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Eu3+ Ions (eu3+ + ion)

Distribution by Scientific Domains
Chemistry72%
Polymers and Materials Science27%

Selected Abstracts

ZnO:Eu Thin-Films: Sol,Gel Derivation and Strong Photoluminescence from 5D0 , 7F0 Transition of Eu3+ Ions.

CHEMINFORM, Issue 24 2007
Peiliang Chen
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

EuIII -Doping of Lamellar Bilayer and Amorphous Mono-Amide Cross-Linked Alkyl/Siloxane Hybrids

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2010
Silvia C. Nunes
Abstract Two structurally different but chemically similar families of alkyl/siloxane mono-amidosil hosts, represented by m-A(x) [where x = 14 or 8 represents the number of CH2 groups of the pendant alkyl chains directly bonded to the carbonyl group of the amide cross-link] have been doped with a wide range of concentrations of Eu(CF3SO3)3. Mono-amidosils m-A(x)nEu(CF3SO3)3 with n,,,10 (where n is the molar ratio of carbonyl groups per Eu3+ ion) have been analyzed. The m-A(8)nEu(CF3SO3)3 mono-amidosils are transparent and amorphous films, in which the alkyl chains adopt gauche conformations. In contrast, the m-A(14)nEu(CF3SO3)3 mono-amidosils are solid powders; here the lamellar bilayer hierarchical structure of m-A(14) coexists with a new lamellar phase in which the Eu3+ ions are bonded to carbonyl oxygen atoms of the amide groups. At n = 10 the hydrogen-bonded associations formed are highly ordered and considerably stronger than those found in the less concentrated hybrids and in the nondoped matrices. "Free" and weakly coordinated triflate ions occur in all the mono-amidosil samples. The hybrids are white light emitters (maximum quantum yield: 0.08,±,0.01), presenting a broad emission band in the blue/purplish-blue spectral region (ascribed to the hybrid host) superimposed on the 5D0,7F0,4 Eu3+ intra-4f6 transitions. Two Eu3+ local coordination sites (named A and B) have been discerned in both systems. Site A is attributed to weakly coordinated Eu3+/CF3SO3, ion pairs, whereas site B involves Eu3+ coordination to the oxygen atoms of the C=O groups, of the CF3SO3, ions and of the water molecules. For site B, the long-range order of the hybrid host induces distinct features in the energy of the 5D0,7F0,4 transitions, the 5D0 lifetime and the degree of covalency of the Eu3+,first-ligand bonds. [source]

Spectroscopic Investigation of the Europium(3+) Ion in a New ZnY4W3O16 Matrix

HELVETICA CHIMICA ACTA, Issue 11 2009
bieta Tomaszewicz
Abstract A new Zn and Eu tungstate was characterized by spectroscopic techniques. This tungstate, of the formula ZnEu4W3O16, crystallized in the orthorhombic system and was synthesized by a solid-state reaction. It melts incongruently at 1330°. The luminescent properties, including excitation and emission processes, luminescent dynamics, and local environments of the Eu3+ ions in ZnEu4W3O16 and ZnY4W3O16,:,Eu3+ diluted phases (1, 5, and 10,mol-% of Eu3+ ion) were studied basing on the f6 -intraconfigurational transitions in the 250,720,nm spectral range. The excitation spectra of this system (,em 615 and 470,nm) show broad bands with maxima at 265 and 315,nm related to the ligand-to-metal charge-transfer (LMCT) states. The emission spectra under excitation at the O,W (265,nm) and O,Eu3+ (315,nm) LMCT states present the blue-green emission bands. The emission of tungstate groups mainly originate from the charge-transfer state of excited 2p orbitals of O2, to the empty orbitals of the central W6+ ions. On the other hand, in the emission of the Eu3+ ions, both the charge transfer from O2, to Eu3+ and the energy transfer from W6+ ions to Eu3+ are involved. The emission spectra under excitation at the 7F0,5L6 transition of the Eu3+ ion (394,nm) of ZnY4W3O16,:,Eu3+ diluted samples show narrow emission lines from the 5D3, 5D2, and 5D1 emitting states. The effect of the active-ion (Eu3+) concentration on the colorimetric characteristic of the emissions of the compound under investigation are presented. [source]

Minocycline-Based Europium(III) Chelate Complexes: Synthesis, Luminescent Properties, and Labeling to Streptavidin

