Luminescent Properties of Bi-Rare Earth Complexes with m-methylbenzoic Acid and 1,10-phenanthroline

The bi rare earth complexes EuTb( m MBA) 6(phen) 2·2H 2O, TbY( m MBA) 6(phen) 2·2H 2O were synthesized by the reaction of RECl 3 with m methylbenzoic acid and 1,10 phenanthroline in ethanol solution, where m MBA=m methylbenzoate and phen=1,10 phenanthroline. The luminescence properties of the title complexes were studied in comparison with the corresponding complexes Eu 2( m MBA) 6(phen) 2·2H 2O and Tb 2( m MBA) 6(phen) 2·2H 2O respectively. The results indicate that the emission intensity from europium ion can be greatly enhanced by the terbium ion, while the emission from terbium ion was strongly quenched by europium ion in EuTb( m MBA) 6(phen) 2·2H 2O; the emission intensity from terbium ion can be greatly enhanced by yttrium ion in TbY( m MBA) 6(phen) 2·2H 2O. The mechanism about the results was discussed.

Preparation, Characterization and Luminescent Properties of MCM-41 Type Materials Impregnated with Rare Earth Complex

Hybrid materials incorporating Eu-(TTA)3·2H20 (hereafter designated as Eu-TTA, with TTA: thenoyltrifluoroacetone) in unmodified or modified MCM-41 by 3-aminopropyl-triethoxysilane (APTES) were prepared by impregnation method. The obtained materials were characterized using X-ray diffraction (XRD), IR and diffuse reflectance spectroscopy and luminescence spectra. All the hybrid samples exhibited the characteristic emission bands of Eu3+ under UV light exci-tation at room temperature, and the excitation spectra showed significant blue-shifts compared to the pure rare-earth complex. Although the red emission intensity in the modified hybrid was almost the half of the red emission intensity in the pure Eu-TTA complex at room temperature, the hybrid showed a much higher thermal stability due to the shielding character of the MCM-41 host.

Study on Electronic Structure of Rare Earth Complex with Dioxygen

The electronic structure and chemical bonding of[Ce（CO3）3O2]28- have been studied by INDO（Intermediate Neglect of Differentiated Overlap）method in this paper.The results obtained show that theHOMO of[Ce（CO3）3O2]28- is mainly composed of the anti-bonding π orbitals of the pcroxide ion(O22-)and the LUMO is mainly composed of the 4f orbitals of the Ce（Ⅳ）.The peroxide ion coordinates to ceric ionby means of σ and π dative bonds.After coordination the O-O bond of the peroxide ions is strengthened.Bycomparison with cerous complexes,the contribution of the 4f orbitals to bonding increases in the ceric com-plex.

Studies on synthesis and fluorescent property of rare earth complexes RE(ABMF)_2AA and copolymers RE(ABMF)_2AA-co-MMA

Four new complexes RE(ABMF)2AA(RE=Sm, Eu, Tb, Dy) were synthesized by the reaction of RECl3·6H2O with acrylic acid(HAA) and 1-(2-furyl)-3-phenyl-1,3-propanedione(ABMF).The copolymerization of the rare earth complexes with methyl methacrylate was studied by using 2,2-azobis-isobutyronitrile as an initiator.The composition and structure of the four complexes were characterized by elemental analysis, UV-vis and FTIR.The glass transition temperature and molecular weight of the copolymers were determined.Photolu-minescent measurement showed that ligand ABMF could efficiently transfer the energy to Sm3+ and Eu3+ ions in the complexes and sensitize the luminescence of the rare earth ions, but could not sensitize Tb3+ and Dy3+ ions.As a result, both Sm3+ and Eu3+ complexes emitted the characteristic fluorescence of Sm3+ and Eu3+ ions due to the f-f transitions.The four copolymers could emit strong fluorescence of the rare earth ions.

