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=La^3＋, Ce^3＋, Nd^3＋, Er^3＋, and Gd^3＋; 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.     

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(PO_3)_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.     

Fabrication and Luminescence of Rare Earth Complex／SiO2 Hybrid Nanospheres

The organic rare earth complex was embedded in silica spheres to form inorganic-organic hybrid. Photoactiver are earth complexes with various organic ligands exhibit intense narrow emission band, and the silica is an excellent matrix for inorganic-organic structure. The transmission electron microscope image presents the hybrid nanospheres. The diameter of the hybrid is about 100 nm. The europium complex that incorporated into silica sphere is also proved by the IR spectra, the excitation and emission spectra. The lifetimes of the Eu3 ions in the hybrid nanospheres and in the pure europium complex were also detected. This hybrid with inhomogeneous compositions exhibits specifically tailored chemical and optical properties, such as perfect thermal and mechanical stability, colorimetric purity and so on. It can be used as luminescent and optical material in EL and PL fields.     

Theoretical elucidation of rare earth extraction and separation by diglycolamides from crystal structures and DFT simulations

Diglycolamides(DGAs) show excellent application prospects for the extraction and separation of rare earth metals from highly radioactive liquid wastes and rare earth ores.The extraction ability of DGAs for rare earth ions in nitrate or chloride media increases with increasing atomic number of the rare earth metal.To understand the origin of this phenomenon,three binuclear crystals [Ln(TEDGA)3][Ln(NO_3)_6] of N,N,N',N'-tetraethyldiglycolamide(TEDGA) with rare earth ions La(Ⅲ),Pr(Ⅲ) and Eu(III) were prepared and characterized crystallographically.The three complexes belong to the triclinic crystal system,P-1 space group.The bond lengths of Ln-O_(amide) are significantly shorter than those of Ln-O_(ether) in the same crystal.The Ln-O_(amide) and Ln-O_(enher) bond lengths gradually decrease with increasing atomic number of the rare earth ion.The dihedral angle formed by TEDGA and metal ions through the tridentate coordination gradually increases with increasing metal ion atomic number,tending toward the formation of sizeable planar coordination structures for the most massive rare earth ions.The structures of the compounds formed by the extractant and metal ion were optimized by means of DFT simulations.We find that the interaction between TEDGA and the rare earth ion is dominated by electrostatic interaction by analyzing binding energy,WBIs,Mulliken charge,natural electron configurations,and molecular orbital interaction.The covalent component of the Ln-O bonds of the complexes increases with increasing metal atomic number.The observed increase in extraction and separation capacity of diglycolamides for rare earth ions with increasing atomic number might be due to the formation of two fivemember rings by one tridentate ligand.The rare earth ions with large atomic numbers tend to form planar structures with large dihedral angles with DGA ligands.     

Energy Transfer from PVK to Europium Complex in Electroluminescence

The spectra of solutions, films and light-emitting diodes of rare earth complexes were studied. It is shown that the absorption spectra of PVK-dopping rare earth complexes can be red-shifted to the visible region and overlap with the emission spectrum of PVK, which makes the energy transfer possible from PVK to the rare earth ion.     

Synthesis and Characteristic Study on Complexes of Europium（Ⅲ） and Maleic Acid Doped with Non-Fluorescent Ions

Complex of europium （Ⅲ） with maleic acid, and binuclear complexes of europium（Ⅲ）with maleic acid doped with non-fluorescent ions gadolinium, lanthanum and yttrium, were synthesized. The compositions and structures of complexes were characterized with elemental analysis, single crystal X-ray diffraction, IR and DSC-TG. Fluorescent properties were studied with fluorescence spectrum. The results indicated that the strongest fluorescent complexes were obtained when the ratio of europium and non-fluorescent ion was 8：2. The order of Eu^3＋ fluorescence strengthened by three doped rare earths was Gd^3＋ 〉La^3＋ 〉Y^3＋     

Effect of Cycling Loaded Rare Earths on Stripping Process in P507 Extraction System

P507 （HEH [EHP]） is an important extractant for the separation of rare earth and is widely used in industry. Since the complexes of heavy rare earth ions with saponified P507 are so stable that the rare earth ions are difficult to be exchanged and stripped by H^＋ ions. Thus, the cycled extractant loads certain amount of heavy rare earth ion after stripped by acid. This amount of rare earth ions loaded in blank organic phase is named as the ＂cycling loaded rare earth ions （CLREs）＂. In the separation process of Tm^3＋, Yb^3 ＋, and Lu^3 ＋ , the amount of CLREs carl be more than 10% of the normal capacity of saponifiedorganic phase. In fact, CLREs affect the separation efficiency and decrease the purity of the products. Based on the extracting-stripping equilibrium and mass balance, the influence of different process parameters on the amount of CLREs was studied by computer simulation. The results indicate that higher acid consumption and more stripping stages are required to eliminate CLREs. For an industrial practice, however, the acid consumption and the number of stripping stage can be designed by choosing an economic process and controlling CLREs at a reasonable level.     

