Synthesis and photoluminescence properties of Eu(pzc)3(phen) and Eu(mpzc)3(phen)

Novel europium(III) complexes, (2-pyrazinecarboxylato)(phenanthroline) europium(III) [Eu(pzc)₃(phen)] and (5-methyl-2-pyrazinecarboxylato) (phenanthroline)europium(III) [Eu(mpzc)₃(phen)] have been designed and synthesized. These complexes were characterized by FT-IR, UV-Vis, and X-ray photoelectron spectroscopy. Photoluminescence (PL) studies showed that the two complexes emitted remarkably red luminescence. When powder samples of Eu(pzc)₃(phen) and Eu(mpzc)₃(phen) were examined using time-resolved spectroscopic analysis, the luminescence lifetimes were found to be 1.05 and 2.36 ms, respectively. Thermogravimetric analysis showed that the europium complexes possessed good thermal stability up to 345–350 °C.     

Synthesis and spectroscopic characterization of fluorescent solid rareearth complexes with hydroxamic acids

The complexes RE2(DHYA)3.nH2O in the title bar were synthesized through some reactions of trivalent rareearth ions.In the process of synthesis,dihydroxam,ic acids were taken as ligands while the alcohol was taken as a solvent.The ligands included adipylhydroxamic acid(ADHA),p-phthalichydroxamic acid(PPHA),oxalohydroxamic acid (OXHA),butadihydroxamic acid(BDHA),o-phthalichydroxamic acid(OPHA),benzoylhydroxamic acid(BHA),etc.Measured at 25℃,the molar conductances in various modes are 13.00-21.05 S.cm^2.mol^-1,which shows that rare-earth complexes are nonelectrolytes and the hydroxamino groups of the complexes have taken part in bonding.Infrared spectra,ultraviolet spectra,nuclear magnetic resonance(1HNMR) spectra,and fluorescence spectra were used to investigate the complexes,Experiments have proved that the complexes of Eu^3 and Tb^3 with aromatic hydroxamic acids have good fluorescent characteristics.     

Complexation, luminescence and energy transfer of Ln(III) ions with phenylphosphonic acid

Spectral characterisation of the Ln(III) ion complexes with phenylphosphonic acid (PPA) was made and the mode of Ln(III) ions coordination was established. From the absorption spectra the forces of the Nd³⁺ oscillator were obtained, the intensity of emission and luminescence lifetimes of Eu³⁺ and Tb³⁺ were measured. The Stern–Volmer constants K_sv^φ and K_sv^τ determined indicated the presence of associated forms of complexes. The quantum yield of luminescence of Eu³⁺ and Tb³⁺ complexes was found using Ru(bpy)₃²⁺as a standard. The complexes were characterised by quantum yields (Φ=0.4 and 0.008 for Tb and Eu ions). The solid state Eu³⁺ complex was studied by luminescence spectroscopy, IR and thermogravimetry. The complex was found thermally stable and with no water molecules in its structure.     

Synthesis and photoluminescence of Eu（DBM）3phen/APTES-SBA- 15 with morphology of pearl-like chains

Novel ordered mesoporous Eu（DBM）3phergAPTES-SBA-15 （EAS） composites with reasonable photoluminescence property and interesting morphology of bundles of pearl-like chains were synthesized. The characteristics of the mesostructure and the optical properties of the prepared samples were investigated by means of XRD, FTIR, SEM, TEM, N2 adsorption-desorption and PL spectroscopy. The results indicate that the as-made EAS composites have long-distance ordered mesoporous structure. Compared with the Eu（DBM）3phen complex, it is found that the EAS composites perform a considerable photoluminescence with good color purity. It is proposed that the anchored amin~ from the APTES and quantum size effect of the Eu（DBM）3phen complex have great effect on the photoluminescence of the EAS composites.     