HELVETICA CHIMICA ACTA, Issue 11 2009
Takuya Nishioka
Abstract Two chelate ligands for europium(III) having minocycline (=(4S,4aS,5aR,12aS)-4,7-bis(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxonaphthacene-2-carboxamide; 5) as a VIS-light-absorbing group were synthesized as possible VIS-light-excitable stable Eu3+ complexes for protein labeling. The 9-amino derivative 7 of minocycline was treated with H6TTHA (=triethylenetetraminehexaacetic acid=3,6,9,12-tetrakis(carboxymethyl)-3,6,9,12-tetraazatetradecanedioic acid) or H5DTPA (=diethylenetriaminepentaacetic acid=N,N -bis{2-[bis(carboxymethyl)amino]ethyl}glycine) to link the polycarboxylic acids to minocycline. One of the Eu3+ chelates, [Eu3+(minocycline-TTHA)] (13), is moderately luminescent in H2O by excitation at 395,nm, whereas [Eu3+(minocycline-DTPA)] (9) was not luminescent by excitation at the same wavelength. The luminescence and the excitation spectra of [Eu3+(minocycline-TTHA)] (13) showed that, different from other luminescent EuIII chelate complexes, the emission at 615,nm is caused via direct excitation of the Eu3+ ion, and the chelate ligand is not involved in the excitation of Eu3+. However, the ligand seems to act for the prevention of quenching of the Eu3+ emission by H2O. The fact that the excitation spectrum of [Eu3+(minocycline-TTHA)] is almost identical with the absorption spectrum of Eu3+ aqua ion supports such an excitation mechanism. The high stability of the complexes of [Eu3+(minocycline-DTPA)] (9) and [Eu3+(minocycline-TTHA)] (13) was confirmed by UV-absorption semi-quantitative titrations of H4(minocycline-DTPA) (8) and H5(minocycline-TTHA) (12) with Eu3+. The titrations suggested also that an 1,:,1 ligand Eu3+ complex is formed from 12, whereas an 1,:,2 complex was formed from 8 minocycline-DTPA. The H5(minocycline-TTHA) (12) was successfully conjugated to streptavidin (SA) (Scheme,5), and thus the applicability of the corresponding Eu3+ complex to label a protein was established. [source]

EuIII -Doping of Lamellar Bilayer and Amorphous Mono-Amide Cross-Linked Alkyl/Siloxane Hybrids

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2010
Silvia C. Nunes
Abstract Two structurally different but chemically similar families of alkyl/siloxane mono-amidosil hosts, represented by m-A(x) [where x = 14 or 8 represents the number of CH2 groups of the pendant alkyl chains directly bonded to the carbonyl group of the amide cross-link] have been doped with a wide range of concentrations of Eu(CF3SO3)3. Mono-amidosils m-A(x)nEu(CF3SO3)3 with n,,,10 (where n is the molar ratio of carbonyl groups per Eu3+ ion) have been analyzed. The m-A(8)nEu(CF3SO3)3 mono-amidosils are transparent and amorphous films, in which the alkyl chains adopt gauche conformations. In contrast, the m-A(14)nEu(CF3SO3)3 mono-amidosils are solid powders; here the lamellar bilayer hierarchical structure of m-A(14) coexists with a new lamellar phase in which the Eu3+ ions are bonded to carbonyl oxygen atoms of the amide groups. At n = 10 the hydrogen-bonded associations formed are highly ordered and considerably stronger than those found in the less concentrated hybrids and in the nondoped matrices. "Free" and weakly coordinated triflate ions occur in all the mono-amidosil samples. The hybrids are white light emitters (maximum quantum yield: 0.08,±,0.01), presenting a broad emission band in the blue/purplish-blue spectral region (ascribed to the hybrid host) superimposed on the 5D0,7F0,4 Eu3+ intra-4f6 transitions. Two Eu3+ local coordination sites (named A and B) have been discerned in both systems. Site A is attributed to weakly coordinated Eu3+/CF3SO3, ion pairs, whereas site B involves Eu3+ coordination to the oxygen atoms of the C=O groups, of the CF3SO3, ions and of the water molecules. For site B, the long-range order of the hybrid host induces distinct features in the energy of the 5D0,7F0,4 transitions, the 5D0 lifetime and the degree of covalency of the Eu3+,first-ligand bonds. [source]

Spectroscopic Investigation of the Europium(3+) Ion in a New ZnY4W3O16 Matrix

HELVETICA CHIMICA ACTA, Issue 11 2009
bieta Tomaszewicz
Abstract A new Zn and Eu tungstate was characterized by spectroscopic techniques. This tungstate, of the formula ZnEu4W3O16, crystallized in the orthorhombic system and was synthesized by a solid-state reaction. It melts incongruently at 1330°. The luminescent properties, including excitation and emission processes, luminescent dynamics, and local environments of the Eu3+ ions in ZnEu4W3O16 and ZnY4W3O16,:,Eu3+ diluted phases (1, 5, and 10,mol-% of Eu3+ ion) were studied basing on the f6 -intraconfigurational transitions in the 250,720,nm spectral range. The excitation spectra of this system (,em 615 and 470,nm) show broad bands with maxima at 265 and 315,nm related to the ligand-to-metal charge-transfer (LMCT) states. The emission spectra under excitation at the O,W (265,nm) and O,Eu3+ (315,nm) LMCT states present the blue-green emission bands. The emission of tungstate groups mainly originate from the charge-transfer state of excited 2p orbitals of O2, to the empty orbitals of the central W6+ ions. On the other hand, in the emission of the Eu3+ ions, both the charge transfer from O2, to Eu3+ and the energy transfer from W6+ ions to Eu3+ are involved. The emission spectra under excitation at the 7F0,5L6 transition of the Eu3+ ion (394,nm) of ZnY4W3O16,:,Eu3+ diluted samples show narrow emission lines from the 5D3, 5D2, and 5D1 emitting states. The effect of the active-ion (Eu3+) concentration on the colorimetric characteristic of the emissions of the compound under investigation are presented. [source]