Synthesis and spectroscopic properties of rare earth picrate complexes with a new dinaphthalenelamide

The new ligand N-benzyl-2-{2’-[(benzyl-ethyl-carbamoyl)-methoxy]-dinaphthalene-2-yloxy}-N-ethyl-acetamide(L) and its complexes of rare earth picrates were synthesized.The complexes were characterized by elemental analysis,IR,UV-vis spectra and conductivity measurements.The fluorescence properties of the europium complex in solid state and CHCl3,ethyl acetone,acetonitrile and DMF were investigated.Under the excitation,the europium complex exhibited characteristic emissions of europium.The lowest triplet state energy level of the ligand indicated that the triplet state energy level of the ligand matched better to the resonance level of Eu(Ⅲ) than Tb(Ⅲ) ion.     

CHARACTERISTIC CURVES OF M-H AND COEXISTENCE OF MAGNETISM WITH SUPERCONDUCTIVITY FOR HIGH T_c SUPERCONDUCTORS REBa_2Cu_3OT_(7-x)

Some high T_c superconductors REBa_2Cu_3O_(7-x)(RE=Sm,Eu,Gd,Dy,Ho,Er,Tm) with zero resist-ance temperatures were about 90K have been prepared.The effect of magnetic rare earth ions on the transi-tion temperatures is not very great,but their magnetic behaviours are different from each other.Themagnetization loops of these compounds have been measured at 77K.The coexistence of superconductivitywith magnetic ordering (COSM) found in the samples with RE=Gd,Dy,Ho,Er,Tm,indicates that thereare two possible ways of coexistence in the samples.These expertments show that the relation ofparamagnetism to the atomtc number of rare earth elements for these superconductors is similar to that ofrare earth ions in some paramagnetic salt crystals,which indicates that the magnetism of the samples origi-nates from the local magnetic moments of rare earth ions.In some samples there is antiferromagnetie orderingat low temperatures,and the effective Bohr magneton numbers are consistent with that of free rare earth ions.Some superconducting parameters including the critical current density are calculated according toGinzburg-Landau theory and the critical state model.     

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.     

Synthesis, Characterization and Fluorescence Properties of Europium, Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline

Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen)L3·1/2H2O; Tb(phen)L3·H2O and Tb0.5RE0.5(Phen)L3·1/2H2O. (RE=Y3 , La3 and Gd3 ; L=biphenyl 4-carboxylic acid; phen=o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE(Ⅲ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3 is raised by inert fluorescent rare earth ions (Y3 , Gd3 and La3 ), but in Tb3 hetero-nuclear rare earth complexes the intensity of Tb3 ions are quenched by the inert fluorescent rare earth ions.     

苯甲酰胺-桂皮酸-铕-镧配合物的红外光谱及荧光光谱研究

用氯化铕和氯化镧混合溶液与苯甲酰胺及桂皮酸铵在水溶液中反应 ,合成了苯甲酰胺 -桂皮酸 -铕-镧配合物 ,其化学组成式为 ( Eux L a1- x) L′L3(其中 L′代表 C6 H5CONH2 ,L 代表 C6 H5CH=CHCOO- ,x分别为1 .0 0 ,0 .90 ,0 .70 ,0 .50 ,0 .30和 0 .1 0 )。测定了配合物的红外光谱及荧光光谱。结果表明 ,苯甲酰胺的氧原子和氮原子均与稀土离子配位 ;桂皮酸的羧基氧与稀土离子成键。在系列配合物中 ,由不发光的 La3 离子取代部分发光的Eu3 离子 ,可明显提高 Eu3 离子的特征荧光。本文对发光机理进行了初步探讨。     

稀土铕,铽β-二酮配合物的合成与发光性能

采用Claisen缩合反应合成了一种新型的β-二酮化合物1-(4-溴苯)-3-苯基丙烷-1,3-二酮(L),并以其为第一配体,邻菲罗啉(phen)为第二配体,合成出新型稀土铕,铽二元及三元配合物。通过元素分析、红外光谱、紫外光谱、荧光光谱对合成的配体及配合物进行了表征。元素分析确定了配合物的组成。红外光谱的分析表明第一配体L中的氧原子以及第二配体phen中的氮原子与稀土离子进行了配位。紫外光谱表明第一配体L为能量的给体,第二配体phen起协同作用。通过荧光光谱研究了配合物的发光性质,结果显示三元配合物的发光强度大于二元配合物,三元配合物Eu(L)3phen表现出Eu3+的特征发射,在593,615,653,701 nm处的发射峰分别归属于Eu3+的5D0→7Fj(j=1,2,3,4)能级间的跃迁,并且以位于615 nm处的5D0→7F2电子跃迁所发出的荧光强度最大;而铽配合物中并没有出现Tb3+的特征发射。进一步的研究表明,这是由于配体L的最低三重态能级较适合Eu3+的发射能级,配体L吸收的能量可以有效的通过Antenna效应传递给稀土中心离子,使得三元配合物Eu(L)3phen的发光强度较大。     

