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In this work, a versatile multi-dentate 1,2-bis(pyridin-4-ylmethylene)hydrazine (L) ligand has been employed to construct three novel iron(II) coordination complexes, [Fe(L) 2 (NCS) 2 (H 2 O) 2 ]·2H 2 O ( 1 ), [Fe(L)(NCS) 2 (H 2 O) 2 ] ( 2 ) and {[Fe(L) 2 (NCS) 2 ]·2CH 3 OH} n ( 3 ) (NH 4 NCS = ammonium thiocyanate), which can be isolated under similar synthetic conditions, only different molar ratio of metal/ligand or different solvent systems are used. 1 is a mono-nuclear iron(II) coordination complex, and 2 is a one-dimensional (1D) iron(II) coordination complex, while 3 is a 2D micro-porous iron(II) framework with the channel dimensionality of 13.936(3) Å × 13.936(3) Å. PXRD patterns also confirm the purity of the bulky samples of 1 – 3 . For 1 – 3 , it represents the first example of solvent-induced drastic reversible dynamic conformation between different dimensional iron(II) coordination complexes 1 (0D), 2 (1D) and 3 (2D) (for 1 : water; for 2 : benzene; for 3 : methanol/acetone/acetonitrile), which are unambiguously confirmed by PXRD characterizations. Variable-temperature magnetic susceptibility data of 2 – 3 have been recorded in the 2–300 K temperature range, indicating weak antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

A novel three-dimensional europium metal-organic framework (Eu-MOF), [Eu(L)(OAc)(DMA)] n ( 1 ), has been successfully obtained based on a newly designed ligand 4′-(3,5-dicarboxyphenyl)-4,2′:6′,4″-terpyridine (H 2 L). The structure of 1 was established by single crystal X-ray diffraction technique, and structure analysis shows that two Eu 3 + in 1 are 4-fold bridged by two η 1 :η 1 :μ 2 carboxylates from L 2 − and the other two η 1 :η 2 :μ 2 carboxylates from acetic acid, respectively. The binuclear [Eu 2 ] were further linked by L 2 − to form a 3D framework. The investigations on luminescent properties reveal that 1 can detect Al 3 + quickly with relatively high sensitivity and selectivity. More importantly, it displays high thermal and solvent stability. Additionally, a self-made fluorescence test paper fabricated based on 1 was used to detect Al 3 + in practice. [ABSTRACT FROM AUTHOR]

Abstract: Three new nickel(II) complexes [Ni2(btec)(azopy)2(H2O)8]·2H2O (1), {[Ni(H2btec)(azopy)(H2O)2]·(azopy)} n (2) and {[Ni4(btec)2(azopy)3(H2O)10]·8H2O} n (3) (H4btec=1,2,4,5-benzenetetracarboxylic acid; azopy=4,4′-azobispyridine) have been synthesized by tuning the reaction temperature and the metal–ligand ratio. They were characterized by single-crystal X-ray diffraction and elemental analysis. 1 shows a binuclear structure, 2 exhibits a 2D grid, and 3 features an interesting 3D framework with (63)(4.62)(42.62.82) topology formed by two types of interlocked 2D layers. [Copyright &y& Elsevier]

Abstract: Under hydrothermal conditions using cis-butenedioic acid (H2L) and corresponding lead(II) salts, a three-dimensional (3D) lead(II) complex {[Pb2(L)(μ2-Cl)(μ3-Cl)]} n (1) containing 3D Pb–X–Pb (X=O and Cl) linkage has been isolated. 1 also represents a truly 3D hybrid luminescent lead(II) framework with I 3 O 0 type connectivity. Further analysis reveals that cis- and trans-conformations of butenedioic acid ligand greatly affect the lead(II) framework structure. Solid-state fluorescence spectrum of 1 exhibits the maximum emission peak at 379nm. [Copyright &y& Elsevier]

Abstract: Two copper(II)–poly(pyrazolyl)methane complexes [Cu2(bpm)4(ta)](ClO4) 2 ·2H2O 1 and {[Cu2(tpm)2(ta)2]·H2O} n 2 (bpm=bis(3,5-dimethylpyrazolyl)methane, tpm=tris(pyrazolyl)methane, H2ta=terephthalic acid) were synthesized and characterized by elemental analysis, FT-IR and UV–vis spectra. 1 is a binuclear complex, while 2 exhibits as a 1D zigzag coordination polymer. [Copyright &y& Elsevier]

