New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carb...New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.展开更多
Two complexes [Eu2(2-TFMBA)6(2,2′-bipy)2]·2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2′-bipy=2,2′-bipyridine; 1,10-phen= 1,10-phenanthroline) were synth...Two complexes [Eu2(2-TFMBA)6(2,2′-bipy)2]·2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2′-bipy=2,2′-bipyridine; 1,10-phen= 1,10-phenanthroline) were synthesized by solvent method and determined by X-ray diffraction analysis. Complex 1 crystallizes in monoclinic system with space group P21/c, whereas complex 2 crystallizes in triclinic system with space group Pi. Both are binuclear molecules with an inversion center. In complex 1, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in bidentate-bridging mode. Each Eu^3+ ion is eight-coordinated with six O atoms from five 2-TFMBA ligands and two N atoms from one 2,2′-bipy molecule. In complex 2, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in two modes, namely, bidentate-bridging and tridentate-bridging. Each Eu^3+ ion is nine-coordinated with seven O atoms from five 2-TFMBA ligands and two N atoms from one 1,10-phen molecule. The two complexes both exhibited strong red fluorescence under ultraviolet light, and the ^5D0→^7Fj (j=0-4) transition emissions of Eu^3+ ion were observed in their emission spectra.展开更多
The strong photoluminescence properties of europium complexes with organic ligands attracted the attention of many researchers and found a wide range of uses in medical, industrial and biological fields. In this artic...The strong photoluminescence properties of europium complexes with organic ligands attracted the attention of many researchers and found a wide range of uses in medical, industrial and biological fields. In this article, four new Tetrakis europium complexes <b>3a</b>, <b>3b</b>, <b>3c</b> and <b>3d</b> have been prepared using 1-phenyl-4,4,4-trifluoro-1,3-butenedionato ligand and pyridinium, bipyridinium, piperazinium and piperidinium counter cations. These complexes have been characterized by negative FAB-mass. The crystal structures of <b>3a</b>, <b>3b</b>, <b>3c</b> and <b>3d</b> were determined by single crystal X-ray diffraction analysis. The complex <b>3a</b> crystallized in monoclinic form, space group <i>P</i>2<sub>1</sub>/<i>n </i><span>with four molecules in the unit cell.<i> </i>The complex <b>3b</b> crystallized in monoclinic form, space group <i>P</i>2/<i>n </i><span>with two complex molecules in the unit cell.<i> </i>The complex <b>3c</b> crystallized in monoclinic form, space group <i>C</i>2/<i>c </i><span>with sixteen molecules in the unit cell.<i> </i>The complex <b>3d</b> crystallized in monoclinic form, space group <i>P</i>2<sub>1</sub>/<i>n </i><span>with four complex molecules in the unit cell. The complex <b>3a</b> has 1,2-alternative structure, <b>3b</b> has 1,3-alternative structure, <b>3c </b>has cone like structure and <b>3d</b> has partial cone like structure. The photoluminescence properties of these complexes have been evaluated. Strong red emissions were observed in all four complexes due to <sup>5</sup>D<sub>0</sub> → <sup>7</sup>F<sub>2</sub> transition of Europium (III) ions under UV excitation. Four <i>β</i>-diketone ligands acted as strong antenna ligands and transferred the absorbed energy to europium (III) ion effectively;consequently strong red luminescence was observed.展开更多
The research on electroluminescence based on europium(III) complexes has come to an important phase. This article reviewed the progresses in photoluminescence and electrohiminescence of Eu(III) complexes in recent...The research on electroluminescence based on europium(III) complexes has come to an important phase. This article reviewed the progresses in photoluminescence and electrohiminescence of Eu(III) complexes in recent years from the views of the design of Eu(III) complexes and optimization of device structures, and discussed some important factors influencing electroluminescence performance. The problems existing in the practical application such as the volatility and thermal stability of Eu(III) complexes in this area were discussed, and the possible corresponding solutions were briefly prospected.展开更多
