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A series of blue phosphorescent heteroleptic cyclometalated Ir (III) complexes with mesitylphenyl‐imidazole ligands for organic light‐emitting devices are investigated theoretically to explore their electronic structures, spectroscopic properties, and application value for organic light‐emitting devices. FCNIr, (FCN)2Ir(tpip), (FCN)2Ir(acac), (CN)2Ir(tpip), (CN)2Ir(acac), and CNIr are investigated with density functional theory approaches, where, for (FCN)2Ir(acac), FCN denotes 2,4‐difluorobiphenyl3‐carbonitrile and acac denotes acetylacetonate; for (FCN)2Ir(tpip), tpip denotes tetraphenylimido‐diphosphonate); and for (CN)2Ir(acac) and (CN)2Ir(tpip), CN denotes biphenyl‐3‐carbonitrile. [ABSTRACT FROM AUTHOR]

The title compound, [Cd3(C8H10O4)3(C12H9N3)2(H2O)2] n or [Cd3(chdc)3(4-PyBIm)2(H2O)2] n, was synthesized hydrothermally from the reaction of Cd(CH3COO)2·2H2O with 2-(pyridin-4-yl)-1 H-benzimidazole (4-PyBIm) and cyclohexane-1,4-dicarboxylic acid (1,4-chdcH2). The asymmetric unit consists of one and a half CdII cations, one 4-PyBIm ligand, one and a half 1,4-chdc2− ligands and one coordinated water molecule. The central CdII cation, located on an inversion centre, is coordinated by six carboxylate O atoms from six 1,4-chdc2− ligands to complete an elongated octahedral coordination geometry. The two terminal rotationally symmetric CdII cations each exhibits a distorted pentagonal-bipyramidal geometry, coordinated by one N atom from 4-PyBIm, five O atoms from three 1,4-chdc2− ligands and one O atom from an aqua ligand. The 1,4-chdc2− ligands possess two conformations, i.e. e, e- trans-chdc2− and e, a- cis-chdc2−. The cis-1,4-chdc2− ligands bridge the CdII cations to form a trinuclear {Cd3}-based chain along the b axis, while the trans-1,4-chdc2− ligands further link adjacent one-dimensional chains to construct an interesting two-dimensional network. [ABSTRACT FROM AUTHOR]

The three novel, discrete palladium(II)-oxo clusters [CaPd12O8(PhAsO3)8]6− ( CaPd12), [SrPd12O6(OH)3(PhAsO3)6(OAc)3]4− ( SrPd12), and [BaPd15O10(PhAsO3)10]8− ( BaPd15) encapsulating alkaline earth metal ions were prepared and fully characterized by a multitude of solution and solid-state physicochemical techniques. We have discovered a structure-directing template effect induced by the respective size of the alkaline earth guest ion, which determines the detailed condensation arrangement of the peripheral PdII-oxo shell. The unprecedented SrPd12 with an open-shell type structure is of particular importance and reflects a successful strategy for deliberate design of new structural classes of polyoxo-noble-metalates. Furthermore, the unusual acetate-water ligand exchange phenomenon renders SrPd12 as a promising candidate for noble-metal-based catalysis. [ABSTRACT FROM AUTHOR]

A series of heteroleptic cyclometalated Ir(III) complexes for organic (OLEDs) application have been investigated theoretically to explore their electronic structures and spectroscopic properties. The geometries, the electronic structures, the lowest-lying singlet absorptions and triplet emissions of Ir(dfppy)2(tpip), Ir(tfmppy)2(tpip), and theoretically designed models of Ir(ppy)2(tpip) were investigated with the density functional theory (DFT)-based approaches, where ppy = 2-phenylpyridine, dfppy = 4,6-difluorophenylpyridine, tfmppy = 4-trifluoromethylphenylpyridine, and tpip = tetraphenylimidodiphosphinate. Their structures in the ground and their excited states have been optimized at the DFT/Becke 3-parameter Lee Yang Parr (B3LYP)/Los Alamos National Laboratory 2-double-z (LANL2DZ) and time-dependent DFT/B3LYP/LANL2DZ levels, and the lowest absorptions and emissions were evaluated at B3LYP and M062X level of theory, respectively. Furthermore, the energy transfer mechanism together with the advantage of low efficiency roll-off for these complexes also can be analyzed here. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The series of heteroleptic cyclometalated Ir(III) complexes for organic light-emitting display application have been investigated theoretically to explore their electronic structures and spectroscopic properties. The geometries, electronic structures, and the lowest-lying singlet absorptions and triplet emissions of Ir-(pmb)3 and theoretically designed models Ir-(Rpmb)2pic were investigated with density functional theory (DFT)-based approaches, where pmb = phenyl-methyl-benzimidazolyl, pic = picolinate, and R = H/F. Their structures in the ground and excited states have been optimized at the DFT/B3LYP/LANL2DZ and TDDFT/B3LYP/LANL2DZ levels, and the lowest absorptions and emissions were evaluated at B3LYP and M062X level of theory, respectively. The mobility of holes and electrons were studied computationally based on the Marcus theory. Calculations of ionization potentials were used to evaluate the injection abilities of holes into these complexes. The reasons for the higher electroluminescence efficiency and phosphorescence quantum yields in Ir-(Rpmb)2pic than in Ir-(pmb)3 have been investigated. The designed moleculars are expected to be highly emissive in pure-blue region. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article focuses on the growing interest in the synthesis and design of metal-organic coordination polymers. It discusses the intriguing molecular topologies and the structural diversity of metal-organic coordination polymers as well as their potential as a new class of solid-state materials. It also highlights the important role played by the judicious selection of bridging ligands in the construction of such materials.

Hydro­thermal reaction of Zn(NO3)2·6H2O with pyridine-2,5-dicarboxylic acid, 4,4′-bipyridine and pyridine in a 1:1:1:2 molar ratio affords the title complex, (C10H10N2)[Zn(C7H3NO4)2(H2O)2], in which both ions are centrosymmetric. The ZnII atom is octahedrally coordin­ated by two pyridine-2,5-dicarboxyl­ate chelating ligands and two water mol­ecules in a distorted octa­hedral geometry. 4,4′-Bipyridinium, acting as counter-ion, has hydrogen-bonding inter­actions with pyridine-2,5-dicarboxyl­ate, forming a three-dimensional structure. [ABSTRACT FROM AUTHOR]

The reaction of 3,5-diamino­benzoic acid, 1,10-phenanthroline, NaN3 and ZnII in basic aqueous solution gave rise to the title compound, [Zn(C7H7N2O2)(N3)(C12H8N2)(H2O)2]·H2O. The ZnII atom is six-coordinate with a distorted octa­hedral geometry. The two aqua ligands are in cis positions and the 3,5-diamino­benzoate ligand binds to the central Zn atom through one of its amino groups. [ABSTRACT FROM AUTHOR]

The VV ion in the title complex, [V(C15H12N2O4)(C3H7O)O], is in a distorted square-pyramidal environment. Two O atoms and one N atom from the tridentate hydrazidate ligand, and an O atom from the depronated solvent mol­ecule, define the basal plane, and the oxo O atom occupies the apical position. [ABSTRACT FROM AUTHOR]