Voltammetry and fluorescence studies on the interaction between Eu(phen)_3~(+3)and DNA

The binding mode of Eu(phen) 3+3 with DNA is studied by fluorescence and voltammetric methods. From the Scatchard graph and the fluorescence quenching phenomenon, it is concluded that the mode of interaction between Eu(phen)3+3 and DNA is intercalation bind by inserting the phen ?-? conjugate surface between the base pairs of the DNA duplex. Voltammetry was used to confirm the results obtained from the fluorescence method, the result from both methods agrees with each other. The binding constant (K) and the binding site size (ns) were calculated from voltammetric data such as the shifts in potential and limiting currents in the process of adding DNA, according to the positive shifts of peak potential. It was considered that the complex of the +2 ion interacted more favorably with the nucleotide bases than that of the +3 ion by hydrophobic interaction.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Tb(Ⅲ),β-diketones and 1,10-phenanthroline (phen)

In order to study the luminescent properties of ternary rare earth complexes with fl-diketone ligand,three new β-diketone ligands,1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP), 1-(2-thienyl)-3-(p-phenylethynylphenyl)-l,3-propanedione (HTPP) and 1-(2-furyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HFPP),were synthesized by Sonogashira coupling reaction and Claisen condensation.Three new ternary rare earth complexes,TbL3phen (L = PPP,TPP,or FPP),were synthesized by the reaction of rare earth chloride TbCl3,1,10-phenanthroline (phen) with HPPP,HTPP,or HFPP respectively,in alcohol solution.The compositions were characterized by means of elernental analysis,chemical analysis,and IR spectra.Luminescent properties of the three new complexes have been studied.The results show that the ternary Tb(Ⅲ) complexes only emit the weak fluorescence of the Tb(Ⅲ) ion,which reveals the triplet state energy of the ligands does not match well with the excited state vibrating energy of Tb3+ ion.     

Syntheses and cofluorescence of complexes of Eu（Ⅲ）/Y（Ⅲ） with terephthalic acid, 2-thenoyltrifluoroacetone and trioctylphosphine oxide

A series of Eu（ Ⅲ）/Y（Ⅲ） complexes of terephthalic acid（TPA） with 2-thenoyltrifluoroacetone（HTTA） and trioctylphosphine oxide（TPPO） were synthesized. Compositions of these complexes are revealed to be Eu2（1-x）Y2x（TPA）（TTA）4- （TPPO）4 or EU1-xYx（TPA）（TTA）（TPPO）2. Their 1R spectra, fluorescent spectra and the thermal and optical stability were studied. The fluorescent excitation spectra of these complexes show more broad excitation bands than those of Eu2（TPA）3（TPPO）4 and Eu（TTA）3（TPPO）2 corresponding to their formations. In addition, both the binuclear complex EuY（TPA）（TTA）4（TPPO）4 and the chain complex EU0.4Y0.6（TPA）（TTA）（TPPO）2 present higher thermal stability and better optical stability than the mononuclear complex Eu（TTA）3（TPPO）2 does. And their thermal and optical stabilities are preferably interpreted from the binuclear structure together with the chain polynuclear structure of the complexes. The fluorescence enhancement of cofluorescence Y^3＋ ions to the Eu（Ⅲ） complexes is clear. The optimum content of Y^3＋ is 0.6 （molar fraction） for the chain complexes Eu1-xYx（TPA）（TTA）- （TPPO）2 and 0.5 for the binuclear complexes Eu^2（1-x）Y2x（TPA）（TTA）4（TPPO）4. The formation of polynuclear structure of the complex Eu1-xYx（TPA）（TTA）（TPPO）2 appears to be responsible for the good cofluorescence effect of Y^3＋ ions.     