Utilizing 1,3,4-oxadiazole amide that possesses outstanding electron mobility to serve as auxiliary ligands, four novel iridium (III) complexes of Ir1 – Ir4 were prepared. Their structure, photophysical, and electrochemical characteristics were examined in detail, and quantum chemical calculations were used to interpret their photophysical behaviors. At room temperature, complexes Ir1 and Ir2 exhibit almost coincident green phosphorescence with peaks at 506 nm. Ir3 and Ir4 complexes produce greenish blue and greenish yellow light with a double-peak structure located at 496 and 531 nm. Organic light-emitting diodes utilizing Ir1 – Ir4 as emitters exert extremely moderate efficiency roll-off, which is caused by the emitters bearing CF 3 -substituted 1,3,4-oxadiazole amide possessing excellent electron mobility. [Display omitted] • Iridium complexes Ir1–Ir4 with CF 3 -substituted 1,3,4-oxadiazole amide ancillary ligands are synthesized. • Both Ir1 and Ir2 exhibit green phosphorescence, Ir3 and Ir4 produce greenish blue and greenish yellow light, respectively. • Complexes Ir1–Ir4 have excellent thermal and electrochemical stability. • The OLEDs based on Ir1–Ir4 exhibit very mild efficiency roll-off. [ABSTRACT FROM AUTHOR]

One new three-dimensional Cd(II) polymer [Cd 3 (MMA) 2 (INA) 2 ] n ( 1 ) was synthesized hydrothermally based on mixed flexible methylmalonic acid (H 2 MMA) and rigid isonicotinic acid (HINA) ligands. Single-crystal X-ray diffraction analysis reveals that compound 1 has a 3D framework structure consisting of 2D {Cd 3 } layer unit and INA − connector, which bears a (3,8)-connected tfz-d topology with Schläfli symbol of {4 3 } 2 {4 6 .6 18 .8 4 }. The solid-state luminescent property was studied and 1 exhibits strong emission centered at 429 nm. [ABSTRACT FROM AUTHOR]

A cationic iridium complex [Ir(dfpmpy) 2 (pzpy)](PF 6 ) with 2-(1H-pyrazol-1-yl)pyridine as ancillary ligand has been prepared, and its crystal structure, photophysical and electrochemical properties have been investigated. In degassed CH 3 CN solution, this complex exhibits blue emission with a peak wavelength of 451 nm. Photophysical property indicates that photoluminescence of complex [Ir(dfpmpy) 2 (pzpy)](PF 6 ) originates mainly from ligand-centered 3 π → π ∗ states. In addition, solution-processed organic light-emitting diodes based on [Ir(dfpmpy) 2 (pzpy)](PF 6 ) have been fabricated. A blue light electroluminescence (484 nm) was observed and a maximum current efficiency of 1.56 cd A −1 corresponding to a maximum power efficiency of 0.33 lm W −1 , has been achieved. This demonstrates that this complex is a promising phosphor for achieving efficient electrophosphorescence in the blue light region. [ABSTRACT FROM AUTHOR]

Two new cationic iridium complexes bearing cyclometalated carbene ligands have been prepared, and the photophysical and electrochemical properties have been investigated. In degassed acetonitrile solutions, these complexes exhibit yellow light emission with peaks at 591 and 579 nm, respectively. Both photophysical properties and quantum chemical calculations indicate that photoluminescence of these complexes are mainly from triplet charge-transfer excited states. Solution-processed organic light-emitting diodes based on these complexes exhibit yellow electroluminescences with the maximum current efficiencies of 17.42 and 6.36 cd A −1 and Commission Internationale d’Énclairage(x, y) coordinates (CIE x,y ) of (0.47, 0.51) and (0.51, 0.47), respectively. [ABSTRACT FROM AUTHOR]

In this work, we report three deep-blue emitting cationic iridium complexes Ir1–Ir3 with 2ʹ,6ʹ-difluoro-2,3ʹ-bipyridine cyclometalated ligand and pyrazole-type ancillary ligands. Synthesis, crystal structure, photophysical and electrochemical properties of Ir1–Ir3 are studied in detail. Ir1–Ir3 exhibit efficient phosphorescence emissions at 439, 438 and 437 nm with CIE 1931 coordinates of (0.14, 0.12), (0.14, 0.12) and (0.14, 0.13), and luminescence quantum yields of 0.35, 0.27 and 0.50 in CH 2 Cl 2 solutions, respectively, which are among the highest levels of ever reported cationic iridium(III) complexes emitting deep-blue light. High luminescence quantum yields, excellent color purity and short lifetimes demonstrates the great potential of Ir1–Ir3 for light-emitting electrochemical cells (LECs) and solution-processable organic light-emitting diodes (OLEDs) as efficient blue emitters. Image 1 • Deep-blue emitting cationic iridium complexes. • Ir1−Ir3 are synthesized. • Ir1−Ir3 exhibit high photoluminescence quantum yields in CH 2 Cl 2 solutions. [ABSTRACT FROM AUTHOR]