We focus on the effect of ionic radius of lanthanides and the number of electrons in 4f orbitals on the superconducting temperature in 12442-type iron-based superconductors RbLn_(2)Fe_(4)As_(4)O_(2)(Ln=Sm and Ho).Elec...We focus on the effect of ionic radius of lanthanides and the number of electrons in 4f orbitals on the superconducting temperature in 12442-type iron-based superconductors RbLn_(2)Fe_(4)As_(4)O_(2)(Ln=Sm and Ho).Electronic properties of RbSm_(2)Fe_(4)As_(4)O_(2) and RbHo2Fe4As4O2with the largest differences of ionic radii and numbers of electrons in 4f orbital,and the largest difference of superconducting temperatures by using firstprinciples calculations.We predict that the ground state of RbLn_(2)Fe_(4)As_(4)O_(2) is spin-density-wave-type in-plane striped antiferromagnet,and the magnetic moment around each Fe atom is about 2μB.RbSm_(2)Fe_(4)As_(4)O_(2)has a great influence on the energy band near theΓpoint,and a Dirac-like dispersion energy band appears.This band is mainly contributed by the dz2orbital of Fe,which proves that RbSm_(2)Fe_(4)As_(4)O_(2)has a stronger threedimensionality.At the same time,this extra Fermi surface appears at theΓpoint,which also shows that Sm can effectively enhance the coupling strength within Fe2As2bilayers.This is also confirmed by the charge density differenceρ(RbHo_(2)Fe_(4)As_(4)O_(2))-ρ(RbSm_(2)Fe_(4)As_(4)O_(2)).It increases the internal coupling strength of the bilayer Fe_(2)As2layers,which in turn leads to a higher Tcof RbSm_(2)Fe_(4)As_(4)O_(2)than RbHo_(2)Fe_(4)As_(4)O_(2).Determining the details of their electronic structure,which may be closely related to superconductivity,is crucial to understanding the underlying mechanism.Such microscopic studies provide useful clues for our further research of other hightemperature superconductors.展开更多
Titanium dioxide (TiO<sub>2</sub>) doped with neodymium (Nd) and/or Gadolinium (Gd) rare-earth elements were fabricated into nanotubes via the hydrothermal method in a KOH solution and in-situ doping. Tita...Titanium dioxide (TiO<sub>2</sub>) doped with neodymium (Nd) and/or Gadolinium (Gd) rare-earth elements were fabricated into nanotubes via the hydrothermal method in a KOH solution and in-situ doping. Titanium dioxide nanotubes (TNTs) and in-situ Nd-doped and/or Gd-doped TNTs were characterized with transmission and scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Morphologies indicated a network of aggregated nanotubes. The phase and composition analyses revealed that the lanthanide TNTs had anatase phases with Nd and/or Gd nanoparticles in the TNT lattice. The nanoparticles were uniformly deposited on the surface because of hydroxyl groups on the TNT surfaces, resulting in a very high loading density. The outer diameter and the length of the TNTs increased with doping. The mechanisms for the formation of multiwall TNTs are discussed.展开更多
Lanthanide(Ln^(3+))-doped photon avalanche(PA)upconversion nanoparticles(UCNPs)have great prospects in many frontier applications,such as super-resolution bioimaging,miniaturized lasers,single-molecule tracking,and qu...Lanthanide(Ln^(3+))-doped photon avalanche(PA)upconversion nanoparticles(UCNPs)have great prospects in many frontier applications,such as super-resolution bioimaging,miniaturized lasers,single-molecule tracking,and quantum optics.However,it remains challenging to realize PA in colloidal Ln^(3+)-doped UCNPs at room temperature(RT),due to the deleterious quenching effect associated with the surface and lattice OH^(-)defects.展开更多
Two lanthanide-oxo-cluster polymers were synthesized by hydrothermal reaction using Ln_2O_3 as initial lanthanide materials:[Ln_4(SO_4)_4(OH)_4(H_2O)_7]·_4H_2O(Ln = Er 1,Ho 2),and characterized by PXRD,IR spectra...Two lanthanide-oxo-cluster polymers were synthesized by hydrothermal reaction using Ln_2O_3 as initial lanthanide materials:[Ln_4(SO_4)_4(OH)_4(H_2O)_7]·_4H_2O(Ln = Er 1,Ho 2),and characterized by PXRD,IR spectra,X-ray single-crystal diffraction,2D IR correlation spectra and UV-visible absorption spectra.Single-crystal X-ray analyses reveal that compounds 1 and 2 are isostructural,and they are both crystallized in the orthorhombic system Pccn space group.Compound 1 is a 3D lanthanide cluster polymer based on tetranuclear cubane-like [Er_4(μ_3-OH)_4]^(8+) cations and SO_4^(2-) anions.The overall structure of 1 can be assigned to 6-connected pcu-type topology with the point symbol of(4^(12).6~3).展开更多
Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()1H) NMR and XPS. The results from thi...Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()1H) NMR and XPS. The results from this paper show that the complexes Ln(phen)(SA)3·2H2O or Ln(phen)(CA)3·H2O (Ln=Ce(Ⅲ), Sm(Ⅲ) and Eu(Ⅲ), (phen=1,10-)phenanthroline, SA=Sorbate and CA=Cinnamate) has better anti-inflammatory effect than cerium nitrate and their gremores are steadier than cerium nitrate gremor. And there is a kind of medicament which can replace the cerium nitrate gremor completely in treating burn.展开更多
Six genistein lanthanide complexes, LnL2 (OAc)·nH2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analy...Six genistein lanthanide complexes, LnL2 (OAc)·nH2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.展开更多
Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. ...Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.展开更多
The Schiff base form of the 4-acylpyrazolone ligand was immobilized on the silica surface by reaction of 3-aminopropyl silica with 4-acetyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one in 97% yield, producing grafted s...The Schiff base form of the 4-acylpyrazolone ligand was immobilized on the silica surface by reaction of 3-aminopropyl silica with 4-acetyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one in 97% yield, producing grafted silica with 0.77 mmol/g ligand loading. This surface modified silica was shown to be selective in the adsorption of Yb3+ ions from dilute aqueous solutions, for which 98% adsorption was observed from a 1.0×10-5 mol/L aq. solution at pH 6.7, after 24 h at room temperature. Six other lanthanides studied Eu3+, Gd3+, Nd3+, Tb3+, Sm3+ and La3+ showed moderate to weaker adsorptions of 39%, 28%, 16%, 12%, 11% and 5% respectively under similar conditions.展开更多
In this paper,we report for the first time the controlled synthesis of lanthanide ion(Ln^(3+))-doped tetragonal-phase Na_3Zr F_7 nanocrystals(NCs)via a high-temperature co-precipitation approach.The as-synthesized Na_...In this paper,we report for the first time the controlled synthesis of lanthanide ion(Ln^(3+))-doped tetragonal-phase Na_3Zr F_7 nanocrystals(NCs)via a high-temperature co-precipitation approach.The as-synthesized Na_3Zr F_7 NCs are systematically studied by utilizing the XRD,TEM as well as high-resolution photoluminescence(PL)spectroscopy.The morphology and size for the as-synthesized Na_3Zr F_7 NCs can be finely controlled by changing the experimental parameters such as the amount of precursor,solvent ratio,reaction temperature and time.By utilizing the red-emitting Eu^(3+)ion as an efficient optical/structural probe,the successful hetero-valence doping of Ln^(3+)activators in the lattices of Na_3Zr F_7 NCs is well-established regardless of their different valences and radii between host Zr^(4+)ion and Ln^(3+)dopant.As a result,intense upconversion(UC)luminescence(UCL)ranging from UV to visible and to NIR spectral regions can be readily achieved after the doping of typical UCL couples of Yb^(3+)/Er^(3+),Yb^(3+)/Tm^(3+)and Yb^(3+)/Ho^(3+)into the lattices of Na_3Zr F_7 NCs when excited by using a 980-nm NIR diode laser.展开更多
A chiral lanthanide metal-organic framework based on enantiopure camphoric acid(D-H_2cam), [Nd_3(D-cam)8(H_2O)_4Cl]_n(1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental a...A chiral lanthanide metal-organic framework based on enantiopure camphoric acid(D-H_2cam), [Nd_3(D-cam)8(H_2O)_4Cl]_n(1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) ?, V = 5008.8(4) ?3, M_r = 1333.08, Z = 4, F(000) = 2644, D_c = 1.768 g/cm3, μ(MoKα) = 3.189 mm-1, the final R = 0.0351 and w R = 0.0814(I > 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism(VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.展开更多
Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) i...Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) ions; (2) organic ligand was then loaded into the channels of the Eu3+-exchanged zeolite by gas diffusion procedure. Loading of ligand into the channels of zeolite L was confirmed by element analysis. Luminescence spectroscopy has confirmed that lanthanide complex are formed in the nanochannels of zeolite L crystals. In addition to the sharp emissions of lanthanide ions, broad band ranged from 350~500 nm can also be observed. This study provides alternative method for fabricating full-color display materials.展开更多
Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products we...Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products were characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) spectroscopy. It was found that the synthesized lanthanide fluorides nanoparticles had high purity and crystallinity, and could be well dispersed in organic solvents such as chloroform, toluene etc., which could be closely related to the surface-capping of the nanocrystals by the DDPA molecules. Moreover, the nanocrystals before and after extraction by DDPA showed few differences in the microscopic morphologies. It was implied that DDPA as the extraction agent had good protection to the nanocrystals as well, which could be essential to the commercial application of the titled rare earth nanocrystals as novel multifunctional additives in the fields of lubrication.展开更多
Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial ...Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment.展开更多
The effect of lanthanide and transition metal ions on the fluorescence spectra of theanticoagulation factor(ACF)of snake venom has been studied.It is postulated that the quenching oftryptophan residue fluorescence by ...The effect of lanthanide and transition metal ions on the fluorescence spectra of theanticoagulation factor(ACF)of snake venom has been studied.It is postulated that the quenching oftryptophan residue fluorescence by lanthanide and transition metal ions is caused by the metal ion-inducedconformation change of ACF.展开更多
Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDG...Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction.展开更多
Three novel lanthanide-IN coordination polymers [Ln(IN)3(H2O)2]n (Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate) have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG analysis....Three novel lanthanide-IN coordination polymers [Ln(IN)3(H2O)2]n (Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate) have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG analysis. Single-crystal X-ray diffraction shows that 1, 2 and 3 are isostructural. Crystal data for 1: monoclinic, space group C2/c, a = 15.8384(14), b = 14.2662 (12), c = 9.5073(7) , β = 97.705(4)°, V = 2128.8(3) 3, Z = 4, Dc = 1.724 g/cm3, F(000) = 1084, μ = 2.806 mm-1 and R = 0.0226; Crystal data for 2: monoclinic, space group C2/c, a = 15.7890(3), b = 14.1356(6), c = 9.5152(3) , β = 97.899(2)°, V = 2103.52(12) 3, Z = 4, Dc = 1.784 g/cm3, F(000) = 1100, μ = 3.601 mm-1 and R = 0.0406; Crystal data for 3: monoclinic, space group C2/c, a = 15.802(5), b = 14.242(4), c = 9.513(3) , β = 97.695(5)°, V = 2121.8(10) 3, Z = 4, Dc = 1.735 g/cm3, F(000) = 1088, μ = 3.004 mm-1 and R = 0.0273. In the three compounds, the Ln(III) centers are eight-coordinated with antiprismatic geometry. The Ln(IN)3(H2O)2 unit connects mutually to form a one-dimensional double zigzag chain via isonicotinate oxygen bridging. The infinite chains are further linked by inter-chain hydrogen-bonding to form a three-dimensional supramolecular network.展开更多
A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(...A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), or Gd(Ⅲ) and HAAP=3-{[2-(N-1-phenyl-2,3-dimethylpyrazol-3-in-5-on-4-yl)]hydrazone}pent-2,3,4-trione. The ligand and metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, infrared, far infrared and proton NMR spectral data. The spectral data revealed that the ligand existed in the hydrazo form and coordinated to the metal ion without deprotonation in a neutral tridentate manner, through carbonyl oxygen of pyrazolone ring, hydrazo nitrogen and carbonyl oxygen of the acetylace-tone moiety. The molar conductance values adequately supported their non-electrolytic nature. The ligand and the praseodymium(Ⅲ) complex were subjected to X-ray diffraction studies. Thermal decomposition behavior of the lanthanum(Ⅲ) complex was also examined.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11904319 and 11974354)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ18A040002)。