Synthesis, characterization, and biological properties of nano-rare earth complexes with L-glutamic acid and imidazole

四个 nano 稀罕的地球 L-glutamic 酸和咪唑 RE (Glu ) 的第三的建筑群 3ImCl3 慎 ???? 湩吠 ? 瀠潲楶敤 ? 桴 ? 敤楳敲 ? 牰摯 ' 撰 B?????????? ?? 嚰 ? 颹? è蹠 ? 蹠？？

Synthesis, Characterization and Vulcanizing Properties of Rare Earth Complexes with 2-Mercaptobenthiazole

Eight complexes of rare earth with 2 mercaptobenthiazole, RELCl 2·RE(OH) 3· x H 2O (L=2 mercaptobenthiazole, RE= La～Gd, Y, except for Pm, x =0, 2～4), were synthesized in unhydrous ethanol and characterized by elemental analyses, IR spectra and thermal analyses. The results show that the ligand is coordinated to the RE ion through both the exocyclic sulfur and the thiazole nitrogen. The vulcanizing properties of the La complex as accelerator were studied in the traditional tire rubber, which indicate that the cross linked rubber accelerated by the rare earth complex has good physical and dynamic mechanical properties by comparison.

Synthesis and Crystal Structure of Rare Earth Complex withCiprofloxacin

The complex of rare earth with ciprofloxacin has been synthesized and characterized bymeans of x-ray single crystal diftraction. The structure features of the complex are decribed.

Study on Luminescence Properties of a Novel Rare Earth Complex Eu(TTA)_2(N-HPA)Phen

A novel rare earth complex Eu(TTA)2(N-HPA)Phen (TTA=thenoyltrifluoroacetone, N-HPA=N-phenylanthranilic acid, and phen=1,10-phenathroline), which contains three different ligands, was synthesized. The Eu complex was blended with poly N-vinylcarbazole (PVK) in different weight ratios and spin coated into films. The luminescence properties of films were investigated and energy transfer between PVK and the complex was discussed. Multilayer structural devices consisting of ITO/PVK∶Eu(TTA)2(N-HPA)phen/BCP/Alq3/A1 were fabricated with PVK∶Eu(TTA)2(N-HPA) as light-emitting layer. Increasing the concentration of Eu in the PVK thin film would inhibit the emission of PVK to different degrees. Finally, the pure red luminescence of europium(Ⅲ) was observed when the doping weight ratio was approximately 1∶5, which indicated an effective energy transfer from PVK to rare earth complex.

Interaction between Ternary Rare Earth Complexes of Cinnamic Acid and Phenanthroline with DNA by Spectroscopy

The interaction of ternary complexes [RE（phen）（cin）3（H2O）]（RE= Nd （III）,Ce（III）,Eu（III））with calf thymus DNA was investigated by electronic absorption spectroscopy, ethidium bromide（EB）-DNA quenching fluorescent spectra and resonance light scattering. All experimental results indicate that the three complexes bind to DNA by the electrostatic mode and the intercalative mode. It is predicted that these complexes show high anticancer activity or other biologic activity.

Synthesis and Photoluminescence Properties of Rare Earth Complexes with 3-Allyl-2, 4-Pentanedione

In order to combine the merits of rare earth organic complexes with excellent material performances of polymers,a polymerizable chelating agent,3-allyl-2,4-pentane dione(APD),was synthesized by phase transfer catalysis and its rare earth complexes were prepared.The compounds were characterized by EA,IR and 1H NMR.Their UV spectra and fluorescence spectra were investigated.The effects of allyl on the luminescence properties of the complexes were studied.The results show that the sensitization of APD is changed by allyl in comparison with that of acetyl acetone(acac),and it becomes an ideal novel ligand of Eu.In addition,intramolecular energy transfer mechanism in the luminescence process in the complexes was also discussed in detail.

An Encapsulation of the Rare Earth Complex in Modified Mesoporous Molecular Sieve MCM-41

The encapsulation of a rare earth （RE） complex Eu（DBM）3phen in modified Si- MCM41 with 3 -aminopropyltriethoxy st.lane is reported for the first time. The luminescence intensity of the RE complex in the modified Si-MCM-41 is about 9 times as strong as in unmodified Si- MCM41 and the luminescence of the RE complex in the modified Si-MCM-41 has good color purity.

