Lanthanum complex (phenH)2[La(NO3)5(phen)]·CH3OH (1, phen=phenanthroline) was synthesized and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, s...Lanthanum complex (phenH)2[La(NO3)5(phen)]·CH3OH (1, phen=phenanthroline) was synthesized and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/c with a=20.3040(3), b=10.7091(1), c=19.0771(2), β=102.090(1)°, V=4056.07(8)3, Z=4, Dc=1.676 g/cm3, μ= 1.142 mm-1, F(000)=2056, the final R=0.0346 and wR=0.0793 for 9981 (Rint=0.0358) independent reflections. The mononuclear complex 1 consists of four parts: two phenH+ cations formed by the protonation of phen, one complex anion [La(NO3)5(phen)]2-, and one solvent methanol molecule. The complex anion contains one phen and five nitrate ligands which both chelate the center La(III) ion, adopting a distorted twelve-coordinated icosahedral geometry. The cations, anion and solvent molecule are linked together by hydrogen bonds. One of the protonated phenanthrolines (phenH+) acting as cation connects to the anion via N–H…O hydrogen bond directly, and the other one links to the anion through an intermediate solvent CH3OH via N–H…O and O–H…O hydrogen bonds. By the plentiful additional weak C–H…O intermolecular hydrogen bonds, the compound molecules construct a two-dimensional layer structure.展开更多
γ-La2S3 nanoparticles were successfully prepared by thermal decomposition of lanthanum complex La(Et2S2CN)3·phen at low temperature. The obtained sample was characterized by the X-ray powder diffraction (XRD...γ-La2S3 nanoparticles were successfully prepared by thermal decomposition of lanthanum complex La(Et2S2CN)3·phen at low temperature. The obtained sample was characterized by the X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and element analysis. The decomposition mechanism of lanthanum complex was studied by thermogravimetric analyses (TGA). The results showed that the obtained samples were cubic phase particles with uniform sizes among 10–30 nm and γ-La2S3 was prepared by decomposition of La(Et2S2CN)3·phen via La4(Et2S2CN)3 as an intermediate product. The band gap of γ-La2S3 was 2.97 eV, which was bigger than bulk crystal because of pronounced quantum confinement effect.展开更多
Complexes of the general formula,(Me_4N)_2[(Ln(HDPA)_2(DPA)]·Cl,have been synthesized,where Ln=La,Ce,Pr,Nd,Sm and H_2DPA=dipicolinic acid.Among them,the crystal structure of the La complex has been determined by ...Complexes of the general formula,(Me_4N)_2[(Ln(HDPA)_2(DPA)]·Cl,have been synthesized,where Ln=La,Ce,Pr,Nd,Sm and H_2DPA=dipicolinic acid.Among them,the crystal structure of the La complex has been determined by a four-circle X-ray diffractometer to a final R value of 0.080.The crystal is orthorhombic,space group Pccn with a=1.0321(1),b=1.4951(2),c=2.0766(6)nm,V=3.2044(9)nm^3,and Z=4.The rare earth ion is nine coordinated to forming a tortuous tricapped trigonal prism.展开更多
Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, mola...Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, molar conductance, infrared, electronic spectra, H-1 NMR, thermogravimetric and differential thermal analysis.展开更多
A novel complex of lanthanum ( Ⅲ ) with demethylcantharidate group (DCA), Na [ La (DCA) 2 (H2O) ], was synthesized in aqueous solution and characterized by elemental analysis, molar conductance, IR, UV, ^1H-N...A novel complex of lanthanum ( Ⅲ ) with demethylcantharidate group (DCA), Na [ La (DCA) 2 (H2O) ], was synthesized in aqueous solution and characterized by elemental analysis, molar conductance, IR, UV, ^1H-NMR spectra and TG-DTA. The results suggest that lanthanum ion is seven-coordinated. Six oxygen atoms are from carboxyl groups and cyclic ethers of two DCA ligand, and on oxygen is from a H2O. The antitumor activities of the complex against HL-60 human leukemia, BGC-823 human gastric carcinoma, Bel-7402 human hepatic carcinoma, Hela human cervical carcinoma were investigated with MT'F or SRB assays. Na[La(DCA)2(H2O)] exhibits stronger inhibition against certain kinds of cancer cells than Na2DCA in vitro.展开更多