A Novel Narrow Band Red-Emitting Phosphor for White Light Emitting Diodes

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009
Sivakumar Vaidyanathan
Research on down conversion phosphor materials is the key for the development of solid-state lighting (SSL). Especially finding alternative red phosphor for white light emitting diodes (LEDs) based on blue or near ultraviolet (NUV) LEDs is important research task. In this view, we have synthesized a series of Eu3+ -substituted La2W2,xMoxO9 (x=0,2, in step of 0.3) red phosphor and characterized by X-ray diffraction (XRD) and photoluminescence. XRD results reveal a phase transition from triclinic to cubic structure for x>0.2. All the compositions show broad charge transfer (CT) band due to CT from oxygen to tungsten/molybdenum and red emission due to Eu3+ ions. Select compositions show high red emission intensity compared with the commercial red phosphor under NUV/blue ray excitation. Hence, this candidate can be a possible red phosphor for white LEDs. [source]

Formation of Europium Chelate Complexes by Vacuum Co-Deposition and Their Application in Organic Light-Emitting Diodes,

ADVANCED MATERIALS, Issue 13 2004
T. Oyamada
A unique method of material synthesis based on vacuum co-deposition is reported. A Eu complex was formed by co-deposition of bis(dipivaloymethanato)europium (Eu(DPM)3) and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), which both showed excellent volatility during vacuum deposition. Photoexcitation of the BCP led to intense emission from the Eu3+ ions, verifying efficient exciton energy transfer and therefore complex formation. [source]

Spectroscopic Properties and Local Structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) Glasses

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2003
Woon Jin Chung
Spectroscopic properties and local structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) glasses were investigated using fluorescence measurements and several spectroscopic methods. Fluorescence from Eu3+:5D0,7F2 was observed only from glasses with CsBr/Ga ratios greater than unity and disappeared at temperatures above 140 K. Phonon sideband (PSB) spectra revealed that Eu3+ ions are located next to halogen ions, which form part of well-structured complexes such as EuCl3, tetrahedral [GaS3/2Cl],, subunits and/or Ga2Cl6. These new bonds showed reduced coupling strength compared with Eu3+,S bonds in Ge,Ga,S glass. Fluorescence line narrowing experiments showed little site-to-site variation of Eu3+ ions. [source]

Luminescent organo-polysiloxanes containing complexed lanthanide ions

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2009
Lei Liu
Abstract In this study, a type of polysiloxane with the ester as the functional side group was prepared via a hydrosilylation reaction. The functionalized polysiloxane was then allowed to complex with Tb3+ and Eu3+ ions. Fourier transform infrared, ultraviolet absorption spectra and 1H-NMR, 13C-NMR and 29Si-NMR spectra were used to confirm the modification. Differential scanning calorimetry and thermal gravity analysis were used to study the polysiloxane's thermal properties. The complexes' luminescence spectra were recorded, and narrow-width green and red emissions were achieved. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Synthesis and Optical Properties of Europium-Complex-Doped Inorganic/Organic Hybrid Materials Built from Oxo,Hydroxo Organotin Nano Building Blocks

CHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2010
Wei-Qiang Fan Dr.
Abstract Hybrid materials doped with novel europium complexes were synthesized using PMMA- co -Sn12Clusters (copolymers from oxohydroxo-organotin dimethacrylate and methylmethacrylate) as the matrix material. Two types of hybrid materials were obtained: the physically doped product, PMMA- co -Sn12Cluster/Eu(TTA)3phen, and the grafted product, PMMA- co -Sn12Cluster- co -[EuAA(TTA)2phen] (TTA=2-thenoyltrifluoroacetone, phen=phenanthroline and AA=acrylic acid). The hybrid materials exhibited characteristic luminescence of the Eu3+ ions, and also showed relative especial optical properties compared with samples just using PMMA as the matrix material. The PMMA- co -Sn12Cluster matrix exhibited a high physical doping quantity of [Eu(TTA)3phen], which can be attributed to the special structure of this kind of hybrid material. GPC (gel-permeation chromatography), TGA (thermogravimetric analysis), SEM, 1H,NMR, ICP (inductively coupled plasma), 119Sn,NMR, FTIR, and diffuse reflectance techniques were employed to characterize the structures and properties of these hybrid materials. [source]