92 research outputs found
Optical properties and the dispersion parameters of new zinc Phthalocyanine benzofuran derivative prepared by non-vacuum spin coating technique
The optical properties of 2(3),9(10),16(17),23(24)-tetrakis-{6-(-benzofuran-2-carboxylate)-hexylthio} phthalocyaninatozinc(II) {Zn[Pc(b-S(CH2)(6)OCOBz-furan)(4)], (ZnPcBzF) thin film prepared by spin coating method were investigated. The optical constants of the prepared film were determined using spectrophotometric measurements of the transmittance and reflectance at normal incidence in the spectral range 200-800 nm. The analysis of the spectral behavior of the absorption coefficient in the intrinsic absorption region revealed two direct allowed optical band gap of 2.58 and 3.87 eV. The dispersion of the refractive index was discussed in terms of the single oscillator using Sellmeier dispersion formula. The high frequency dielectric constant (epsilon(infinity)) and the lattice dielectric constant (epsilon(L)) were estimated. From the optical constants analysis, the optical conductivity was also considered. Discussion of the obtained results and their comparison with the previous published data were also given. The obtained results of this new zinc phthalocyanine benzofuran derivative (ZnPcBzF) support the desirable feature for the microelectronic and optoelectronic devices. (c) 2012 Elsevier B.V. All rights reserved
Fluorescent chemosensor for Ag(I) based on amplified fluorescence quenching of a new phthalocyanine bearing derivative of benzofuran
A fluorescent chemosensor for Ag(I) as a new family of peripherally functionalized zinc-phthalocyanine, 2(3),9(10),16(17),23(24)-tetrakis-{6-(-benzofuran-2-carboxylate)-hexylthio} phthalocyaninatozinc(II) [Zn[Pc(beta-S(CH2)(6)OCOBz-furan)(4)], (ZnPcBzF). (3), which was derivated from 6-(3,4-dicyanophenylthio)-hexyl-2-benzofuranate (BzF), (2), has been synthesized and fully characterized by elemental analysis, FT-IR, H-1 and C-13 NMR, MS (ESI and Maldi-TOF). An optical silver ion (Ag(l)) sensor based on the fluorescence quenching of benzofuran moiety and ZnPc core was developed. Both absorbance and fluorescence spectra of ZnPcBzF, (3) exhibit distinct changes in visible region in response to treatment with Ag(l) ion in solution. Such properties make compound ZnPcBzF, (3) intriguing candidates for incorporation into the transducer layer in optically based chemical sensors. (C) 2009 Elsevier Ltd. All rights reserved
Alcohol-soluble functional vic-dioxime bearing alcoholhexylsulfanyl moieties: preparation, spectroscopy and electrochemistry
A new alcohol soluble functionalized vic-dioxime, bis-[(1-hydroxyhexyl)-(8,9-hydroxyimino)-7,10-dithiahexacosane (LH2), and its alcohol-soluble mono and dinuclear complexes (Ni-II, Cu-II, Co-II, Mn-II, Pd-II and UO2II) have been prepared from 6-mercapto-1-hexanol and (E,E)-dichloroglyoxime under high dilution basic conditions. Reactive polyalcohol moieties appended at the periphery of the oxime containing two different heteroatoms (S-, O-), serve as a weak exocyclic binding sites for Pd (II) and Ag (I) metal ions and also provide solubility for the vic-dioxime complexes in low molecular-weight alcohols. Both mono-nuclear (LH)(2)M and homodinuclear (LH)(2)(UO2)(2)(OH)(2) and heterotrinuclear (LH)(2)MM(2)(')Xn, where M = Co-II M' = Pd-II, X = Cl-, n = 4 and Ag-I X = NO3-, n = 2) complexes have been obtained with a 1:2, 2:2, 3:2 metal/ligand ratio, respectively. Electronic spectra of the modified vic-dioximes exhibit monitorable changes in UV. All mono and dinuclear-complexes are soluble in common organic solvents. The elemental analysis, H-1-n.m.r, i.r., u.v-vis, and f.a.b.-m.s data and by cyclic and differential pulse voltammetry measurements are presented
Inorganic-organic photodiodes based on polyaniline doped boric acid and polyaniline doped boric acid:nickel(II) phthalocyanine composite