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 indic...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 Tb0.5 RE0.5(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.展开更多
Europium and terbium complexes with strong fluorescence intensity and long fluorescence lifetime were prepared. By replacing half of the europium or terbium ion with M (M = Zn^2+, Cd^2+, and Cr^3+) using the dope...Europium and terbium complexes with strong fluorescence intensity and long fluorescence lifetime were prepared. By replacing half of the europium or terbium ion with M (M = Zn^2+, Cd^2+, and Cr^3+) using the doped method, and then incorporating it with 18-crown-6 ether and terephthalic acid, six heteronuclear samples EuZnLL'Cl3·3H2O(1), EuCdLL2'Cl3·5H2O(2), EuCrLL'Cl4· 4H2O(3), TbZnLL'Cl3·4H2O(4), TbCdLL'2Cl3·4H2O(5), and TbCrLL'2Cl4 ·4H2O(6) (L = terephthalic acid, L'= 18-Crown-6 ether) were obtained. The elemental analysis, molar conductivities, rare earth complexometry, Fourier Transform Infrared Spectroscopy (FT-IR), ultraviolet (UV), TGA, fluorescence intensity, and fluorescence lifetime of the samples were measured. The results showed that there were good luminescence properties for heteronuclear complexes (1), (2), (4), and (5), which were even stronger than those of the homonuclear complexes Eu2LL'2Cl4·4H2O and Tb2LL'2Cl4 ·4H2O, but the luminescence properties of EuCrLL'Cl4·4H2O, TbCrLL'Cl4·4H2O were very weak. A possible luminescence mechanism was suggested by the organic-inorganic doped mechanism and the law of intramolecular energy transfer.展开更多
Seven ternary Eu (m) complexes were synthesized with aromatic carboxylic acid (benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid) as the first ligand and 1,10-phenanthro- line or 2,2'-dipyri...Seven ternary Eu (m) complexes were synthesized with aromatic carboxylic acid (benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid) as the first ligand and 1,10-phenanthro- line or 2,2'-dipyridyl as the second ligand. The ternary Eu( Ⅲ ) complexes were characterized by elemental analysis, IR and TG-DTG methods. In these complexes, the Eu (Ⅲ) ions are bonded to the oxygen atoms of carboxylate and the nitrogen atoms of neutral ligands. Four complexes whose second ligand is 1,10- phenanthrolin have fine thermal stability. Excitation and luminescence spectra of the tide complexes reveal that the fluorescence of the complexes in which 1,10- phenanthrolin as the second ligand are more intensive than those complexes in which 2, 2'-dipyridyl as the second ligand. The order of the strongest emission peak of seven ternary complexes is: Eu(β-PPA)3phen 〉 Eu(BA)3phen 〉 Eu(PLA)3phen 〉 Eu(BA)3bipy 〉 Eu ( PEA)3bipy 〉 Eu ( CA )3phen · H2O 〉 Eu ( CA )3bipy (BA : benzoic ; PEA : phenylacetic ; β-PPA :展开更多
Silica gel luminophors containing 1, 10-phenanthroline-tris(M-Methylbenzoate) europium (or terbium) com- plexes were prepared bysol-gel method. The thermal decomposition, excitation and emissionspectra for the gel pho...Silica gel luminophors containing 1, 10-phenanthroline-tris(M-Methylbenzoate) europium (or terbium) com- plexes were prepared bysol-gel method. The thermal decomposition, excitation and emissionspectra for the gel phos- phors were measured and compared with thatof solid complex powders. The thermal stability of the complexes wasen- hanced in SiO_2 host matrix and the luminescence intensityremained unchanged.展开更多
