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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 254: 119588, 2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-33743311

RESUMEN

Five diverse 1D supramolecular chains, {[4-pmntd]}n(1), {H2[4-pmntd]•2Br-}n(2), {H2[4-pmntd]•2NO3-}n(3), {H2[4-pmntd]•2ClO4-}n(4), {H2[4-pmntd]•2BF4-}n(5), (where 4-pmntd was N,N'-bis (4-pyridylmethyl)naphthalene diimide) were synthesized and characterized by X-ray single-crystal structure analysis, IR spectroscopy, elemental analyses, thermogravimetric analyses, fluorescence detection. The anions effect construction of their 1D chain structural diversity through different π interactions. Compound 1 through the adjacent pyridine rings parallel π∙∙∙π interactions formed 1D linear chain structure. Compound 2 through Br- anion∙∙∙π interactions and halogenbond interactions formed 1D zigzag chain structure. Compound 3 through lone pair∙∙∙π interactions of naphthalene diimide and the adjacent carboxyl group formed 1D stairway chain structure. Compound 4 through ClO4- anion∙∙∙π interactions formed 1D ribbon chain structure. Compound 5 through parallel π∙∙∙π interactions of the adjacent naphthalene diimide planes and pyridine rings formed 1D ladder chain structure. The five compounds' fluorescence properties and thermal stabilities were investigated. The compound 2 solution could fluorescence detection for iodide anion via fluorescence quenching.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117941, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31884400

RESUMEN

Three diverse supramolecular compounds, {[3-pmpmd]}n(1), {H2[3-pmpmd]·2NO3-}n(2), {H2[3-pmpmd]·2tbb}n(3), (where 3-pmpmd was N,N'-bis(3-pyridylmethyl)pyromellitic diimide; tbb was tertiary butyl benzoic acid) were synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X-ray single-crystal structure analysis. The co-crystal anions affect their structural diversity. Compound 1 is a 1D stairway chain structure by perpendicular π⋯π interactions of pyromellitic diimide and the neighboring pyridine rings. Compound 2 is a typical 1D ladder chain structure by hydrogen bond of nitrate arranged in a parallel array. Compound 3 is a 1D zigzag chain structure of one 3-pmpmd and two tbb by parallel π⋯π interactions and hydrogen bond interactions. Thermal stabilities and fluorescence properties of all compounds were investigated. The solution of compound 2 in DMF can fluorescence sense for iodide ions by remarkably quenching fluorescence intensity.

3.
ACS Omega ; 4(1): 1995-2000, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31459450

RESUMEN

The selective separation of ethanol/acetonitrile by porous materials has rarely been observed owing to their similar physicochemical properties. In this work, we report a new coordination network, [Cu2(4-pmntd)2(opd)2](4-pmntd = N,N'-bis(4-pyridymethy)naphthalene diimide, opd = disodium 1,2-benzenedicarboxylate), which exhibits selective separation of ethanol over acetonitrile. The weak coordination bonds formed by unsaturated Cu2+ sites and hydroxyl groups are the key to such performance.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 187: 168-173, 2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-28686918

RESUMEN

Two complexes, {[Mn(3-pmpmd)2(Cl)2]·2H2O}n(1), {[Cd(3-pmpmd) (I)2]·CHCl3·H2O}n(2), (3-pmpmd, N,N'-bis(3-pyridylmethyl)pyromellitic diimide) were synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X-ray single-crystal structure analysis. The conformations of 3-pmpmd ligand affect their structural diversity. Complex 1 is a 1D double chain structure in edge-to-edge arrangement by π⋯π interactions. Complex 2 is a typical 1D zigzag chain structure arranged in a parallel array containing 1D channel to accommodate the chloroform and water guest molecules. Thermal stabilities and fluorescence properties of both complexes were investigated. The solution of complex 2 in DMF can sense for I- anion by quenching fluorescence intensity, whereas other anions increasing fluorescence intensity.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 103: 417-22, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23274226

RESUMEN

A new ß-diketone ligand, 1-(4-ethyl-4H-thieno[3,2-b]indol-6-yl)-4,4,4-trifluoro-butane-1,3-dione(HL) was synthesized by four steps reaction (Suzuki-Miyaura cross-coupling, Cadogan cyclization, N-ethylation and Claisen condensation reaction) from 1-(4-bromo-3-nitrophenyl)ethanone and thiophen-2-ylboronic acid. Deprotonated ligand (L(-1)) and 1,10-phenanthroline (phen) coordinated to Eu(3+) to obtain a new europium (III) complex, EuL(3)(phen). The complex was characterized by elementary analysis, IR, (1)H NMR, UV-Visible absorption spectroscopy, thermogravimetric analysis (TGA) and photoluminescence (PL) measurements in detail. TGA shows that the decomposition temperature of the complex is up to 320 °C. PL measurement results indicate that the Eu(III) complex exhibit intense red-emission with the characteristic of europium ion. Red LED device was successfully fabricated by employing the complex onto 380 nm-emitting InGaN chip, which shows that the complex can act as red phosphor in combination with 380 nm-emitting chips.