Preparation and Properties of Rare Earth Complexes with 5-Phenyl Pyrazoline Dithioformate

Nine complexes of rare earths with 5 phenyl pyrazoline dithioformate, Na[RE(S 2CNC 9H 9 N) 4· x H 2O (RE=La～Dy, Y, except for Ce and Pm) were synthesized in dry N 2 atmosphere and characterized by elemental analyses, molar conductance, IR spectra, thermal analyses. The results show that the ligands coordinate to the RE ion through two sulphur atom donors. Thermal analyses indicate that the thermal stability of the complex is not higher than that of sodium 5 phenyl pyrazoline dithioformate. The complexes are easily soluble in acetonitrile and tetrahydrofuran. The molar conductance values of the complexes measured in acetonitrile (1 24～1 32×10 -3 mol·dm -3 ) at 25 ℃ are in the range of 86～104 Ω -1 ·cm 2·mol -1 , indicating that they are 1∶1 electrolytes.

Synthesis,Characterization,and Luminescence Properties of a Multi-benzoic Acid Rare Earth Complex Applied to Fluorescence Nanometer and Micrometer Fiber

The design and synthesis of a novel multi-benzoic acid ligand and the luminescence properties of the rare earth complex with the ligand and Eu3 +were focused on. The composition and structure of ligand and complex were characterized by Fourier transform infrared( FT-IR) spectroscopy,1H nuclear magnetic resonance(1H NMR) techniques, and element analysis. The luminescent properties,heat resistant performance,morphology and distribution in fibers of the complex were also measured. The fluorescent spectra indicate that as-synthesized complex owns excellent luminescent properties. The maximum relative fluorescence intensity of the complex is more than 7 000. The thermo-gravimetric analysis( TGA) results confirm that the initial degradation temperature of as-synthesized complex is at 413 ℃. Transmission electron microscope( TEM) and field-emission scanning electron microscope( FESEM) photos show that the particle size of assynthesized complex is 50-60 nm,and can be uniformly distributed in fiber. Based on these results, it can be concluded that the synthesized complex has excellent luminescent properties, good thermal stability,and extensively application prospect.

Synthesis, Characterization and Antibacterial Properties of Rare Earth Complexes with L-Phenylalanine and o-Phenanthroline

New solid ternary complexes of rare earth with L-Phenylalanine （L-Phe） and o-Phenanthroline （Phen） were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar conductance, IR, Raman, UV-VIS, TG-DTA. The compositions of the complexes were confirmed to be RE（Phe）3Phen Cl3·3H2O（RE=La 3+, Ce 3+, Pr 3+, Nd 3+, Sm 3+, Eu 3+, Er 3+, Y 3+）. The antibacterial activities testing indicates that all these solid ternary complexes have antibacterial ability against Escherich coli, Staphy lococcus aureus, Candida albican （MIC are about 65×10 -4%, 15×10 -3%, 4×10 -2%, respectively）.

Synthesis, characterization, and anticancer properties of rare earth complexes with Schiff base and o-phenanthroline

Five novel ternary complexes of the rare earth ions with o-phenanthroline(Phen) and Schiff base salicylaldehyde L-phenyla- lanine(KHL) were synthesized in ethanol. Their compositions were characterized by elemental analysis, molar conductance, 1H NMR, FT-IR, and Raman spectra. The formulas of the complexes were verified to be RE(L)(Phen)Cl(H2O) (RE=La3+, Ce3+, Nd3+, Er3+, and Gd3+; L=Schiff base salicylaldehyde L-phenylalanine; phen=o-phenanthroline). Methyl thiazolyl tetrazolium (MTT) colorimetry and flow cytometry were used to test the anticancer effect of the complexes with K562 tumor cell. The research showed that the complexes could inhibit K562 tumor cell′s growth, generation, and induce apoptosis. The inhibition ratio was accelerated by increasing the dosage, and it had significant positive correlation with the medication dosage.