Using 2'-Hydroxyacetophenone and as the raw material, 1-( 2-Hydroxyphenyl )-3-Phenyl-1, 3- Propanedione (HPPPD) was synthesized by esterification reaction and Fries rearrangement reaction. And the complexes of HP...Using 2'-Hydroxyacetophenone and as the raw material, 1-( 2-Hydroxyphenyl )-3-Phenyl-1, 3- Propanedione (HPPPD) was synthesized by esterification reaction and Fries rearrangement reaction. And the complexes of HPPPD with europium were also synthesized. The compounds were characterized by IR, thermo-gravimetric analysis and ^1H-NMR. The effects of phenolic hydroxyl on the luminescence properties of complexes were studied. The results show that the complexes emit strong red fluorescence and the fluorescence intensity of the ternary complex is better than that of the duality. But the complexes of HPPPD with Sm( Ⅲ ), Tb ( Ⅲ ), Dy ( Ⅲ ) emit weak fluorescence. The phenomenon was interpreted by electron-effect and energy-matching mechanism. Energy transfer mechanism of the luminescence in the complex was discussed.展开更多
A europium lanthanum hetero nuclear complex with new ligand N, N′ dimethyl N, N′ diphenyladipamide (MPAA) was prepared. The one dimensional chain structure of [La 0.5 Eu 0.5 (MPAA) 2(NO 3) 3] was det...A europium lanthanum hetero nuclear complex with new ligand N, N′ dimethyl N, N′ diphenyladipamide (MPAA) was prepared. The one dimensional chain structure of [La 0.5 Eu 0.5 (MPAA) 2(NO 3) 3] was determined crystallographicaly. The europium ion and lanthanum ion statistically lie at the position of the metal ion with M=1/2(La+Eu). Each Ln 3+ ion is nine coordinated including three bidentate nitrates, three carboxyl groups from three MPAA molecules, in which two MPAA are act as bridge ligand. The intensity of fluorescence of La 3+ Eu 3+ heteronuclear complex A was obviously higher than that of pure Eu 3+ complex B both in solution and in solid state.展开更多
The luminescent properties of four pyridine carboxylic acid-europium complexes were investigated by infrared absorption,fluorescence and time-resolved fluorescent spectroscopy.The influences of structure of complex co...The luminescent properties of four pyridine carboxylic acid-europium complexes were investigated by infrared absorption,fluorescence and time-resolved fluorescent spectroscopy.The influences of structure of complex compounds,solvents and pH of the media on the emission intensity and the lifetime are discussed as well.展开更多
Three new 1,10-phenanthroline derivatives, dipyrido (3,2-f: 2,3-h) quinoxaline (DPQN), imidazo (5,6-f)-(1,10)-phenanthroline (IP) and 3-phenyl-imidazo (5,6-f)-(1,10)-phenanthroline (PIP) were designed and synthesized ...Three new 1,10-phenanthroline derivatives, dipyrido (3,2-f: 2,3-h) quinoxaline (DPQN), imidazo (5,6-f)-(1,10)-phenanthroline (IP) and 3-phenyl-imidazo (5,6-f)-(1,10)-phenanthroline (PIP) were designed and synthesized as a secondary ligand to coordinate with europium (Ⅲ) ion while dibenzoylmethane (DBM) was used as the first ligand. The compositions of the ligands and the europium (Ⅲ) ternary complexes were confirmed by elementary analysis, IR and (()~1H-NMR) spectroscopy. The UV-visible absorption spectra, thermal stability, photoluminescence spectra, quantum yield and fluorescence life time of the Eu(Ⅲ) complexes were investigated. The effect of the structure of the secondary ligand on the photoluminescence of the complexes was discussed. The results show that the synthesized Eu(Ⅲ) complexes are good red-emitiing materials for potential application in fabrication of organic electroluminescence devices.展开更多
A series of euroPium(Ⅱ)eomPlexes with earboxylie aeids andl,10-Phenantl飞ro-line:Eu(L):·pllen·jHoO,wl:ereL-formate,3-hydroxy-4-metlloxybenzoate,4一metl、oxybenzoate,4一ehloroPhenoxyaeetate,and diPI、enylaee...A series of euroPium(Ⅱ)eomPlexes with earboxylie aeids andl,10-Phenantl飞ro-line:Eu(L):·pllen·jHoO,wl:ereL-formate,3-hydroxy-4-metlloxybenzoate,4一metl、oxybenzoate,4一ehloroPhenoxyaeetate,and diPI、enylaeetate,were synthesizedand el、araeterized by elemental analysis,UV sPeetrum,IR speetrum and melting point.IR da亡a eonfirmed tllat euroPium 15 eoordinated wirh 0 donor atoms in earboxy!ie aeidand N donor atoms inl,10一phenanthroline.A strong ligand一loealized absorption at270 nm!ed to a series of meta!一eentered emission bands between 580 and 710 nm as-signedto ~5D_0-7F_(0.1.2.3.)展开更多
Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only ...Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only a few complexes of Cu(I)have been published^(1-3).The title complex Cu_2(C_5H_4N·CH=CH_2)_3Cl was prepared and characterized by elemental analyses,ICP,IR,and electronic spectra.Its conductivity,oxidation potential and reduction potential were measured.展开更多
Three new heterotrinuclear complexes have been synthesized and characterized, namely {[Gd(L)(2)](2)[Cu(pbaOH)]}(ClO4)(4), where pbaOH denotes 2-hydroxy-1,3-propylenebis(oxamato), L stands for 1,10-phenanthroline (phen...Three new heterotrinuclear complexes have been synthesized and characterized, namely {[Gd(L)(2)](2)[Cu(pbaOH)]}(ClO4)(4), where pbaOH denotes 2-hydroxy-1,3-propylenebis(oxamato), L stands for 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (NO2-phen) or 2,2'-bipyridyl (bpy). The temperature dependence of the magnetic susceptibility of ([Gd(phen)(2)(ClO4)](2)[Cu(pbaOH)])(ClO4)(2) has been studied in the 4-300K range, giving the exchange integral J = 6.69 cm(-1). This indicates a weak ferromagnetic interaction between the copper(II) and gadolinium(III) ions.展开更多
A series of europium(III) complexes with different chain length, tris [2-m-pyridylmethanamido-5-phenyl- (1,3,4)-oxadiazole] mono [2-(4-n-alkylphenyl)-iminazole (4,5-f)-1,10-phenanthroline] Eu(III) [Eu(PMA)3Nn (n = 6, ...A series of europium(III) complexes with different chain length, tris [2-m-pyridylmethanamido-5-phenyl- (1,3,4)-oxadiazole] mono [2-(4-n-alkylphenyl)-iminazole (4,5-f)-1,10-phenanthroline] Eu(III) [Eu(PMA)3Nn (n = 6, 10, 14,18)] were synthesized. All of these amphiphilic europium(III) complexes could form stable Langmuir film at air/water interface and could be transferred onto hydrophilic quartz and mica substrates by measurement of UV spectra in which the absorbance of the LB films at about 288 nm scales showed the linearity with the number of layers deposited. In order to investigate relation between fluorescence properties and the arrangement of molecular in LB films, surface topography of monolayer films were observed by atomic force microscopy (AFM). Results showed that the emission spectra have Eu(III) characteristic peaks and strong emission strength. It is interesting that the molecular with looser arrangement in LB films has better monochromacity, which illustrated that energy might transferred more easily from ligand to Eu(III) in loosen structure films.展开更多
A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, a...A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.展开更多
The LB film of the title complex was prepared by dropping a benzene solution of the title complex on the surfaceof water subphase at 25±1℃.The film was deposited in Z type on various hydrophilic pretreated subst...The LB film of the title complex was prepared by dropping a benzene solution of the title complex on the surfaceof water subphase at 25±1℃.The film was deposited in Z type on various hydrophilic pretreated substrates ofquartz,CaF;and electronic conductive glass for different purposes.The π-A curve of the film shows that thecross section per molecule is 125;,which indicates that the alkyl chain of the molecule is basically perpendiculalto the surface of the substrate.UV,IR spectra and transmission electronic microscopy of the film were also obtained.展开更多
A series of binuclear complexes with different molar ratio of europium to yttrium with cinnamic acid and o phenanthroline were synthesized in anhydrous alcohol. Elemental analysis shows that the composition of the co...A series of binuclear complexes with different molar ratio of europium to yttrium with cinnamic acid and o phenanthroline were synthesized in anhydrous alcohol. Elemental analysis shows that the composition of the complexes are Eu x Y 1- x (phen)L 3 (L: C 6H 5CH=CHCOO, x =1.0, 0.7, 0.5, 0.3 and 0.1). The IR absorption spectra indicate that cinnamate is coordinated to the rare earth ions and chemical bonds are formed between rare earth ions and nitrogen atoms of o phenanthroline. Fluorescent spectra show that the emission of Eu 3+ ion can be greatly enhanced if some of europium ions in the complexes are substituted by yttrium ions.展开更多
Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the m...Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the monoclinic system,P21/c space group.The data for 1:a = 1.6964(3),b = 1.02149(17),c = 2.5650(3) nm,β = 121.824(8)°,Z = 4,V = 3.7766(10) nm^3,Dc = 1.293 g·cm^-3,F(000) = 1536,μ = 1.082 mm^-1,the final R = 0.0500,wR = 0.1562 and S =1.072.The data for 2:a = 1.6802(9),b = 1.0256(6),c = 2.5083(10) nm,β = 121.77(3)°,Z = 4,V = 3.675(3) nm^3,Dc = 1.486 g·cm^-3,F(000) = 1664,μ = 5.159 mm^-1,the final R = 0.0481,wR = 0.1055 and S =1.076.The coordinated geometry of the central M(III) with six sulfur atoms from three ligands is a distorted pentagonal pyramid configuration.The dimer structural system is formed by the weak interactions of M…S and C-H…S between two molecules.The complexes were valued for their antibacterial activities by agar-streak method.It was found that 1 is active against the four test bacterial organisms.展开更多
文摘New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.
基金supported by the Natural Science Foundation of Beijing (2073022)
文摘Two complexes [Eu2(2-TFMBA)6(2,2′-bipy)2]·2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2′-bipy=2,2′-bipyridine; 1,10-phen= 1,10-phenanthroline) were synthesized by solvent method and determined by X-ray diffraction analysis. Complex 1 crystallizes in monoclinic system with space group P21/c, whereas complex 2 crystallizes in triclinic system with space group Pi. Both are binuclear molecules with an inversion center. In complex 1, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in bidentate-bridging mode. Each Eu^3+ ion is eight-coordinated with six O atoms from five 2-TFMBA ligands and two N atoms from one 2,2′-bipy molecule. In complex 2, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in two modes, namely, bidentate-bridging and tridentate-bridging. Each Eu^3+ ion is nine-coordinated with seven O atoms from five 2-TFMBA ligands and two N atoms from one 1,10-phen molecule. The two complexes both exhibited strong red fluorescence under ultraviolet light, and the ^5D0→^7Fj (j=0-4) transition emissions of Eu^3+ ion were observed in their emission spectra.
文摘The strong photoluminescence properties of europium complexes with organic ligands attracted the attention of many researchers and found a wide range of uses in medical, industrial and biological fields. In this article, four new Tetrakis europium complexes <b>3a</b>, <b>3b</b>, <b>3c</b> and <b>3d</b> have been prepared using 1-phenyl-4,4,4-trifluoro-1,3-butenedionato ligand and pyridinium, bipyridinium, piperazinium and piperidinium counter cations. These complexes have been characterized by negative FAB-mass. The crystal structures of <b>3a</b>, <b>3b</b>, <b>3c</b> and <b>3d</b> were determined by single crystal X-ray diffraction analysis. The complex <b>3a</b> crystallized in monoclinic form, space group <i>P</i>2<sub>1</sub>/<i>n </i><span>with four molecules in the unit cell.<i> </i>The complex <b>3b</b> crystallized in monoclinic form, space group <i>P</i>2/<i>n </i><span>with two complex molecules in the unit cell.<i> </i>The complex <b>3c</b> crystallized in monoclinic form, space group <i>C</i>2/<i>c </i><span>with sixteen molecules in the unit cell.<i> </i>The complex <b>3d</b> crystallized in monoclinic form, space group <i>P</i>2<sub>1</sub>/<i>n </i><span>with four complex molecules in the unit cell. The complex <b>3a</b> has 1,2-alternative structure, <b>3b</b> has 1,3-alternative structure, <b>3c </b>has cone like structure and <b>3d</b> has partial cone like structure. The photoluminescence properties of these complexes have been evaluated. Strong red emissions were observed in all four complexes due to <sup>5</sup>D<sub>0</sub> → <sup>7</sup>F<sub>2</sub> transition of Europium (III) ions under UV excitation. Four <i>β</i>-diketone ligands acted as strong antenna ligands and transferred the absorbed energy to europium (III) ion effectively;consequently strong red luminescence was observed.