Preparation and fluorescent properties of europium (III) complexes with β-diketone ligand and 2,2-dipyridine or 1,10-phenanthroline

The β-diketone ligand, 1-(4-methoxyphenyl)-3-phenylpropane-1,3-dione (MPPD), and its binary Eu(III) complexes Eu(MPPD)₃, ternary complexes Eu(MPPD)₃·Bipy with 2,2-dipyridine (Bipy) and Eu(MPPD)₃·Phen with 1,10-phenanthroline (Phen) were prepared. The complexes were characterized with by elemental analysis, FT-IR, ¹H NMR, UV–vis absorption, thermogravimetric analysis (TGA), ESI-MS and fluorescence spectroscopic techniques. TGA results showed that these complexes have good thermal stability. The emission spectra for complexes 2–4 exhibited the characteristic emission bands that arise from the ⁵D₀ → ⁷F_J (J = 0–4) transitions of the europium ion in solid state and chloroform solution. Based on the emission spectra in solid state, the Eu(III) ion could be sensitized efficiently by the ligands to some extent, in particular, in the ternary system, the secondary ligands Bipy and Phen acting as a light-harvesting center was involved in the highly efficient energy transfer process. In addition, the experimental intensity parameters, Ω₂ and Ω₄ were calculated from the fluorescence emission spectra. The radiative decay rate A_rad, the nonradiative rates A_nrad, the lifetime (τ) and the luminescent quantum yield (η) were determined and analyzed.     

An efficient luminescent bonding-type Eu-containing copolymer as a red-emitting phosphor for fabrication of LED

A luminescent europium-containing copolymer, poly(MMA-MA-co-Eu(TTA)₂phen), was synthesized though a reaction of EuCl₃, 1,10-phenanthroline (phen), α-thenoyltrifluoroacetone (TTA) with copolymer of maleic acid (MA) and methyl methacrylate (MMA). The copolymer was characterized by FT-IR, UV–vis, gel permeation chromatograph (GPC), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. The Eu-copolymer phosphor exhibited high thermal stability and excellent photoluminescence properties, appropriate CIE chromaticity coordinates for red and a quantum yield of 24% under near-UV light excitation. It emitted intense red light at 613 nm under UV excitation at room temperature, which is attributed to the ⁵D₀ → ⁷F₂ transition of Eu(III) ions. An intense red-emitting light-emitting diode (LED) was fabricated by combining poly(MA-MMA-co-Eu(TTA)₂phen) with a 395 nm-emitting InGaN chip. The results indicate that the Eu-copolymer phosphor may act as a red component for fabrication of white LEDs.     

Fluorescence of complexes of EuⅢwith aromatic carboxylic acid-1,10-phenanthroline

Fluorescence of complexes of EuⅢwith aromatic carboxylic acid-1,10-phenanthroline@舒万艮 @周忠诚 @牛聪伟~~     

Synthesis,luminescent properties,and theoretical study of novel Sm~(3+) and Dy~(3+) complexes containing β-diketone and 1,10-phenanthroline

Two new ternary complexes of 1-(2-thienyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HTPP) and 1,10-phenanthroline (phen) with Sm³⁺ and Dy³⁺ were synthesized. The composition of the ternary complexes was characterized as Sm(TPP)₃phen and Dy(TPP)₃phen, respectively, by infrared (IR) spectra, chemical analysis, elemental analysis, and thermodynamic analysis. At room temperature, under UV light excitation, the Sm³⁺ and Dy³⁺ complexes exhibit characteristic emissions of the central ions. It is found that the fluorescence intensity of Sm(TPP)₃phen is stronger than that of Dy(TPP)₃phen. In order to explain this phenomenon, an accurate quantum chemistry calculation was carried out, and the result is in good agreement with the experiment data.     

Synthesis and emission analysis of novel rare earth complex Eu（TTA）3（2NH2-Phen）

The rare earth ternary complex of Eu 3+ with thenoyltrifluoroacetone,and 4,7-2NH2 phenanthroline was synthesized and well characterized by UV,fluorescent,IR spectrometry and X-ray diffractometry(XRD)as well as elemental analysis.The results show that the complex of Eu(III)emits strong red luminescence when excited by UV light,and Eu(TTA)3(2NH2-Phen)has the higher sensitized luminescent efficiency and longer lifetime than Eu(TTA)3(Phen).In device of ITO/PVK/Eu(TTA)3(2NH2-Phen)/Al,the spectra of Eu(TTA)3(2NH2-Phen)with different ratios for spin-cast film were monitored.The main emitting peak at 614 nm can be attributed to the transition of 5 D0→ 7 F2 of Eu 3+ and this process results in the enhancement of red emission from electroluminescence device.The effect and mechanism of the ligands on the luminescence properties of europium complex were discussed.The results show that the luminescence intensity of the title complexes greatly increases in comparison with that of their corresponding complexes,revealing that the second ligands form very good synergistic effect with the first ligands.The title complexes possess excellent thermal stability properties,and are hopefully developed into fine PL and EL red materials.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Tb(III), β-diketones and 1,10-phenanthroline (phen)