邻氨基苯甲酸-联吡啶-混合稀土(Eu、Tb)配合物的荧光研究

:研究用邻氨基苯甲酸铵、2 ,2’-联吡啶与氯化铕、氯化铽在水 -乙醇溶液中反应合成了邻氨基苯甲酸- 2 ,2’-联吡啶 -铕铽异核稀土配合物 ,并测定了配合物的红外光谱。红外光谱数据表明 :邻氨基苯甲酸中的羧基和氨基均与稀土离子配位 ,联吡啶中的氮也与稀土离子配位 ;由元素分析数据推测 ,配合物的化学组成式为(Eux Tb1 - x) L3L′(其中 L 为邻氨基苯甲酸 ,L′为 2 ,2’-联吡啶 ) ;在 35 1nm紫外光激发下 ,研究了配合物的荧光光谱 ,结果表明 ,Eu3 的荧光发射被 Tb3 强烈敏化 ,而 Tb3 的荧光发射被 Eu3 离子强烈猝灭     

Photophysical Properties of Rare Earth Complexes with 3,4 Furandicarboxylic Acid and 1,10 Phenanthroline

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Synthesis and fluorescence properties of Eu（Ⅲ）, Tb（Ⅲ） and Sm（Ⅲ） with β-diketone and 2,2＇- bipyridine

Three new rare earth ternary complexes,RE(PPP)3bpy(RE=Sm 3+ ,Eu 3+ ,Tb 3+ ),were synthesized by the reaction of 1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP)and 2,2′-bipyridine(bpy)with rare earth chloride RECl3,respectively,in alcohol solution. The compositions were characterized by means of infrared(IR)spectra,chemical analysis,elemental analysis,and thermodynamic analysis.Luminescent properties of the three complexes were studied.At room temperature,under UV light excitation,the Sm 3+ ,Eu 3+ and Tb 3+ complexes exhibited characteristic emission of the central ions.The fluorescence spectra showed that the fluorescence emission intensity of Eu 3+ complex was the strongest.The narrow strongest emission band of Eu 3+ complex was considered to be a valuable material with bright red fluorescence.     

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. Photoluminescent 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.     

Study on Copolymer of PMMA with Eu Complex

The europium complex, Eu3 -1,10-phenanthroline (Phen) -acrylic acid (AA) was prepared and its structural formula is Eu(Phen) (AA)3. The high luminescence rare earth polymer materials were obtained by the copolymerization of europium complex with methyl methacrylate using AIBN as an initiator. The copolymer structure and properties were characterized by FT-IR, UV-Vis, RF spectra and thermogravimetric analysis (TG). Results indicate that block copolymer is synthesized. Fluorescent property shows that Eu copolymer emits rare earth fluorescence and the emission intensity increases with the rise in Eu content and reaches a maximum value.     

稀土硝酸盐与希夫碱邻香兰素缩丙氨酸盐及邻菲咯啉三元配合物的合成与表征

合成了稀土硝酸盐与希夫碱邻香兰素缩丙氨酸盐(以KHL表示)及邻菲咯啉的三种固体三元配合物。通过元素分析、差热-热重、红外光谱、紫外光谱及摩尔电导分析等手段,确定配合物的组成为［RE(L)(Phen)(H2O)］NO3,(RE=Y,Nd,Sm)。并对它们的配位方式及某些性质进行了研究。     

Synthesis of novel europium complexes and their photoluminescence properties

Two novel luminescent Eu(III) complexes with the formulas(NIP)Eu(DBM)3 1 and(ENIP)Eu(DBM)3 2(NIP=2-(naphtha-len-1-yl)-1H-imidazo [4,5-f] [1,10] phenanthroline,ENIP=1-ethyl-2-(naphthalen-1-yl)-1H-imidazo [4,5-f] [1,10] phenanthroline,DBM= dibenzoylmethanato) were successfully synthesized and characterized by IR and elemental analysis.The UV-vis absorption spectra and pho-toluminescence properties of the complexes were investigated,and the irradiation at the absorption band between 300-400 nm of europium complexes either in solution or in the solid state led to the emission of a sharp red band at ~610 nm,a characteristic Eu3+ emission due to the transition of 5D0→7F2.Furthermore,the weak emission bands around 587 and 595 nm attributed to 5D0→7F0 and 5D0→7F1 transition were also displayed in the emission spectra.These results demonstrated that the Eu(III) ion was sensitized efficiently by the ligand and displayed photoluminescence with high intensity,narrow half-peak width,and monochromic light.The excited-state lifetimes of 1 and 2 were in the microsecond time scale,but the photoluminescence quantum yield of 2(0.03) was two times higher than that of 1(0.01) which should be at-tributed to the effect of the ethyl substituting in ENIP.