基金supported by the National Basic Research Program (2006CB601103)the National Natural Science Foundation of China (20221101, 20423005, 20471004, 90401028, 50372002, 20671006)
文摘The research on electroluminescence based on europium(III) complexes has come to an important phase. This article reviewed the progresses in photoluminescence and electrohiminescence of Eu(III) complexes in recent years from the views of the design of Eu(III) complexes and optimization of device structures, and discussed some important factors influencing electroluminescence performance. The problems existing in the practical application such as the volatility and thermal stability of Eu(III) complexes in this area were discussed, and the possible corresponding solutions were briefly prospected.
基金Project supported by the National Natural Science Foundation of China (20461002)Chunhui Plan of MOE (Z2004-2-15029)
文摘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 Tb0.5 RE0.5(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.
基金Project supported by the National Natural Science Foundation of China (20461002) Chun Hui Plan Foundation of MOE(Z2004-2-15029)
文摘Europium and terbium complexes with strong fluorescence intensity and long fluorescence lifetime were prepared. By replacing half of the europium or terbium ion with M (M = Zn^2+, Cd^2+, and Cr^3+) using the doped method, and then incorporating it with 18-crown-6 ether and terephthalic acid, six heteronuclear samples EuZnLL'Cl3·3H2O(1), EuCdLL2'Cl3·5H2O(2), EuCrLL'Cl4· 4H2O(3), TbZnLL'Cl3·4H2O(4), TbCdLL'2Cl3·4H2O(5), and TbCrLL'2Cl4 ·4H2O(6) (L = terephthalic acid, L'= 18-Crown-6 ether) were obtained. The elemental analysis, molar conductivities, rare earth complexometry, Fourier Transform Infrared Spectroscopy (FT-IR), ultraviolet (UV), TGA, fluorescence intensity, and fluorescence lifetime of the samples were measured. The results showed that there were good luminescence properties for heteronuclear complexes (1), (2), (4), and (5), which were even stronger than those of the homonuclear complexes Eu2LL'2Cl4·4H2O and Tb2LL'2Cl4 ·4H2O, but the luminescence properties of EuCrLL'Cl4·4H2O, TbCrLL'Cl4·4H2O were very weak. A possible luminescence mechanism was suggested by the organic-inorganic doped mechanism and the law of intramolecular energy transfer.
文摘Seven ternary Eu (m) complexes were synthesized with aromatic carboxylic acid (benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid) as the first ligand and 1,10-phenanthro- line or 2,2'-dipyridyl as the second ligand. The ternary Eu( Ⅲ ) complexes were characterized by elemental analysis, IR and TG-DTG methods. In these complexes, the Eu (Ⅲ) ions are bonded to the oxygen atoms of carboxylate and the nitrogen atoms of neutral ligands. Four complexes whose second ligand is 1,10- phenanthrolin have fine thermal stability. Excitation and luminescence spectra of the tide complexes reveal that the fluorescence of the complexes in which 1,10- phenanthrolin as the second ligand are more intensive than those complexes in which 2, 2'-dipyridyl as the second ligand. The order of the strongest emission peak of seven ternary complexes is: Eu(β-PPA)3phen 〉 Eu(BA)3phen 〉 Eu(PLA)3phen 〉 Eu(BA)3bipy 〉 Eu ( PEA)3bipy 〉 Eu ( CA )3phen · H2O 〉 Eu ( CA )3bipy (BA : benzoic ; PEA : phenylacetic ; β-PPA :
基金This project is financially supported by Natural Science Foundation of Hebei Province, China (No. 299193)
文摘Silica gel luminophors containing 1, 10-phenanthroline-tris(M-Methylbenzoate) europium (or terbium) com- plexes were prepared bysol-gel method. The thermal decomposition, excitation and emissionspectra for the gel phos- phors were measured and compared with thatof solid complex powders. The thermal stability of the complexes wasen- hanced in SiO_2 host matrix and the luminescence intensityremained unchanged.
