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The reaction of the decadentate ligand tpmen (H4tpmen = N,N,N'N'-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine) with MnCl2·4H2O in aqueous solution gives a homodinuclear complex [Mn2(H2O)2(tpmen)]·16H2O, which has been characterized by elemental analysis, thermal gravimetric and single-crystal X-ray diffraction analysis. The complex crystallizes in the orthorhombic system, space group Cmca, a = 28.786(5) Å, b = 11.5033(19) Å, c = 14.437(2) Å, Z = 8, R1 = 0.0432, wR2 = 0.0786. The tpmen ligand contains four picolinate groups, two of which bind each Mn(II) to form a dinuclear complex. The geometry around the Mn(II) is distorted octahedral with two nitrogen and two oxygen atoms from the picolinate groups and two oxygen atoms from coordinated water. The variable-temperature (2-300 K) magnetic susceptibilities shows an antiferromagnetic interaction between Mn(II) ions. [ABSTRACT FROM AUTHOR]

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]

[Display omitted] • Complexes 1a , 1b , 2a , 2b , 3a and 3b contain a stable four-membered chelating ring. • The modulation of the luminescence color from green to blue-green and red was achieved. • The OLEDs based on 1a , 1b , 2a , 2b , 3a and 3b exhibit low efficiency roll-off. Six dpppy (P,P-diphenyl-N-(pyridin-2-yl)phosphinic amide)- and dppq (P,P-diphenyl-N-(quinolin-2-yl)phosphinic amide)-based iridium(III) complexes 1a , 1b , 2a , 2b , 3a and 3b containing four-membered chelate architecture were synthetized. Their crystal structure and photophysical properties were investigated. The crystal structure shows that two coordinating N atoms from the ancillary ligand dpppy and dppq form a four-membered chelate architecture with the centered iridium(III). By changing the substituent groups and conjugation of the cyclometalated ligand, the control of the luminescent color of the complexes was achieved. In CH 2 Cl 2 solution, complexes 1a , 1b , 2a , 2b , 3a and 3b emitted phosphorescence peaked at 509, 506, 479, 478, 620 and 618 nm with CIE color coordinates of (0.29, 0.60), (0.27, 0.61), (0.13, 0.37), (0.14, 0.35), (0.67, 0.33) and (0.67, 0.33), respectively. The quantum chemical calculation shows that their emitting light is primarily from 3LC π−π* states of the cyclometalated ligand. Electroluminescent devices with dual light-emitting layers were fabricated and exhibited mild efficiency roll-off. [ABSTRACT FROM AUTHOR]

Abstract: Three complexes with different structures were obtained by reacting 2,3,5-pyridinetricarboxylic acid (H3pta) with d 9 (Cu2+) and d 10 (Zn2+,Ag+) ions in water at room temperature. The complexes of [Cu(H2pta)2(H2O)2]·2H2O (1) and [Zn2(Hpta)2(H2O)6]·4H2O (2) are mononuclear and binuclear structures, respectively; while [Ag(H2pta)(H2O)] n (3) is a helical 1D chain coordination polymer. A double chain was further formed in 3 by the weak interaction between oxygen atoms and Ag(I) ions. Through hydrogen bonds the three complexes constructed corresponding 3D network structures. The three complexes were characterized by elemental analyses, IR and single-crystal X-ray diffraction analyses. In addition, TGA, XRD and fluorescence spectra determinations were performed for compounds 2 and 3. [Copyright &y& Elsevier]

• Two ionic cuprous complexes with thermally activated delayed fluorescence were synthesized. • Both complexes exhibit high contributions of TADF (83 and 80%, respectively) and PLQYs (47.5 and 60.5%, respectively) in the solid state at ambient temperature. • The small exchange energy caused by the pronounced spatial separation between HOMOs and LUMOs leads to a small Δ E ST and TADF at ambient temperature. • The OLEDs based on both complexes exhibit good performance and very mild efficiency roll-off. Herein two novel ionic cuprous complexes [Cu(POP)(Pytzb)]BF 4 (Cu1 , POP = bis(2-diphenylphosphinophenyl)ether, Pytzb = 2-(1-(benzyl)-1H-1,2,3-triazol-4-yl)pyridine) and [Cu(Xantphos)(Pytzb)]BF 4 (Cu2 , Xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene) have been synthesized in reasonable yields, and their crystal structure, UV absorption and photoluminescent properties, as well as electrochemical behaviors were investigated. At 300 K, both Cu1 and Cu2 in solid state exhibit outstanding green luminescence peaked at 533 and 526 nm, respectively, with significantly high photoluminescent quantum yields (PLQYs, 47.5 and 60.5%, respectively). Detailed exploration of emission decay times for Cu1 and Cu2 in dependence of temperature demonstrates that the two complexes are typical thermally activated delayed fluorescence (TADF) materials at ambient temperature with TADF proportions of 83 and 80%, respectively. The two complexes were employed as dopants in solution-processed electroluminescent devices. Thermally activated delayed fluorescence (TADF) of two new ionic cuprous complexes bearing 1,2,3-triazole ligand has been realized. Especially, both complexes exhibit high contributions of TADF (83 and 80%, respectively) and PLQYs (47.5 and 60.5%, respectively) in the solid state at ambient temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

