptical channels along a-axis, which are constructed by dtpcp molecules bridging zigzag CuI and CuBr chains, respectively. Complexes 3 and 4 are 2D porous sheet networks constructed by bridging the zigzag copper-dtpcp chains via rhombic ring of Cu2X2 (X=Cl or I). All sheets in 3 are packed in an eclipsed manner through π–π stackings to generate channels along the a-axis. However, the 2D porous sheets in 4 are packed in an offset mode such that channels are not formed along c-axis. Complexes 1 and 2 can reversibly incorporate guest acetonitriles without collapse of structures, and the original frameworks of 1 and 2 are completely recovered after incorporation of guests which are confirmed by X-ray powder diffraction (XRPD) pattern and 1H NMR spectrum. Additionally, complex 1 exhibits selectivity in size and polarity for guest inclusion.

A new type of silver(I) coordination complex derived from silver(I) perchlorate (or triflate) and polycyclic aromatic compounds is reviewed. Structural studies by single-crystal X-ray diffraction have shown that all compounds contain extended one- to three-dimensional structures in which several metal atoms are sandwiched between two fused polycyclic systems. Special attention is paid to the combination of the plasticity of the metal ion, coordinative versatility of the aromatic ligand, solvent effect and the nature of the counteranions for designing metal complexes with a wide range of infinite frameworks.

This paper describes three novel and distinctive organosilver(I) complexes with propeller ligand, hexaphenylbenzene (HPB), whose structures are controlled by selected solvents and anions. Treatment of HPB with AgClO4 and AgCF3SO3 in toluene gave, complexes [Ag4(HPB)(ClO4)4] 1 and [Ag2(HPB)(CF3SO3)2(toluene)] 2, respectively. The single-crystal X-ray analysis revealed that 1 contains 2-D sheet framework whereas 2 consists of 1-D chain structure. In both complexes the anions play the role of linkers instead of spacers in the construction of polymeric structures. In contrast, complex [Ag2(HPB)(ClO4)2(THF)2] 3, obtained by using tetrahydrofuran (THF) in place of toluene in the synthetic process of 1, exhibits a discrete dimer. The fundamentals of the synthesis of these complexes, influences of anions and solvents on their coordination networks, and physicochemical properties are discussed. The present findings may serve as a basis for understanding the construction of solid-state materials with designed archi...

A new class of metal sandwich complexes of silver derived from silver(I) perchlorate and fluoranthene (L1), benzo[ghi]perylene (L2), [2,2]paracyclophane (L3), and decacyclene (L4) was prepared. The idea behind the use of polycyclic aromatic compounds as an alternative approach for construction of organometallic sandwich systems is to combine the plasticity of the metal ion and planarity and coordinative diversity of the hydrocarbons. Structural studies by single-crystal X-ray diffraction have shown that all compounds contain extended one- to three-dimensional structures in which several metal atoms are sandwiched between two fused polycyclic systems. While complex 1, [Ag3(L1)2(ClO4)3], exists in the solid state as a two-dimensional W-type architecture in which AgClO4 layers are separated by two sheets of hydrocarbon, complex 2, [Ag(L2)(ClO4)]4·toluene, contains two double-decker polymeric chains coupled via extensive aromatic π−π stackings. Pillared brick sandwiched framework was observed in 3, [Ag(L3)(Cl...

This paper describes two copper(I) supramolecules with the same anion and cation but quite different topologies and properties. The reaction of [Cu(CH(3)CN)(4)]PF(6) and 1,2,4,5-tetracyanobenzene (TCNB) leads to two novel polymeric coordination compounds, [Cu(2)(TCNB)(3)](PF(6))(2)(Me(2)CO)(4)( )()(1) and [Cu(2)(TCNB)(3)](PF(6))(2) (2), depending on the solvents used. The crystal structures have been determined by single-crystal X-ray diffraction. Crystal data are as follows. 1: C(21)H(15)N(6)O(2)CuPF(6), monoclinic, P2(1)/a, a = 11.553(4) Å, b = 16.135(7) Å, c = 15.046(3) Å, beta = 108.08(2) degrees, Z = 4. 2: C(15)H(3)N(6)CuPF(6), orthorhombic, Cmcm, a = 28.282(3) Å, b = 10.337(3) Å, c = 16.285(4) Å, Z = 16. In both polymers, copper(I) ions have similar pseudotetrahedral environments and the four coordination sites are fully occupied by the four bridging ligands, twomgr;(2)-TCNB and twomgr;(4)-TCNB groups. Polymer 1, obtained in acetone, revealed a two-dimensional zigzag sheet network between copper(I) ions, whereas 2, synthesized in methylethyl ketone, displayed a three-dimensional porous framework with different functional groups (or atom) in different cavities. The redox, magnetic, and conductive behaviors of both complexes are discussed. It is demonstrated that the two complexes give different physicochemical properties.