The electronic and photovoltaic properties of hybrid organic photodiodes based on n-Si/boric acid doped polyaniline (PANIB) and n-Si/2,3,7,8,12,13,17,18-octakis(2'-aminophenylsulfanyl)-substituted-nickel(II) phthalocyanine: boric acid doped polyaniline (PANIB-PC) composite have been investigated. The current-voltage characteristics of the n-Si/PANIB and n-Si/PANIB-PC diodes were analyzed under dark and illumination conditions. The open circuit voltage, V-oc and short circuit current, I-sc values for the n-Si/PANIB and n-Si/PANIB-PC diodes under 105 mW/cm(2) were respectively found to be 0.280 V, 6.19 nA and 0.304 V, 0.091 nA. The fabricated inorganic/organic devices can be used as an optical sensor for optoelectronic applications. (C) 2009 Elsevier B.V. All rights reserved
Synthesis and properties of copper(II) phthalocyanines with monoazacrown and crown ethers as peripheral substituents
Soluble and less soluble phthalocyaninatocopper(II) derivatives (4a and 4b) were prepared from the corresponding 7-[(4'-benzo-15-crown-5)oyl]-15, 16-dibromo-2,3,6,7,8,9,11,12-octahydro-5H-benzo[e]-12-octahydro-5H-benzo[e]-[1,4,10,13,7] tetraoxaazacyclopentadecine (3a) and 7-(2'-tosylaminoethyl)-15, 16-dibromo-2,3,6,7,8,9,11,12-octahydro-5H-benzo[e]-[1,4,10,13,7] tetraoxaazacyclopentadecine (3b) and CuCN in pyridine. A less soluble novel multifunctionalized scorpiand macrocycle-substituted phthalocyanine (4c) in which an NH2CH2CH2- chain is appended to a monoazacrown ether ring was obtained by detosylation of 4b with concentrated sulfuric acid. Copyright (C) 1999 John Wiley & Sons, Ltd
A vic-dioxime ligand bearing fluorescent coumarin moieties and its complexes; preparation, spectroscopy, and electrochemistry
The synthesis of a new vic-dioxime ligand, N,N'(2)-dihydroxy-O-1,O-2-bis(4-methyl-2-oxo-2H-chromen-7-yl)oxalimidamid (LH2) (1), bearing functional coumarins and its soluble mono- {Ni(II), Cu(II), Co(II)} and dinuclear {UO2(II)} complexes are presented. The fluorescence properties due to the 7-hydroxy-4-methylcoumarin fluorophore, which is conjugated with vic-dioxime that functions as the MN4 core of 1 and its complexes, are also reported. The formation of coordination complexes resulted in the blue shift in excitation spectrum and fluorescence quenching of 1. Both mononuclear {(LH)(2)M, M=Ni(II), Cu(II), and Co(II)} and homodinuclear {(LH)(2)(UO2)(2)(OH)(2))} complexes have been obtained with metal : ligand ratios of 1 : 2 and 2 : 2, respectively. The characterizations of the new compounds were made by elemental analysis, H-1-NMR, FT-IR, UV-Vis, and LCMS data. Redox behavior of 1, involving oxime and coumarin moieties, and its complexes with Ni(II), Cu(II), Co(II) and UO2(II) were investigated by cyclic voltammetry. The comparison of the electrochemical behavior of 1 with its complexes enabled us to identify metal-, oxime- and coumarin-based signals
Fluorescent vic-dioxime-type ligand and its mono- and dinuclear complexes: The preparation, spectroscopy, and electrochemistry of its various complexes
A new coumarin functionalized vic-dioxime, S,S-bis-[4-methylcoumarinyl]-dithioglyoxime (LH2), and its soluble mono- and dinuclear complexes [nickel(II), copper(II), cobalt(II), and uranyl(II)] have been reported. The fluorescent properties of the ligand and its complexes are due to the 7-mercapto-4-methylcoumarin fluorophore, which is conjugated with vic-dioxime that functions as the MN4 core. Fluorescence spectra of the probe showed a clear shift in excitation wavelength maxima upon metal binding indicating its potential use as ratio-metric metal indicator. The fluorescence of complexes was found to be highly sensitive to both polarity and protic character of the solvent used. Both mononuclear (LH)(2)M (M = Ni, Cu and Co) and homodinuclear (LH)(2)(UO2)(2)(OH)(2)) complexes have been obtained with the metal ligand ratios of 1:2 and 2:2, respectively. The characterizations of all newly synthesized compounds were made by elemental analysis, H-1 NMR, FT-IR, UV-vis, and mass (LSI-MS) data. The electrochemical investigation of the Ni(II), Cu(II), Co(II) and UO2(II) Complexes in comparison with the ligand involving oxime and coumarin moieties enabled us to identify metal-, oxime- and coumarin-based signals. (C) 2006 Elsevier Ltd. All rights reserved
