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Research has been conducted on the macrocyclic oxamide's lanthanide(III)-copper(II) complexes. The synthesis and characterization of these complexes have been carried out via the use of IR, elemental analysis and electronic spectra and the details are reported.

The novel iron selenidostannates [Fe(bipy)3]Sn4Se9·2H2O (1) and [Fe(bipy)3]2[Sn3Se7]2·bipy·2H2O (2) (bipy = bipyridine) were prepared by the reactions of Sn, Se, FeCl2·4H2O, bipy, and dien with/without KSCN under hydrothermal conditions (dien = diethylenetriamine). In 1, four SnSe5 units condense via edge sharing to form the novel 3-D framework selenidostannate ∞³[Sn4Se92-] containing an interpenetrating channel system. The [Fe(bipy)3]2+ cations are accommodated in the different channels according to the conformation of the [Fe(bipy)3]2+ cation. In 2, three SnSe5 units share edges to form a 2-D ∞²[Sn3Se72-] layered anion, while two SnSe5 units and one SnSe4 unit are connected via edge sharing, forming a 1-D ∞¹[Sn3Se72-] chainlike anion. The ∞¹[Sn3Se72-], [Fe(bipy)3]2+, bipy, and H2O species are embedded between the ∞²[Sn3Se72-] layers. 2 is the first example of a selenidostannate constructed by both ∞²[Sn3Se72-]and ∞¹[Sn3Se72-] anions. The coexistence of 1-D ∞¹[Sn3Se72-] and 2-D ∞²[Sn3Se72-] anions in 2 might support the possible reaction mechanism that the ∞²[Sn3Se72-] anions are formed by condensation of the ∞¹[Sn3Se72-] chains. 1 and 2 exhibit band gaps at 1.43 and 2.01 eV, respectively [ABSTRACT FROM AUTHOR]

Solvothermal reactions of As2O3 and S with CoCl2·6H2O or NiCl2·6H2O in an aqueous solution of dien produced novel thioarsenates [Co(dien)2]-[Co(As3S3)2] (1) and [Ni(dien)2][Ni(As3S3)2] (2) (dien = diethylenetriamine), and the reaction with COCl2·6H2O in an aqueous solution of en afforded complex [Hen]2[{Co(en)}6(μ3-S)4(AsS3)4] (3) (en = ethylenediamine). In 1 and 2, one transition-metal ion is coordinated by two dien ligands to form [TM(dien)2]2+ (TM = Co, Ni) complex cations. The As3S3 unit coordinates to the other TM(II) ion with both As- and S-donor atoms to form the [TM(As3S3)2]2- anionic duster, in which TMAS², TMAs2S2, and TMAs3S2 rings are formed. In 3, each Co3+ ion is coordinated by an en ligand. Six Co(en) units are interlinked by four //3-S and four AsS3 ligands to form a [{Co(en)}6(μ3-S)4(AsS3)4]2- cluster containing an adamantane-like Co6S4 core. The AsS3 unit coordinates to Co atom in the n¹-AS11n²-S coordination mode with As binding Co(1) and S(1) binding Co(1) and Co(2). The As3S3 and AsS3 ligands with both As- and S-donor atoms in 1--3 have never been obtained in amine solution before. The same reactions in pure dien and en solvents afforded compounds [Co(dien)2]3[As3S6]2 (4) and [Co(en)3]2As2S5 (5) containing discrete anions [As3S6]3- and [As2Ss]4-, respectively. The band gaps of 1--3 are in the range of 1.37--1.55 eV, and die band gaps of 4 and 5 are 2.24 and 2.26 eV, which show the influence of the coordination mode of thioarsenate ligands on the electronic transitions in the TM-thioarsenates. [ABSTRACT FROM AUTHOR]