Four organosilver(I) complexes of polycyclic aromatic hydrocarbons (PAHs) have been investigated crystallographically. The aim was to establish whether a favorable combination of cation-π interactions and aromatic stackings might produce functional organometallic solid materials with novel networks. Complete structures of the silver(I) perchlorate with 9,10-diphenylanthracene (L1), rubrene (L2), benzo[a]pyrene (L3), and coronene (L4) were determined by X-ray diffraction. All compounds are organometallic species based on cation-π interactions. While complex 1 with L1 revealed a discrete mononuclear structure, complex 2 with rubrene displayed a π-bonded 3-D polymer. Complexes 3 and 4 can be regarded as both coordination polymer and stacking polymer, and the detailed differences in the geometries and the stacking patterns of L3 and L4 gave helical and triple-decker networks, respectively. The ESR spectroscopic results and conductivity of the compounds are also discussed. The present findings may serve as a b...

The title compound, {[Ag2(C16H16S2)2(C2H3N)4](C8F4O4)·2C8H2F4O4·4C2H3N}n, has been prepared from the reaction of 2,11-di­thia­[3.3]­paracyclo­phane (dtpcp) and in situ silver(I) tetrafluoroterephthalate (TFTP2−) using an interface method. In the solid state the title compound forms two infinite chains, which are parallel to one another. One chain consists of [Ag2(C16H16S2)2(C2H3N)4]n2n+, and the other is formed from TFTP2− and H2TFTP via Oc—H⋯Oc (c is carboxy) hydrogen- bonding interactions, with H⋯A distances of 1.72 (2) and 1.774 (19) A. The AgI ion is tetrahedrally coordinated by two aceto­nitrile N atoms and two dtpcp S atoms. The cyclo­phanes have inversion symmetry.

The title compound, {[Ag(C16H16S2)(C2H3N)2](C6HF8O4)}n, forms two infinite chains, which are approximately perpendicular to each other. One chain consists of [Ag(C16H16S2)(C2H3N)2]nn+, and the other is formed from HOFA− (HOFA− is hydrogen octa­fluoro­adipate) units via Oc—H⋯Oc (c is carboxy) hydrogen-bonding interactions, with an H⋯A distance of 1.66 (5) A. Each silver(I) cation lies on a crystallographic twofold rotation axis and has a tetrahedral geometry, defined by two N atoms belonging to two aceto­nitrile mol­ecules and two S atoms from two 2,11-di­thia­[3.3]­para­cyclo­phane mol­ecules. The cyclophanes have inversion symmetry.

A homogeneous and stoichiometric Sr3MgSi2O8: Eu2+ (SMSE) phosphor has been prepared by a simple sol-gel Approach. TEM, SEM, XRD and spectrofluorimeter were used to monitor the structure evolution and optical properties of the phosphor. While TEM/SEM image of as-calcinated phosphor disclosed a spherical morphology with average size of 0.5 μm. X-ray diffraction (XRD) of the SMSE powder displayed a pure Sr3MgSi2O8 pattern after annealing at 1100°C for 2 h. The luminescence intensity of the sol-gel-derived phosphors is much higher in comparison with that of the solid-state-derived phosphors.

A silver(I) compound with the propeller ligand hexaphenylbenzene has been synthesized, which shows the high degree of silver ions ordering around the peripheral rings of each propeller, forming a 2-D sheet framework.