In order to study the luminescent properties of ternary rare earth complexes with β-diketone ligand, three new β-diketone ligands, 1-phenyl-3-(p-phenylethynylphenyl)-1,3-propanedione(HPPP), 1-(2-thienyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HTPP) and 1-(2-furyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HFPP), were synthesized by Sonogashira coupling reaction and Claisen condensation. Three new ternary rare earth complexes, TbL₃phen (L = PPP, TPP, or FPP), were synthesized by the reaction of rare earth chloride TbCl₃,1,10-phenanthroline (phen) with HPPP, HTPP, or HFPP respectively, in alcohol solution. The compositions were characterized by means of elemental analysis, chemical analysis, and IR spectra. Luminescent properties of the three new complexes have been studied. The results show that the ternary Tb(III) complexes only emit the weak fluorescence of the Tb(III) ion, which reveals the triplet state energy of the ligands does not match well with the excited state vibrating energy of Tb³⁺ ion.     

Synthesis, crystal structure and properties of two ternary rare earth complexes with aromatic acid and 1,10-phenanthroline

Two dimeric rare-earth complexes [Eu(o-MOBA)₃phen]₂·2H₂O (1), [Tb(o-MOBA)₃phen]₂·2H₂O (2), (where o-MOBA = o-methoxybenzoate, phen = 1,10-phenanthroline) were synthesized and structurally characterized. Both of them consist of neutral dimeric molecules, crystallize in triclinic system, space group P. Each RE(III) ion is nine-coordinated with one 1,10-phenanthroline molecule, one bidentate chelating carboxylate group, two bidentate bridging carboxylate groups and two tridentate bridging carboxylate groups. Complex 1 shows bright red luminescence, 2 shows green luminescence under UV light at room temperature, respectively. The thermal analysis indicates that they are all quite stable to heat.     

配合物Cu（phen）（m-CBA）2的合成、晶体结构及磁性（英文）

采用间氯苯甲酸(m-CBA)、1,10-菲罗啉(phen)和醋酸铜合成一种新颖配合物Cu(phen)(m-CBA)2,并用红外光谱、紫外可见光谱、元素分析、X-射线单晶衍射对其进行表征。结果表明,该配合物为单斜晶系,空间群为C2/c,晶胞参数为a=2.9699(4)nm,b=1.15452(2)nm,c=1.5335(2)nm,β=111.118(2)°,V=4.9051(1)nm3,Z=8,F(000)=2328,R1=0.0728,wR2=0.2234[I>2σ(I)]。结果分析表明,中心铜原子和来自1个1,10-菲罗啉分子的2个氮原子、2个间氯苯甲酸分子的2个氧原子进行配位,形成一个变形平面四边形的配位模式。该配合物中铜原子之间存在顺磁相互作用。     

Syntheses,structures, and luminescent properties of cadmium (II) complexes: 3D supramolecular [Cd(phen)(NO3)(NO2)(H2O)]n and Cd(phen)2(NO3)(NO2) constructed by π–π stacking interactions