A sulfonate-carboxylate ligand, 4,8-disulfonyl-2,6-naphthalenedicarboxylic acid (H4-DSNDA), and eight new lanthanide coordination polymers {[Pr4(OH)4(DSNDA)2(H2O)12](H2O)10}n (1), [Ln(H2-DSNDA)0.5(DSNDA)0.5(H2O)5]n (Ln = La(2), Nd(3), Sm(4), Eu(5), Gd(6), and Dy(7)), and {[Er(H-DSNDA)(H2O)4](H2O)}n (8) have been synthesized. Detailed crystal structures of these compounds have been investigated. Compound 1 has a 3D framework featuring the unique cubane-shaped [Pr4(μ3-OH)4] clusters and is a binodal 4,8-connected network with (416∙612)(44∙62)2 topology. Compounds 2-7 are isostructural and have 2D layered structures. Compound 8 is also a 2D layer but belongs to different structural types. The luminescence behavior of compound Eu(5) shows that the π-rich aromatic organic ligands efficiently transfer the absorbed light energy to the Eu(III) ions, thus enhancing the overall luminescent properties of compound Eu(5). The magnetic properties of all compounds except for the diamagnetic La(2) compound have been investigated. In addition, elemental analysis, IR spectra, and thermogravimetric analysis of these compounds are also described. [ABSTRACT FROM AUTHOR]

Bis-pyrene derivative 1, bearing two pyrene and pyridine groups, was synthesized as a ratiometric fluorescent chemosensor for Ag+ in aqueous solution. Fluorescent chemosensor 1 displayed a selective ratiometric change with Ag+, which was attributed to the excimer-monomer emissions of pyrenes. A mechanism for the binding mode was proposed based on fluorescence changes, NMR experiments, and theoretical calculations. [ABSTRACT FROM AUTHOR]

Treatment of [Et4N][Tp*WS3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-l-yl)borate) with 2 equiv of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS2)2(μ-S2)] (2). Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH2Cl2 or CHCl3 formed three neutral W/Cu/S dusters [{Tp*W(μ3-S)3Cu3(μ-Cl)}2Cu(μ-Cl)2(μ7-Cl) (MeCN)]2 (3), [{Tp*W(μ3-S)3Cu3}2Br(μ-Br)2(μ4-Br)- (MeCN)] (4), and [{Tp*W(μ3-S)3Cu3}2{Cu2(μ-I)4(μ3-I)2}] (5), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et4NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et4N][{Tp*W(μ3-S)3Cu3X}2 (μ-X)2(μ4-X)] (6, X = Cl; 7 X = Br). Compounds 2-7 were characterized by elemental analysis, IR., UV-vis, ¹H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray crystallography. The dimeric structure of 2 can be viewed as two [Tp*WS2] fragments in which two W atoms are connected by one S22- dianion. Compounds 3-7 all possess unique halide-bridged double cubanelike frameworks. For 3, two [Tp*W(μ3-S)3Cu3]2+ dications are linked via a μ4-Cl- bridge, two μ-Cl- bridges, and a [Cu(MeCN)(μ-C1)2]+ bridge. For 4, one [Tp*W(μ3-S)3Cu3(MeCN)]2+ dication and one [Tp*W(μ3-S)3Cu3Br]+ cation are linked via a μ4-Br- and two μ-Br bridges. For 5, the two [Tp*W(μ3-S)3Cu3]2+ dications are bridged by a linear [(μ-l)2Cu- (μ3-I)2Cu(μ-I)2]4+ species. For 6 and 7, two [Tp*W(μ3-S)3Cu3X]+ cations are linked by μ4-X- and two μ-X- bridges (x = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2-7 in MeCN/CH2C12 were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique. [ABSTRACT FROM AUTHOR]

The three-dimensionally ordered macroporous (3DOM) ZrO2: Er3+, Yb3+ materials were successfully synthesized by the sol–gel method combined with a polystyrene latex sphere templating technique, and their morphologies, surface physicochemical properties, and upconversion photoluminescence (UC-PL) properties were studied. The results indicate that the materials exhibited both porosity and strong UC-PL under the excitation of a 978 nm diode laser. In comparison with the nonporous samples, the relative intensity of the red (4F9/2-4I15/2) to the green (4S3/2/2H11/2-4I15/2) emission decreased visibly because of the decreased nonradiative relaxation in the 3DOM materials. It was also observed that the relative intensity of the green emission to the red emission increased significantly with the increasing excitation power. An indirect three-photon populating process occurred for the green emission as the excitation power and Yb3+ concentration was high enough. [ABSTRACT FROM AUTHOR]