Asunto(s)
Complejos de Coordinación/química , Europio/química , Fenantrolinas/química , Butanos/síntesis química , Butanos/química , Complejos de Coordinación/síntesis química , Ciclización , Halogenación , Cetonas/síntesis química , Cetonas/química , Ligandos , Luminiscencia , Espectroscopía de Resonancia Magnética , Fenantrolinas/síntesis química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Tiofenos/síntesis química , Tiofenos/química
6.
Artículo en Inglés | MEDLINE | ID: mdl-22824517

RESUMEN

Two cadmium complexes, Cd(bpbp)Cl(2) (complex 1) and [Cd(bpbp)(2)](ClO(4))(2) (complex 2), based on 2,6-bis(1-phenylbenzimidazol-2-yl)pyridine (bpbp), were synthesized and characterized by X-ray single crystal structure analyses. For complex 1: crystal system, monoclinic, space group, C2/c, a=27.427(3)Å, b=13.4495(15)Å, c=14.8381(17)Å, ß=106.635(2)°, V=5244.4(10)Å(3), Z=8. It is a neutral complex. The Cd(II) ion distorted trigonal bipyramidal geometry is five-coordinated by three nitrogen atoms from ligand (bpbp) and two chlorine ions. For complex 2: crystal system, triclinic, space group, P-1, a=13.4791(15)Å, b=13.8506(16)Å, c=16.5839(19)Å, α=94.202(2)°, ß=106.948(2)°, γ=94.872(2)°, V=2935.3(6)Å(3), Z=2. It is an ionic complex. The Cd(II) ion octahedral geometry is six-coordinated by six nitrogen atoms from two ligand (bpbp). Both complexes emit blue luminescence with emission peaks at 420 and 430 nm in solid state and with emission peaks at 415 and 425 nm in DMF solution. In complex 1 absorption spectra, there is not only the free ligand absorption peak at 310 nm, but also shows strong Cd-Cl charge transfer peak at 350 nm in DMF solution.


Asunto(s)
Bencimidazoles/química , Bencimidazoles/síntesis química , Cadmio/química , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Piridinas/química , Piridinas/síntesis química , Cationes , Cristalografía por Rayos X , Dimetilformamida/química , Hidrógeno/química , Ligandos , Luminiscencia , Soluciones , Espectrometría de Fluorescencia , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 612-5, 2010 Mar.
Artículo en Chino | MEDLINE | ID: mdl-20496671

RESUMEN

A new europium (III) complex, EuL3 phen, [HL = 4,4,4-trifluoro-1-(4'-m-terphenyl)-1,3-butanedione, phen = 1, 10-phenanthroline] was synthesized. Its structure was characterized by elemental analysis, IR and FAB-MS. The complex exhibits strongly red emission due to the 5D0-7F(J) (J = 0-4) transitions of Eu3+ ions under irradiation of UV or 395 nm emission light of InGaN chip. The strongest emission peak is located at 613 nm. The luminescence quantum yield is 13%. The lifetime of the complex is 470 micros. The decay curve can be fit with a single exponential. The thermogravimetric analyses curve for the complex shows that the complex is stable up to 220 degrees C, which meets the requirement of fabrication of LED device. A red luminescent LED was successfully fabricated by coating complex EuL3 phen onto 395 nm emitting InGaN chip. The mass ratio of complex to the silicone is related to the chromaticity coordinates and efficiency of fabricated LED. When the mass ratio of complex to the silicone is 1 : 25, the chromaticity coordinates of the fabricated LED with the europium complex are x = 0.64 and y = 0.35 and the efficiency achieves 0.89 lm x W(-1). The results indicate that the complex may act as a potential red component in the fabrication of white LEDs.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 74(3): 731-4, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19726223

RESUMEN

Complex Eu(dbt)(3)(phen) (Hdbt=2-(4', 4', 4'-trifluoro-1', 3'-dioxobutyl)-dibenzothiophene, phen=1,10-phenanthroline) was synthesized. The complex emits red luminescence, characteristic of the (5)D(0)-->(7)F(J) (J=0-4) emission bands of Eu(3+) under near ultraviolet. A red conversion light-emitting diode (LED) device was fabricated by coating complex onto InGaN-based-LED chip that emits 395nm ultraviolet light. When the mass ratio of the red phosphor to the silicone is 1:25, the LED device's CIE chromaticity coordinates are x=0.5835, y=0.2857, and the luminescence efficiency is 1.29 lm/w. All the results show that this europium complex may act as a red component in fabrication of white LEDs with high color-rendering index.


Asunto(s)
Europio/química , Tiofenos/química , Luz , Luminiscencia , Óptica y Fotónica
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