文摘Using 2'-Hydroxyacetophenone and as the raw material, 1-( 2-Hydroxyphenyl )-3-Phenyl-1, 3- Propanedione (HPPPD) was synthesized by esterification reaction and Fries rearrangement reaction. And the complexes of HPPPD with europium were also synthesized. The compounds were characterized by IR, thermo-gravimetric analysis and ^1H-NMR. The effects of phenolic hydroxyl on the luminescence properties of complexes were studied. The results show that the complexes emit strong red fluorescence and the fluorescence intensity of the ternary complex is better than that of the duality. But the complexes of HPPPD with Sm( Ⅲ ), Tb ( Ⅲ ), Dy ( Ⅲ ) emit weak fluorescence. The phenomenon was interpreted by electron-effect and energy-matching mechanism. Energy transfer mechanism of the luminescence in the complex was discussed.
文摘A europium lanthanum hetero nuclear complex with new ligand N, N′ dimethyl N, N′ diphenyladipamide (MPAA) was prepared. The one dimensional chain structure of [La 0.5 Eu 0.5 (MPAA) 2(NO 3) 3] was determined crystallographicaly. The europium ion and lanthanum ion statistically lie at the position of the metal ion with M=1/2(La+Eu). Each Ln 3+ ion is nine coordinated including three bidentate nitrates, three carboxyl groups from three MPAA molecules, in which two MPAA are act as bridge ligand. The intensity of fluorescence of La 3+ Eu 3+ heteronuclear complex A was obviously higher than that of pure Eu 3+ complex B both in solution and in solid state.
文摘The luminescent properties of four pyridine carboxylic acid-europium complexes were investigated by infrared absorption,fluorescence and time-resolved fluorescent spectroscopy.The influences of structure of complex compounds,solvents and pH of the media on the emission intensity and the lifetime are discussed as well.
文摘Three new 1,10-phenanthroline derivatives, dipyrido (3,2-f: 2,3-h) quinoxaline (DPQN), imidazo (5,6-f)-(1,10)-phenanthroline (IP) and 3-phenyl-imidazo (5,6-f)-(1,10)-phenanthroline (PIP) were designed and synthesized as a secondary ligand to coordinate with europium (Ⅲ) ion while dibenzoylmethane (DBM) was used as the first ligand. The compositions of the ligands and the europium (Ⅲ) ternary complexes were confirmed by elementary analysis, IR and (()~1H-NMR) spectroscopy. The UV-visible absorption spectra, thermal stability, photoluminescence spectra, quantum yield and fluorescence life time of the Eu(Ⅲ) complexes were investigated. The effect of the structure of the secondary ligand on the photoluminescence of the complexes was discussed. The results show that the synthesized Eu(Ⅲ) complexes are good red-emitiing materials for potential application in fabrication of organic electroluminescence devices.
基金Supported by the National Natural Science Foundation of China, St. Michael's College the National Science Foundation, R11-8610679(Vermont EPSCOR), U. S. A.
文摘A series of euroPium(Ⅱ)eomPlexes with earboxylie aeids andl,10-Phenantl飞ro-line:Eu(L):·pllen·jHoO,wl:ereL-formate,3-hydroxy-4-metlloxybenzoate,4一metl、oxybenzoate,4一ehloroPhenoxyaeetate,and diPI、enylaeetate,were synthesizedand el、araeterized by elemental analysis,UV sPeetrum,IR speetrum and melting point.IR da亡a eonfirmed tllat euroPium 15 eoordinated wirh 0 donor atoms in earboxy!ie aeidand N donor atoms inl,10一phenanthroline.A strong ligand一loealized absorption at270 nm!ed to a series of meta!一eentered emission bands between 580 and 710 nm as-signedto ~5D_0-7F_(0.1.2.3.)
文摘Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only a few complexes of Cu(I)have been published^(1-3).The title complex Cu_2(C_5H_4N·CH=CH_2)_3Cl was prepared and characterized by elemental analyses,ICP,IR,and electronic spectra.Its conductivity,oxidation potential and reduction potential were measured.