Two novel complexes [Cd(phen)(NO₃)(NO₂)(H₂O)]_n (1) and Cd(phen)₂(NO₃)(NO₂) (2) (phen = 1,10-phenanthroline) have been synthesized by the reductive reaction of metal source Cd(NO₃)₂·4H₂O with phen and benzidine in the mixed solution of DMF, ethanol and water. Crystal structures of complexes 1 and 2 were determined by single-crystal X-ray diffraction. Complex 1 is a one-dimensional (1D) zig-zag infinite chain in which (phen)Cd^(II) units were bridged by two O atoms of NO₂⁻. The three-dimensional (3D) supramolecular structure of 1 is constructed through hydrogen-bond and aromatic π–π stacking interactions between adjacent metal–organic polymeric coordination chains. Complex 2 is a mononuclear structure, and self-assembled through π–π stacking interactions to form a three-dimensional (3D) supramolecular structure. The complex 1 exhibits luminescent property in the near-UV at room temperature in solutions of DMSO and DMF with the emission energy following the order DMF < DMSO, which might be ascribed to the presence of a highly polarized ground state. Complexes 1 and 2 have blue-purple luminescence at room temperature in the solid state. The blue-purple luminescence of the complexes is due to π* → π transition of phen.     

Spectroscopic studies of the Eu(III) and Gd(III) tris(3-aminopyridine-2-carboxylic acid) complexes

The synthesis and spectroscopic studies of the complexes of Eu(III) and Gd(III) with 3-aminopyridine-2-carboxylic acid (3-NH₂pic) are described. An experimental and theoretical analysis of the intensities of the ⁵D₀→⁷F_0,1,2,4 transitions of the Eu(III) ion is presented. An approximate structure for the Eu(III) complex is assumed and the theoretical calculations are based on a model, previously described, which takes into account the forced electric dipole and dynamic coupling mechanisms.     

Non-isothermal kinetics of the first-stage decomposition reaction of the complex of samarium p-methoxybenzoate with 1,10-phenanthroline

The complex of [Sm(p-MOBA)3phen]2 (p-MOBA, p-methoxybenzoate; phen, 1,10-phenanthroline) was pre- pared and characterized by elemental analysis, IR, and UV spectroscopy. The thermal decomposition of the [Sm(p-MOBA)3phen]2 complex and its kinetics were studied under a static air atmosphere by TG-DTG methods. The in- termediate and residue for each decomposition stage were identified from the TG curve. The kinetic parameters and mecha- nisms of the first decomposition stage were obtained from the analysis of the TG-DTG curves by a new method of process- ing the data of thermal analysis kinetics. The lifetime equation at a mass loss of 10% was deduced as lnτ = – 30.6795 21034.56/T by isothermal thermogravimetric analysis.     

双(二叔丁基苯基膦)二卤化Pt(Ⅱ)配合物的合成及结构测试

采用铂替代钯合成了以二叔丁基苯基膦[(t-Bu)_2PPh]和卤素(Cl、Br)为配体的Pt(Ⅱ)配合物。以氯化铂(PtCl_2)和溴化铂(PtBr_2)为起始原料,二甲亚砜(DMSO)为溶剂,在氮气保护下与二叔丁基苯基膦反应,得到目标化合物。结果表明,Pt[(t-Bu)_2PPh]_2Cl_2产率为96.9%,Pt[(t-Bu)_2PPh]_2Br_2产率为94.1%,2种化合物的纯度均大于99%。通过元素分析、核磁共振(~1H-NMR)分析和单晶X射线衍射(XRD)分析测定了目标化合物的化学结构,结果显示,配合物均为trans-四配位的平面正方形配合物,Pt(Ⅱ)处于配位平面的中心,分别与2个Cl或者Br和P键合,形成4配位的平面四边形的结构,2个卤素原子和膦配体处于反位。     

Standard energies of combustion and standard enthalpies of formation for the complexes RE （Et2dtc）3（phen） （RE = Ho, Er, Tm, Yb, Lu）

The treatment of RECl3.xH2O （RE = Ho, Er, Tm, Yb, Lu; x = 3-4） with sodium diethyldithiocarbamate （NaEtEdtc-3H2O） and 1,10-phenanthroline hydrate （o-phen.H2O） in absolute ethanol yielded five ternary solid complexes RE（EtEdtC）a（phen）. IR spectra of the complexes showed that RE^3＋ coordinated to two sulfur atoms in NaEt2dtc and two nitrogen atoms in o-phen. The constant-volume energies of combustion of the complexes have been determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion and standard enthalpies of formation were calculated.