Coumarin-derivatized fluorescent vic-dioxime-type ligand and its complexes; the preparation, spectroscopy, and electrochemistry
A new vic-dioxime bearing coumarin functionality, N-'1, N-'2-Dihydroxy-N1, N2-bis(4-methyl-2-oxo-2H-chromen-7yl) oxalimidamid (LH2), N,N-bis-[4-methylcoumarinyl]-diamino glyoxime (LH2), and its mono- and dinuclear complexes {copper(II), cobalt(II), nickel(II) and uranyl(II)} have been reported. The. uorescence excitation and emission spectra of LH2 and its complexes with metal ions were examined. It was observed that. uorescence and excitation emission intensity of LH2 was quenched depending on complex formation with metal ions. The characterizations of all newly synthesized compounds were made by elemental analysis, H-1-n.m.r,i.r.,u.v.-vis., and l.c-m.s. m.s. data. Electrochemical behaviour of the ligand involving oxime and coumarine moieties, and its complexes with Ni-II, Cu-II, Co-II and UO2II were investigated by cyclic voltammetry. The comparison of the electrochemical behaviour of the ligand with its complexes enabled us to identify metal-, oxime- and coumarine-based signals
Effects of coumarin substituents on the photophysical properties of newly synthesised phthalocyanine derivatives
In this study, synthesis of new ligands, 8-hydroxy-3-[p-(3',4'-dicyanophenoxy)-phenyl]coumarin and 8-hexyloxy-3-[p-(3',4'-dicyanophenoxy)-phenyl]coumarin, and their phthalocyanines, 2,9,16,23-tetrakis[8-hexyloxy-3-(4-oxyphenyl)coumarin]-metal-free and metallophthalocyanines {M[Pc(OBzCou)4] (M=2H, Zn(II), Co(II); Bz: benzene; Cou: coumarin)} were synthesised. The novel chromogenic compounds were characterised by elemental analysis: 1H NMR, 13C NMR, MALDI-TOF, IR and UV-vis spectral data. The effect of coumarin substituents on the photophysical properties of metal-free (H2Pc) and zinc phthalocyanines (ZnPc) derivatives has been examined. Spectrophotometric measurements revealed that coumarin-substituted ZnPc derivatives were in the unaggregated form, whereas those of H2Pc species were in aggregated form. It means that substitution of coumarin derivative prevents the cluster formation in the presence of zinc ion in the centre of Pc
Synthesis, characterization and fluorescence behavior of new fluorescent probe phthalocyanines bearing coumarin substituents
In this study, we report a new ligand, 6-hexyloxy-3-[p-(3',4'-dicyanophenoxy)phenyl]coumarin, and its fluorescent tetrasubstituted phthalocyanines {M[Pc(OBzCou)(4)], M =2H, Zn(II), Co(II); Bz: Benzene}. The effect of the coumarin derivative oil the intensity of the fluorescence spectra of the metal-free (H2Pc) and zinc phthalocyanine (ZnPc) derivatives was investigated. The change of the emission properties of both the coumarin moieties and the phthalocyanine core in the presence of the metal ion and the ring-opening reaction of the coumarin were studied by means of steady-state fluorescence spectroscopy. The radiative decay of the Pcs and the treated coumarin substituents bound to the Pcs was examined. The novel chromogenic compounds were characterized by elemental analysis, H-1 NMR,C-13 NMR, Maldi-TOF, IR and UV-Vis spectral data. The photophysical properties of the Pcs are extensively affected by their state of aggregation: in particular, dimerization and aggregation result in a remarkable modification of the absorption and emission bands and may induce significant quenching of the usually strong Pc fluorescence. The electronic spectra exhibit a band of coumarin identity together with characteristic Q and B bands of the phthalocyanine core. (c) 2008 Elsevier Ltd. All rights reserved
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