Study on Adsorption Behavior of Rare Earth Complexes on Nanometer-Size Titanium Dioxide with ICP-AES

A new method of using nanometer TiO 2 as solid phase extractant coupled with ICP AES was proposed for speciation of rare earth elements. The adsorption behavior of rare earth complexes on nanometer TiO 2 was investigated. Effect of pH value, contact time, elution solution and interfering ions on the recovery of the rare earth complexes were studied. A quantitative recovery (>90%) was found in the pH range of 4～9.0 for Eu citric, 4.5～9.0 for Eu oxine and Eu HIBA, and 6.5～9.0 for Eu 3+ . Eu EDTA can not be adsorbed in the pH range studied. There is large difference in the adsorption behavior on nanometer TiO 2 between rare earth element and its complexes. The possibility of application of nanometer TiO 2 on the speciation of rare earth element was explored.

Preparation and Characterization of Layered Compound Zirconium Bis(monohydrogenphosphate) Intercalated with Rare Earth Complex

Layered compound zirconium his（monohydrogenphosphate）（α-ZrP） intercalated with rare earth complex Eu（DBM）3phen was prepared. The pre-intercalation of p-methoxyaniline into α-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.

The Thermodynamic Property of Rare Earth Complexes with L-Threonine

In this paper the stability constants and thermodynamic parameters for complexes of rare earth elementswith L-threonine have been measured systematically by potentiometry and calorimetry at 25℃ and ionicstrength of 0.15 mol/L(NaCl).The thermodynamic values for protonation of the anion of L-threonine havebeen obtained.The dependence of stability,enthalpy and entropy change of the complex upon atomic number ofcation is investigated,and the coordination of L-threonine to rare earth is also discussed in detail.

Syntheses and Infrared Spectra of Rare Earth Complexes with Diethyl Phosphate

The title complexes Ln（DEP）,（Ln=La,Sm,Eu,Ho and Yb）were synthesized by reaction of triethylphosphate with trivalent rare earth chlorides.The mechanism of thermo-decomposition of the complexes hasbeen studied.According to their IR spectra,the residues of the thermo-decomposition of the complexes wereidentified as Ln（PO3）3.Their IR spectra were measured and principal IR bands were assigned.The experimentalresults of the IR spectra of the complexes show that the title complexes have the same coordination form and mo-lecular configuration as rare earth,e.g.Sm,complex with dimethyl phosphate（Sm（DMP）3）.Each of the rareearth ion links three rare earth ions nearby through double“O-P-O”bridges to form a special network ofrings-linking-rings,each of which consists of twenty-four atoms.The Ln-O bond is principally ionic.

Synthesis, Catalysis of Rare Earth Complexes with Aliphatic Noncyclic Polyether-Amino Acid Schiff Base

Eleven new rare earth complexes with aliphatic Schiff base, condensed from diglycol aldehyde and bis-arginine, were synthesized and characterized. They are confirmed as Ln（H2DAAR）（NO3）3·7H2O （Ln=La, Pr, Nd, Gd）, Ln3（H2DAAR）2（NO3）9·5H2O （Ln=Dy, Y） and Ln2（H2DAAR）（NO3）6·3H2O （Ln=La, Nd, Sm, Gd）, Ln3（DAAR）（NO3）7·4H2O （Ln=Dy, Yb, Y） respectively under different molar ratios of metal to ligand （DAAR=diglycol aldehyde bis-arginine）. The present paper deals with a synthetic method and catalytic properties of obtained complexes. The result shows that proper pH value is important for synthesis of the complexes and compositions of the lighter and the heavier rare earth complexes are different under the same reaction condition. Some new complexes obtained have proved their catalytic activity and 80% conversion with the viscosity-average molecular weight 230,000 for the polymerization of methyl methacrylate （MMA） without addition of any cocatalyst.