文摘Three new heterotrinuclear complexes have been synthesized and characterized, namely {[Gd(L)(2)](2)[Cu(pbaOH)]}(ClO4)(4), where pbaOH denotes 2-hydroxy-1,3-propylenebis(oxamato), L stands for 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (NO2-phen) or 2,2'-bipyridyl (bpy). The temperature dependence of the magnetic susceptibility of ([Gd(phen)(2)(ClO4)](2)[Cu(pbaOH)])(ClO4)(2) has been studied in the 4-300K range, giving the exchange integral J = 6.69 cm(-1). This indicates a weak ferromagnetic interaction between the copper(II) and gadolinium(III) ions.
文摘A series of europium(III) complexes with different chain length, tris [2-m-pyridylmethanamido-5-phenyl- (1,3,4)-oxadiazole] mono [2-(4-n-alkylphenyl)-iminazole (4,5-f)-1,10-phenanthroline] Eu(III) [Eu(PMA)3Nn (n = 6, 10, 14,18)] were synthesized. All of these amphiphilic europium(III) complexes could form stable Langmuir film at air/water interface and could be transferred onto hydrophilic quartz and mica substrates by measurement of UV spectra in which the absorbance of the LB films at about 288 nm scales showed the linearity with the number of layers deposited. In order to investigate relation between fluorescence properties and the arrangement of molecular in LB films, surface topography of monolayer films were observed by atomic force microscopy (AFM). Results showed that the emission spectra have Eu(III) characteristic peaks and strong emission strength. It is interesting that the molecular with looser arrangement in LB films has better monochromacity, which illustrated that energy might transferred more easily from ligand to Eu(III) in loosen structure films.
文摘A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.
文摘The LB film of the title complex was prepared by dropping a benzene solution of the title complex on the surfaceof water subphase at 25±1℃.The film was deposited in Z type on various hydrophilic pretreated substrates ofquartz,CaF;and electronic conductive glass for different purposes.The π-A curve of the film shows that thecross section per molecule is 125;,which indicates that the alkyl chain of the molecule is basically perpendiculalto the surface of the substrate.UV,IR spectra and transmission electronic microscopy of the film were also obtained.
基金Project supponed by the National Natural Scence Foundation of China(20061002)
文摘A series of binuclear complexes with different molar ratio of europium to yttrium with cinnamic acid and o phenanthroline were synthesized in anhydrous alcohol. Elemental analysis shows that the composition of the complexes are Eu x Y 1- x (phen)L 3 (L: C 6H 5CH=CHCOO, x =1.0, 0.7, 0.5, 0.3 and 0.1). The IR absorption spectra indicate that cinnamate is coordinated to the rare earth ions and chemical bonds are formed between rare earth ions and nitrogen atoms of o phenanthroline. Fluorescent spectra show that the emission of Eu 3+ ion can be greatly enhanced if some of europium ions in the complexes are substituted by yttrium ions.
基金Project supported by the Science & Technology Innovation Foundation of Henan Province (No. 092102310309)the Natural Science Foundation of Education Department of Henan Province (No. 2011B150025)
文摘Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the monoclinic system,P21/c space group.The data for 1:a = 1.6964(3),b = 1.02149(17),c = 2.5650(3) nm,β = 121.824(8)°,Z = 4,V = 3.7766(10) nm^3,Dc = 1.293 g·cm^-3,F(000) = 1536,μ = 1.082 mm^-1,the final R = 0.0500,wR = 0.1562 and S =1.072.The data for 2:a = 1.6802(9),b = 1.0256(6),c = 2.5083(10) nm,β = 121.77(3)°,Z = 4,V = 3.675(3) nm^3,Dc = 1.486 g·cm^-3,F(000) = 1664,μ = 5.159 mm^-1,the final R = 0.0481,wR = 0.1055 and S =1.076.The coordinated geometry of the central M(III) with six sulfur atoms from three ligands is a distorted pentagonal pyramid configuration.The dimer structural system is formed by the weak interactions of M…S and C-H…S between two molecules.The complexes were valued for their antibacterial activities by agar-streak method.It was found that 1 is active against the four test bacterial organisms.