With the assistance of EDTA, two fluorescence LaVO 4 :Eu 3+ materials have been synthesized via the one-step hydrothermal strategy under different pH conditions, i.e. monoclinic LaVO 4 :Eu 3+ microspheres (pH = 3) and tetragonal LaVO 4 :Eu 3+ microbundles (pH = 9). Based on series of time-dependent experiments, formation mechanisms of two products have been investigated in detail and proposed in this work. Optical characterizations conform that the luminescence property of LaVO 4 :Eu 3+ materials can be greatly affected by the structure of LaVO 4 matrixes. Meanwhile, it is found that the fluorescence property of both LaVO 4 :Eu 3+ products could be rapidly and sensitively quenched by Fe 3+ ions in water, and the quenching effect strongly depends on the concentration of Fe 3+ ions, not the crystal structure of LaVO 4 :Eu 3+ phosphors. Consequently, both the LaVO 4 :Eu 3+ products obtained in this work are considered as appropriate functional materials for sensitively and rapidly detecting the Fe 3+ ions in water. [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 novel lanthanide−sulfate compounds, [Ln 2 (SO 4 ) 3 (H 2 O) 8 ] (Ln = Tb ( 1 ) and Dy ( 2 )), have been synthesized under hydrothermal reactions. X-ray crystal structure analyses reveal that 1 and 2 are isomorphous and crystallize in monoclinic C 2 /c pace group, showing a layered structure. The layers bear a rare quasi-honeycomb metal arrangement, which is fastened by μ 3 = η 1 : η 1 : η 1 and μ 2 = η 1 : η 1 sulfates. If assigning the μ 3 = η 1 : η 1 : η 1 sulfate as a 3-connected node and the Ln 3+ ion as a 4-connected node, the network can be rationalized as a binodal (3,4)-connected V 2 O 5 topology with a Schäfli symbol of (4 2 ·6 3 ·8) (4 2 ·6). In addition, the infrared, thermogravimetric analysis and luminescent properties were also studied. Complexes 1 and 2 exhibit outstanding thermal stability and characteristic terbium and dysprosium luminescence. [ABSTRACT FROM AUTHOR]

Ni(L)2 (1) and Zn2(μ-OL)2(L)2 (2), (HL=S-benzyl-β-N-(2-bromobenzylidene) dithiocarbazate), were synthesized and characterized by elemental analysis and X-ray single-crystal diffraction analysis. 1 is a mononuclear neutral nickel(II) complex and the center nickel atom is chelated by donors of N2S2 possessing a distorted tetrahedral configuration, while in 2, the adjacent two complex molecules are linked through two O atoms to form a dimer and the center zinc atom is five-coordinate in a distorted trigonal-bipyramidal geometry. The cytotoxic activity study indicated that 2 showed potent cytotoxic activity against the human liver hepatocellular carcinoma (HepG2) cancer cell lines, with IC50 2.4±0.2μg·mL−1, which is slightly weaker than 5-fluoroacil (5-FU) (0.89±0.21μg·mL−1) as reference. A gel electrophoresis assay demonstrated the ability of the complex to cleave the pBR322 plasmid DNA. [ABSTRACT FROM AUTHOR]

Four transition metal complexes with Schiff base and 1,10-phenanthroline, [Cu(L)(phen)]2·C2H5OH (1), [Zn(L)(phen)]2·C2H5OH (2), [Ni(L)(phen)]2·C2H5OH (3), and [Co(L)(phen)]2·C2H5OH (4) (H2L = 1-((2-hydroxynaphthalen-1-yl)methylene)thiosemicarbazide; phen = 1,10-phenanthroline) were synthesized and characterized by physico-chemical methods. The crystal structure of1was determined by X-ray single-crystal diffraction analysis.1crystallizes in the orthorhombic space groupPbcawitha = 15.008(9),b = 16.100(10),c = 37.54(2) Å,V = 9070(10) Å3,Z = 8,GOOF = 1.002,R1 = 0.0626, andwR2 = 0.0912. The fluorescence and urease inhibitory activities of the compounds were tested. The enzymatic activity study indicated that3possessed potent inhibition againstjack beanurease, with IC50 = 1.2 ± 0.1 μM, and about 35 times more than 42.1 ± 0.4 acetohydroxamic acid as positive reference. This suggests that inhibitory efficiency of these complexes can be strongly influenced by different transition metal ions. [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]