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Two new heterometallic uranyl-organic frameworks (UOFs), [Cd(phen)2(H2O)2][(UO2)2(BDC)3]·2H2O (1) and [Ni(phen)3][(UO2)2(BDC)3]·2H2O (2), were obtained under hydrothermal conditions. Both crystal structures were characterized by single-crystal X-ray diffraction analyses and the results indicate that both complexes feature a similar 2D honeycomb framework that is connected by rigid benzenedicarboxylate (BDC) ligands and uranyl units. BDC works as a linker to bridge neighboring UO22+ units, where UO22+ is tris-chelated. Different guest molecules guided the stacking of 2D layers and lead into their 3D supramolecular crystal structures with different space groups. As a result, 1 crystallized in a polar space group Cc, whereas 2 belongs to a chiral space group P6122. Thermogravimetric measurements were performed to study their thermal stability. UV-visible diffuse reflectance spectroscopy measurements indicate an experimental optical bandgap of 3.87 eV and 3.63 eV, respectively, for 1 and 2. Luminescent studies of both samples show strong green light emissions. [ABSTRACT FROM AUTHOR]

Two new organic/bismuth(III) iodide hybrids have been synthesized by a solution process, and their crystal structures were determined by an x-ray diffraction method. The first one, (EMP)3(Bi2I9) (EMP+ = N-ethyl-4-methyl-pyridinium) (1), crystallizes in the monoclinic system, space group P21/c, with M r = 3838.20, a = 19.945(4), b = 12.636(3), c = 20.327(4) Å, β = 118.82(3)°, V = 4488.4(16) Å3, Z = 2, D c = 2.840 g/cm3, F(000) = 3358, μ(MoKα) = 14.039 mm−1, the final R = 0.0678, and wR = 0.1676 for 7272 observed reflections with I > 2σ(I). The second, [(Phendione)BiI4]·(Phendione-H)·C2H5OH (Phendione = 1,10-phenathroline-5,6-dione) (2), belongs to the monoclinic system, space group C2/c, with M r = 1183.02, a = 37.254(8), b = 8.1776(16), c = 22.318(5) Å, β = 111.38(3)°, V = 6331(2) Å3, Z = 8, D c = 2.842 g/cm3, F(000) = 4296, μ(MoKα) = 9.511 mm−1, the final R = 0.0526, and wR = 0.1050 for 6555 observed reflections with I > 2σ(I). Compound 1 contains halobismuthate dimers, and it is noteworthy that the dimers and its organic countercations connect with each other by C–H···I hydrogen bonds to form a layered structure. Compound 2 is composed of [(Phendione)BiI4]− anions and Phendione-H+ cations, and hydrogen bonds contribute to give a one-dimensional (1-D) chain. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.17 and 1.93 eV, respectively. [ABSTRACT FROM PUBLISHER]

A new Lewis-base adduct of the iodo-bridged lead(II) compound {[PbI2(DPP)]·DMF} n (1) (DPP = 4,7-diphenyl-1,10-phentheanthroline) has been synthesized and structurally determined. The compound 1 crystallizes in the monoclinic system, space group P21/a, with unit cell parameters a = 9.1129(3), b = 24.0033(5), c = 24.4016(6) Å, β = 95.9460(9)°, V = 5308.9(2) Å3, Z = 8, M r = 866.48, D c = 2.168g/cm3, F(000) = 3216, μ(MoKα) = 8.706, and the final R = 0.0373 and wR = 0.0902 for 9408 observed reflections with I ≥ 2σ(I). In 1, the lead centers are in a distorted octahedral environment with stereochemical active 6s2 lone pair, and a one-dimensional chain via edge-sharing of PbI4N2 octahedra can be observed. Furthermore, π···π interaction and hydrogen bonds contribute to the formation of a three-dimensional (3-D) network. The optical band gap of 1 is 2.66 eV, judged from the absorption spectrum. Its fluorescence has also been discussed. Density function theory (DFT) calculation was executed for its electronic structure. [ABSTRACT FROM AUTHOR]

A new cation-induced hybrid iodoargentate, [(PIP-H2)4·(Ag4I12)·H2O]n (1) (PIP = piperazine) has been obtained by the routine synthetic reaction in DMF solution and structurally determined. 1 crystallizes in monoclinic system, space group P21/n with unit cell parameters: a = 12.718(3), b = 9.3861(19), c = 20.098(4)Å, β = 90.33(3)°, V = 2399.1(8)Å3, Z = 4, C8H24Ag2I6N4O, Mr = 1169.45, Dc = 3.238 g/cm3, F(000) = 2080, μ(MoKα) = 9.356mm-1, the final R1 = 0.0681 and wR = 0.1757 for 5255 observed reflections with I > 2σ(I). In 1, 0-D [Ag4I12]8- clusters were constructed from four vertex-sharing AgI4 tetrahedra and further linked by hydrogen bonds to give a 2-D layer. Luminescence can be detected in the title compound. Quantum chemistry calculation with DFT method was carried out to reveal its electronic structure. [ABSTRACT FROM AUTHOR]