Hydrothermal synthesis and X-ray single crystal structure of bimetallic cluster complex [{Co(phen)(2)}(2)V4O12]center dot H2O

A new bimetallic cluster complex with the formula [{Co(phen)(2)}(2)V4O12](H2O)-H-. was synthesized from the hydrothermal reaction of V2O5, H2C2O4, Co(NO3)(2), 1,10-phenanthroline (phen), (C4H9)(4)NOH and water. The compound crystallizes in an orthorhombic system with space group Pbcn and unit cell parameters a = 19.106(3) Angstrom, b = 15.250(3) Angstrom, c = 16.321(2) Angstrom, V = 4755.4(13) Angstrom(3), Z = 4 and R = 0.0318. The bimetallic cluster complex [{Co(phen)(2)}(2)V4O12](H2O)-H-. is composed of a discrete V4O124- cluster eovalently attached to two [Co(phen)(2)](2+) fragments and the discrete hexanuclear bimetallic clusters of [{Co(phen)(2)}(V4O12)-V-2](H2O)-H-. are further extended into interesting three-dimensional supermolecular arrays via pi-pi stacking interactions of phen groups. Other characterizations by elemental analysis, IR, and thermal analysis are also described.

Electroluminescence based on a beta-diketonate ternary samarium complex

The triplet energy state of the HTH [HTH: 4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl) hexane-1,3-dione] ligand was measured to be 20 400 cm(-1), which indicated that Sm(HTH)(3) phen (phen: 1,10-phenanthroline) is a good complex to produce strong PL intensity and high fluorescence yield. Electroluminescent (EL) devices using the Sm( HTH) 3 phen complex as the emissive center were fabricated by vapor deposition and spin-coating methods. The relative intensity of the EL spectra changed compared to the photoluminescence (PL) spectrum, which suggested that the luminescence mechanisms of PL and EL have differences. A luminance of 9 cd m(-2) and a higher brightness of 21 cd m(-2) were obtained from the devices ITO/TPD (40 nm)/ Sm( HTH)(3) phen (50 nm)/ PBD (30 nm)/ Al (200 nm) and ITO/PVK (40 nm)/ PVK : Sm( HTH)(3) phen (2.5 wt%, 50 nm)/ PBD (30 nm)/ Al (200 nm), respectively.

Preparation and luminescence properties of the mesoporous MCM-41s intercalated with rare earth complex

Rare earth complex Eu(DBM)(3)phen (DBM: dibenzoylmethane, phen: 1.10-phenanthroline) hits been incorporated into unmodified MCM-41 and modified MCM-41s by aminopropyltriethoxysilane (APTES) or N-[(3-triethoxysilyl)propyl]ethylenediamine(TEPED). Thus, the assemblies of unmodified or modified MCM-41s with rare earth (RE) complex have been obtained. XRD spectra. NMR spectra. diffuse reflectance spectra. and the luminescence spectra were used to characterize the pure RE complex and the corresponding assemblies. The assemblies have better luminescence properties under UV irradiation. and their fluorescence lifetimes on the excited state are longer than that of the corresponding pure complex. The possible mechanisms are also discussed in the context.

Sol-gel preparation and luminescence properties of nano-structured hybrid materials incorporated with europium complexes

Microporous silica gel has been prepared by the sol-gel method utilizing the hydrolysis and polycondensation of tetraethylorthosilicate (TEOS). The gel has been doped with the luminescent ternary europium complex Eu(TTA)(3)(.)phen: where HTTA=1-(2-thenoyl)-3,3,3-trifluoracetone and phen=1,10-phenanthroline. By contrast to the weak f-f electron absorption bands of Eu3+, the complex organic ligand exhibits intense near ultraviolet absorption. Energy transfer from the ligand to Eu3+ enables the production of efficient, sharp visible luminescence from this material. Utilizing the polymerization of methyl methacrylate, the inorganic/polymer hybrid material containing Eu(TTA)(3)(.)phen has also been obtained. SEM micrographs show uniformly dispersed particles in the nanometre range. The characteristic luminescence spectral features of europium ions are present in the emission spectra of the hybrid material doped with Eu(TTA)(3)(.)phen.

Preparation and luminescence properties of ormosil material doped with Eu(TTA)(3)phen complex

The europium complex, Eu(TTA)(3)phen (TTA = thenoyltrifluoroacetone, phen = 1,10-phenanthroline) was successfully doped into organically modified silicate (ormosil) matrix-SiO2/(VTMOS+PMMA) (VTMOS = vinyltrimethoxysilane, PMMA = polymethylmethacrylate) via sol-gel process, and the luminescence properties of the resultant ormosil composite phosphors [ormosil: Eu(TTA)(3)phen were investigated compared with those of the pure Eu(TTA)(3)phen complex powder. The ormosil composite materials incorporated with Eu(TTA)(3)phen show the characteristic red emission of Eu3+ ion. The Eu3+ possesses fewer emission lines and longer lifetime in the hybrid phosphor than in the pure Eu(TTA)(3)phen complex. This has been explained from the viewpoint of the surrounding environment where the Eu3+ ion lies. (C) 2000 Elsevier Science B.V. All rights reserved.