文摘We focus on the effect of ionic radius of lanthanides and the number of electrons in 4f orbitals on the superconducting temperature in 12442-type iron-based superconductors RbLn_(2)Fe_(4)As_(4)O_(2)(Ln=Sm and Ho).Electronic properties of RbSm_(2)Fe_(4)As_(4)O_(2) and RbHo2Fe4As4O2with the largest differences of ionic radii and numbers of electrons in 4f orbital,and the largest difference of superconducting temperatures by using firstprinciples calculations.We predict that the ground state of RbLn_(2)Fe_(4)As_(4)O_(2) is spin-density-wave-type in-plane striped antiferromagnet,and the magnetic moment around each Fe atom is about 2μB.RbSm_(2)Fe_(4)As_(4)O_(2)has a great influence on the energy band near theΓpoint,and a Dirac-like dispersion energy band appears.This band is mainly contributed by the dz2orbital of Fe,which proves that RbSm_(2)Fe_(4)As_(4)O_(2)has a stronger threedimensionality.At the same time,this extra Fermi surface appears at theΓpoint,which also shows that Sm can effectively enhance the coupling strength within Fe2As2bilayers.This is also confirmed by the charge density differenceρ(RbHo_(2)Fe_(4)As_(4)O_(2))-ρ(RbSm_(2)Fe_(4)As_(4)O_(2)).It increases the internal coupling strength of the bilayer Fe_(2)As2layers,which in turn leads to a higher Tcof RbSm_(2)Fe_(4)As_(4)O_(2)than RbHo_(2)Fe_(4)As_(4)O_(2).Determining the details of their electronic structure,which may be closely related to superconductivity,is crucial to understanding the underlying mechanism.Such microscopic studies provide useful clues for our further research of other hightemperature superconductors.
文摘Titanium dioxide (TiO<sub>2</sub>) doped with neodymium (Nd) and/or Gadolinium (Gd) rare-earth elements were fabricated into nanotubes via the hydrothermal method in a KOH solution and in-situ doping. Titanium dioxide nanotubes (TNTs) and in-situ Nd-doped and/or Gd-doped TNTs were characterized with transmission and scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Morphologies indicated a network of aggregated nanotubes. The phase and composition analyses revealed that the lanthanide TNTs had anatase phases with Nd and/or Gd nanoparticles in the TNT lattice. The nanoparticles were uniformly deposited on the surface because of hydroxyl groups on the TNT surfaces, resulting in a very high loading density. The outer diameter and the length of the TNTs increased with doping. The mechanisms for the formation of multiwall TNTs are discussed.
文摘Lanthanide(Ln^(3+))-doped photon avalanche(PA)upconversion nanoparticles(UCNPs)have great prospects in many frontier applications,such as super-resolution bioimaging,miniaturized lasers,single-molecule tracking,and quantum optics.However,it remains challenging to realize PA in colloidal Ln^(3+)-doped UCNPs at room temperature(RT),due to the deleterious quenching effect associated with the surface and lattice OH^(-)defects.
基金supported by the National Natural Science Foundation of China(No.21473030)the Natural Science Foundation of Fujian Province(No.2013J01041)the Foundation of State Key Laboratory of Structural Chemistry(No.20130012)
文摘Two lanthanide-oxo-cluster polymers were synthesized by hydrothermal reaction using Ln_2O_3 as initial lanthanide materials:[Ln_4(SO_4)_4(OH)_4(H_2O)_7]·_4H_2O(Ln = Er 1,Ho 2),and characterized by PXRD,IR spectra,X-ray single-crystal diffraction,2D IR correlation spectra and UV-visible absorption spectra.Single-crystal X-ray analyses reveal that compounds 1 and 2 are isostructural,and they are both crystallized in the orthorhombic system Pccn space group.Compound 1 is a 3D lanthanide cluster polymer based on tetranuclear cubane-like [Er_4(μ_3-OH)_4]^(8+) cations and SO_4^(2-) anions.The overall structure of 1 can be assigned to 6-connected pcu-type topology with the point symbol of(4^(12).6~3).
文摘Four ternary lanthanide complexes with unsaturated acid and 1,10-phenanthroline are prepared in methanol and characterized by elemental analysis, molar conductance, UV, IR, (()1H) NMR and XPS. The results from this paper show that the complexes Ln(phen)(SA)3·2H2O or Ln(phen)(CA)3·H2O (Ln=Ce(Ⅲ), Sm(Ⅲ) and Eu(Ⅲ), (phen=1,10-)phenanthroline, SA=Sorbate and CA=Cinnamate) has better anti-inflammatory effect than cerium nitrate and their gremores are steadier than cerium nitrate gremor. And there is a kind of medicament which can replace the cerium nitrate gremor completely in treating burn.