Preparation, characterization and photophysical properties of layered zirconium bis(monohydrogenphosphate) intercalated with rare earth complexes

Two kinds of rare earth (RE) complexes were intercalated into zirconium bis(monohydrogenphosphate) (alpha -ZrP) by exchanging the RE complexes into the p-methyoxyaniline (PMA) preintercalated compound Zr(O3POH)(2). 2PMA (alpha -ZrP . 2PMA). Powder X-ray diffraction patterns reveal that Eu(DBM)(3)phen (DBM: dibenzoylmethane, phen: 1,10-phenanthroline) and Tb(AA)(3)phen (AA: acetylacetone) intercalated into alpha -ZrP . 2PMA. This was confirmed by the UV-visible spectra of both the RE complexes and the assemblies. At the same time, the assemblies have better luminescent properties, and the fluorescent lifetimes of RE3+ in the excited state in the assemblies are much longer than those in the complexes. The stabilities of the assemblies under UV radiation are much better than those of the RE complexes.

Preparation and luminescence properties of sol-gel hybrid materials incorporated with europium complexes

Microporous silica gel has been prepared by the sol-gel method utilizing the hydrolysis and polycondensation of tetraethylorthosilicate (TEOS). The gel has been doped with the luminescent ternary europium complex Eu(TTA)(3). phen: where HTTA = 1-(2-thenoyl)-3,3,3-trifluoracetone and phen = 1,10-phenanthroline. By contrast to the weak f-f electron absorption bands of Eu3+, the complex organic ligand exhibits intense near ultraviolet absorption. Energy transfer from the ligand to Eu3+ enables the production of efficient, sharp visible luminescence from this material. Utilizing the polymerization of methyl methacrylate or ethyl methacrylate, the inorganic/polymer hybrid materials containing Eu(TTA)(3). phen have also been obtained. SEM micrographs show uniformly dispersed particles in the nanometre range. The characteristic luminescence spectral features of europium ions are present in the emission spectra of the hybrid material doped with Eu(TTA)3 phen. (C) 2000 Kluwer Academic Publishers.

Synthesis and characterization of two novel [Ru(bpy)(2)(phen)](2+)-based electrochemiluminescent labels

Two novel electrochemiluminescent labels, bis(2,2'-bipyridine)[5-(3-carboxylic acid-propionamido)1,10-phenanthroline]ruthenium(II) hexafluorophosphate dihydrate and bis(2,2'-bipyridine)[5-(4-carboxylic acid-butanamido)-1,10-phenanthroline]ruthenium(II) hexafluorophosphate dihydrate, were synthesized and confirmed by IRelemental analysis, and H-1-NMR spectra were completely assigned using the (HH)-H-1-H-1 COSY technique. Cyclic voltammograms with different scan rates showed quasireversible electrochemical behaviour of the two Ru (II) complex labels in MeCN solution. Electronic absorption, photoluminescence and electrochemiluminescence of Ru(II) complexes were also characterized. Copyright (C) 2000 John Wiley & Sons, Ltd.

A comparative study on the electroluminescence properties of some terbium beta-diketonate complexes

By comparing the phosphorescence spectra of Gd(acac)(3) (acac=acetylacetone), Gd(TFacac)3 (TFacac=1,1,1-trifluoroacetylacetone), the effects of fluorine replacement of hydrogen on the triplet state energy of the ligands were revealed. Fluorine can lower the triplet state energy of Hacac and make it more suitable for energy transfer towards the D-5(4) state of terbium. Organic electroluminescent devices (OELDs) with the corresponding trivalent terbium complexes as emissive layers were fabricated. Triple-layer-type devices with a structure of glass substrate/ITO (indium tin oxide)/PVK [poly(N-vinylcarbazole)]/PVK : Tb complex: PBD [2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole]/PBD/Al exhibit bright green luminescence upon applying a dc voltage. The luminance of a device with Tb(TFacac)(3)phen (1,10-phenanthroline) and Tb( TFacac) 3 as emissive layer is higher than that of the corresponding devices with Tb(acac)(3)(phen) and Tb(acac)(3) as emissive layers. The EL device with Tb(TFacac)(3)(phen) as emitter exhibits characteristic emission of Tb3+ ions with a maximum luminance of 58 cd m(-2) at 25 V.