文摘Six genistein lanthanide complexes, LnL2 (OAc)·nH2O [Ln=La(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), Gd(Ⅲ), (Tb(Ⅲ),) Dy(Ⅲ); L=genistein; n=4, 7, 8] were synthesized and characterized on the basis of elemental analyses, IR, (()1H) NMR spectra and molar conductivity. The scavenging activity of genistein and five lanthanides complexes on the hydroxyl free radicals (OH·) was also investigated by spectrophotometric methods. The results show that the scavenging activity of the complexes is better than that of the ligand and their scavenging ability can be assembled in the following order: Sm>La>Dy>Eu>Tb>L.
文摘Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.
基金Supported by the National Natural Science Foundation of China(No.21576112)Natural Science Foundation Project of Jilin Province(No.20130521019JH and 20150623024TC-19)+1 种基金Natural Science Foundation Project of the Education Department of Jilin Province(No.[2014]152)the Science and Technology Development Plan of Siping City(2015049)
文摘Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4^(12)·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property.
基金Project supported by US Department of Energy Global Nuclear Energy Partnership (DOE-GNEP) grant DE-FG07-07ID14881
文摘The Schiff base form of the 4-acylpyrazolone ligand was immobilized on the silica surface by reaction of 3-aminopropyl silica with 4-acetyl-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one in 97% yield, producing grafted silica with 0.77 mmol/g ligand loading. This surface modified silica was shown to be selective in the adsorption of Yb3+ ions from dilute aqueous solutions, for which 98% adsorption was observed from a 1.0×10-5 mol/L aq. solution at pH 6.7, after 24 h at room temperature. Six other lanthanides studied Eu3+, Gd3+, Nd3+, Tb3+, Sm3+ and La3+ showed moderate to weaker adsorptions of 39%, 28%, 16%, 12%, 11% and 5% respectively under similar conditions.
基金supported by the Strategic Priority Research Program of CAS(XDB20000000)the NSFC(Nos.21390392,21473205,and 21731006)+1 种基金Youth Innovation Promotion Association of CASthe Natural Science Foundation of Fujian Province(No.2017J01038)
文摘In this paper,we report for the first time the controlled synthesis of lanthanide ion(Ln^(3+))-doped tetragonal-phase Na_3Zr F_7 nanocrystals(NCs)via a high-temperature co-precipitation approach.The as-synthesized Na_3Zr F_7 NCs are systematically studied by utilizing the XRD,TEM as well as high-resolution photoluminescence(PL)spectroscopy.The morphology and size for the as-synthesized Na_3Zr F_7 NCs can be finely controlled by changing the experimental parameters such as the amount of precursor,solvent ratio,reaction temperature and time.By utilizing the red-emitting Eu^(3+)ion as an efficient optical/structural probe,the successful hetero-valence doping of Ln^(3+)activators in the lattices of Na_3Zr F_7 NCs is well-established regardless of their different valences and radii between host Zr^(4+)ion and Ln^(3+)dopant.As a result,intense upconversion(UC)luminescence(UCL)ranging from UV to visible and to NIR spectral regions can be readily achieved after the doping of typical UCL couples of Yb^(3+)/Er^(3+),Yb^(3+)/Tm^(3+)and Yb^(3+)/Ho^(3+)into the lattices of Na_3Zr F_7 NCs when excited by using a 980-nm NIR diode laser.
基金supported by National Natural Science Foundation of China(21401147)Basic Research Program of Natural Science from Shaanxi Provincial Government(2015JQ2032)+2 种基金Scientific Research Program from Education Department of Shaanxi Provincial Government(2013JK0654)Opening Foundation from State Key Laboratory of Coordination Chemistry in Nanjing University(201219)the Program for Distinguished Young Scholars of Xi’an Polytechnic University(201403)
文摘A chiral lanthanide metal-organic framework based on enantiopure camphoric acid(D-H_2cam), [Nd_3(D-cam)8(H_2O)_4Cl]_n(1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) ?, V = 5008.8(4) ?3, M_r = 1333.08, Z = 4, F(000) = 2644, D_c = 1.768 g/cm3, μ(MoKα) = 3.189 mm-1, the final R = 0.0351 and w R = 0.0814(I > 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism(VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.
文摘Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) ions; (2) organic ligand was then loaded into the channels of the Eu3+-exchanged zeolite by gas diffusion procedure. Loading of ligand into the channels of zeolite L was confirmed by element analysis. Luminescence spectroscopy has confirmed that lanthanide complex are formed in the nanochannels of zeolite L crystals. In addition to the sharp emissions of lanthanide ions, broad band ranged from 350~500 nm can also be observed. This study provides alternative method for fabricating full-color display materials.
基金Project supported bythe National Natural Science Foundation of China (20401006)Natural Science Foundation of Henan Province (200510475019)
文摘Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products were characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) spectroscopy. It was found that the synthesized lanthanide fluorides nanoparticles had high purity and crystallinity, and could be well dispersed in organic solvents such as chloroform, toluene etc., which could be closely related to the surface-capping of the nanocrystals by the DDPA molecules. Moreover, the nanocrystals before and after extraction by DDPA showed few differences in the microscopic morphologies. It was implied that DDPA as the extraction agent had good protection to the nanocrystals as well, which could be essential to the commercial application of the titled rare earth nanocrystals as novel multifunctional additives in the fields of lubrication.
文摘Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment.
基金Project supported by the National Natural Science Foundation of China
文摘The effect of lanthanide and transition metal ions on the fluorescence spectra of theanticoagulation factor(ACF)of snake venom has been studied.It is postulated that the quenching oftryptophan residue fluorescence by lanthanide and transition metal ions is caused by the metal ion-inducedconformation change of ACF.
基金supported by the National Natural Science Foundation of China(21077044)Natural Science Foundation of Shandong Province(ZR2015BM030)
文摘Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction.
基金This work was supported by the NNSFC (Nos. 20271050 and 20473093), the Talents Program of the Chinese Academy of Sciences and NSF of Fujian Province (Nos. E0510030, E0210029 and 2005HZ01-1)
文摘Three novel lanthanide-IN coordination polymers [Ln(IN)3(H2O)2]n (Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate) have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG analysis. Single-crystal X-ray diffraction shows that 1, 2 and 3 are isostructural. Crystal data for 1: monoclinic, space group C2/c, a = 15.8384(14), b = 14.2662 (12), c = 9.5073(7) , β = 97.705(4)°, V = 2128.8(3) 3, Z = 4, Dc = 1.724 g/cm3, F(000) = 1084, μ = 2.806 mm-1 and R = 0.0226; Crystal data for 2: monoclinic, space group C2/c, a = 15.7890(3), b = 14.1356(6), c = 9.5152(3) , β = 97.899(2)°, V = 2103.52(12) 3, Z = 4, Dc = 1.784 g/cm3, F(000) = 1100, μ = 3.601 mm-1 and R = 0.0406; Crystal data for 3: monoclinic, space group C2/c, a = 15.802(5), b = 14.242(4), c = 9.513(3) , β = 97.695(5)°, V = 2121.8(10) 3, Z = 4, Dc = 1.735 g/cm3, F(000) = 1088, μ = 3.004 mm-1 and R = 0.0273. In the three compounds, the Ln(III) centers are eight-coordinated with antiprismatic geometry. The Ln(IN)3(H2O)2 unit connects mutually to form a one-dimensional double zigzag chain via isonicotinate oxygen bridging. The infinite chains are further linked by inter-chain hydrogen-bonding to form a three-dimensional supramolecular network.
文摘A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), or Gd(Ⅲ) and HAAP=3-{[2-(N-1-phenyl-2,3-dimethylpyrazol-3-in-5-on-4-yl)]hydrazone}pent-2,3,4-trione. The ligand and metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, infrared, far infrared and proton NMR spectral data. The spectral data revealed that the ligand existed in the hydrazo form and coordinated to the metal ion without deprotonation in a neutral tridentate manner, through carbonyl oxygen of pyrazolone ring, hydrazo nitrogen and carbonyl oxygen of the acetylace-tone moiety. The molar conductance values adequately supported their non-electrolytic nature. The ligand and the praseodymium(Ⅲ) complex were subjected to X-ray diffraction studies. Thermal decomposition behavior of the lanthanum(Ⅲ) complex was also examined.