Preparation and optical characterization of an organoeuropium-doped sol-gel transparent luminescence thin film

Binary and ternary europium complexes with dibenzplymethane (DBM) and 1,10-phenanthroline (phen) were synthesized and doped into a sol-gel luminescence thin film and polyvinylbutyral (PVB) film. The luminescent spectra and lifetime of the films were measured. The final results showed that Eu(III) characteristic emission bands were observed in the spectra of all the doped films. Longer lifetimes and a higher photo-stability were observed in SiO2:Eu(III) complex luminescent thin films than in PVB:Eu(III) complex films that contained a corresponding amount of pure complexes. Heat-stability tests showed that SiO2:Eu(III) complex thin films still showed certain fluorescence after heat-treatment at a temperature of 130 degreesC, while little fluorescence could be observed in PVB:Eu(III) complex films under a UV lamp. (C) 2001 Elsevier Science B.V. All rights reserved.

Synthesis and luminescence properties of ternary europium complexes in titania matrix in the presence of dimethylformamide by a sol-gel process

In-situ synthesis of ternary europium complex with thenoyltrifluoacetone (TTA) and 1,10-phenanthroline (phen) in titania matrix in the presence of dimethylformamide (DMF) by a sol-gel process was described, which was confirmed by the luminescence excitation spectra and infrared spectra. The titania gel that contains europium complex exhibits Eu3+ characteristic emission bands and presents a longer fluorescence lifetime than the pure complexes dissolved in ethanol solution. The concentration effect on the luminescence intensity was also investigated.

Preparation and characterization of ternary europium complex-doped thin sol-gel hybrid film by fluorescence spectroscopy

Ternary europium complex with dibenzoylmethane (DBM) and 1,10-phenanthroline (phen) was in-situ synthesized in thin SiO2/polyvinyl butyral (PVB) hybrid films by a two-step sol-gel process and characterized by;means of fluorescence spectroscopy. The luminescence spectra, fluorescence lifetimes and photostability were all investigated. The results showed that the hybrid films exhibited the characteristic emission bands of the Central rare earth Eu3+. In addition, Eu3+ presented longer fluorescence lifetime than in an ethanol solution and the complex had a higher photostability in the hybrid film than in the PVB film containing the corresponding pure complex.

Metal-oxo cluster-supported transition metal complexes: hydrothermal synthesis and characterization of [{M(phen)(2)}(2)(Mo8O26)] (M = Ni or Co)

Two new metal-ore supported transition metal complexes, E{M(phen)(2)}(2)(Mo8O26) (M = Ni or CO; phen = 1,10-phenanthroline) are synthesized by a hydrothermal method and characterized by X-ray crystallography, showing that the octamolybdate possesses a novel unprecedented structure and that [M(phen)(2)](2+) units are covalently bonded to the [Mo8O26](4-) cluster.

Preparation and crystal structures of LaCl3(15-crown-5) and [LaCl2(phen)(H2O)(2)(mu-Cl)](2)center dot(15-crown-5)center dot MeCN

LaCl3(15-crown-5), I was prepared by the reaction of LaCl(3)nH(2)O with 15-crown-5 and bipy (2,2'-bipyridyl). [LaCl2(phen)(H2O)(2)(mu-Cl)](2) .(15-crown-5). MeCN, II, was crystallized from a mixture of LaC1(3) . nH(2)O, phen (1,10-phenanthroline) and 15-crown-5 in MeOH/MeCN, Crystal structures of these two complexes have been determined by X-ray methods. The La(III) ion in I is coordinated by three Cl anions and five oxygen atoms of a crown ether. The two metal ions in II are bridged by two Cl anions and the crown ligand is hydrogen-bonded to the coordinated water molecules to form polymeric... crown/cation/cation/crown... chains.

A BINUCLEAR NICKEL(II) COMPLEX CONTAINING AN OXAMIDO-BRIDGE - SYNTHESIS, PROPERTIES AND X-RAY CRYSTAL-STRUCTURE OF [NI(OXAE)NI(PHEN)(2)](CLO4)(2)CENTER-DOT-3H2O

The binuclear complex [Ni(oxae)Ni(phen)2](ClO4)(2) . H2O (oxae=N,N'bis(2-aminoethyl) oxamido dianion, phen = 1, 10-phenanthroline) was prepared from the planar monomeric complex Ni(oxae) and characterized through analytical and spectroscopic measurements. The structure of [Ni(oxae)Ni(phen)(2)] (ClO4)2 . 3H(2)O was investigated by single-crystal X-ray analysis. The complex has an extended oxamido-bridged structure and consists of two nickel(II) ions, one of them in a square planar environment and another in a distorted octahedral environment. The Ni-Ni distance is 5.267 Angstrom.