The title complex was prepared from self-assembly reaction of La(NO3)3(6H2O, Zn(NO3)2(6H2O, m-cyanobenzoic acid (m-CNC6H4COOH) and pyridine (Py) in refluxing ethanol and its structure was determined by single-...The title complex was prepared from self-assembly reaction of La(NO3)3(6H2O, Zn(NO3)2(6H2O, m-cyanobenzoic acid (m-CNC6H4COOH) and pyridine (Py) in refluxing ethanol and its structure was determined by single-crystal X-ray diffraction. Crystallographic data: C94H62N12La2O22Zn2, Mr = 2120.12, triclinic space group P, a = 13.2219(5), b = 13.2713(5), c = 14.1987(6) ?, (???69.156(1), ( = 84.034(1), ( = 89.400(1) (, V = 2314.9(2) ?3, Z = 1, Dc = 1.521 g/cm3, F(000) = 1060, ( (MoK() = 14.94 cm-1, the final R = 0.043 and wR = 0.117 for 6381 unique reflections with I > 2((I). Crystal structure determination shows that the neighboring lanthanum(III) and zinc(II) ions are bridged by three bidentate m-cyanobenzonate ligands in the syn-syn fashion to form a pair of dinuclear [LaZn(m-CNC6H4COO)3(Py)(C2H5OH)] subunits, being linked together by two bidentate and two tridentate m-cyanobenzonate groups in the syn-syn and syn-anti modes, respectively, to construct a tetranuclear La-Zn complex [La2Zn2(m-CNC6H4COO)10(Py)2(C2H5OH)2].展开更多
A new lanthanum complex, (H3O)2[La(C7H3NO5)2(H2O)212.3(H2O) or (HaO)E[La(HChel)2(HEO)E]2.3(H2O) 1 (H3Chel = 4-hydroxypyridine-2,6-dicarboxylic(chelidamic) acid), has been prepared by the hydrotherm...A new lanthanum complex, (H3O)2[La(C7H3NO5)2(H2O)212.3(H2O) or (HaO)E[La(HChel)2(HEO)E]2.3(H2O) 1 (H3Chel = 4-hydroxypyridine-2,6-dicarboxylic(chelidamic) acid), has been prepared by the hydrothermal reaction, and its crystal structure was determined based on single-crystal diffraction data. Compound I crystallizes in triclinic, space group Pi with a = 9.6939(19), b = 10.176(2), c = 11.502(2)A, α = 111.52(3), β = 93.74(3), γ = 103.33(3)°, V = 1013.0(3)A3, Dc = 1.912 g/cm3, Z = 1, Mr = 1166.40, p = 2.188 mm-1, 2(MoKa) = 0.71073 A and F(000) = 574. The final R = 0.0342 and wR = 0.0737 for 4080 observed reflections with I 〉 2σ(I), and R = 0.0429 and wR = 0.0772 for all data. Compound 1 contains two lanthanum ions, four chelidamic acid ligands, four coordinated water molecules, two hydroniums, and three discrete water molecules. The LaⅢ atom is ten-coordinated by four oxygen and two nitrogen atoms from two tridentate chelating chelidamic acid ligands, two carboxylic oxygen atoms from an adjacent chelidamic acid ligand and two coordinated water molecules, leading to a distorted dodecahedral geometry. A three-dimensional network is formed by H-bonds.展开更多
ABSTRACT A new lanthanumm-ironm complex [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4]·H2O 1 (DMSO = dimethylsulfoxide) has been prepared by a facile approach, ball-milling method, and characterized by X-ray diffrac...ABSTRACT A new lanthanumm-ironm complex [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4]·H2O 1 (DMSO = dimethylsulfoxide) has been prepared by a facile approach, ball-milling method, and characterized by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 9.7125(3), b = 21.5336(7), c = 14.3804(5)A, β = 93.242(3)°, C16H34FeLaN60O7S5, Mr= 777.55, V = 3002.8(2)A^3, Z = 4, Dc = 1.720 g/cm^3, S = 1.053, μ(MoKα) = 2.278 mm^-1, F(000) = 1564, R = 0.0490 and ωR = 0.1270. The crystal structure analysis of 1 reveals a slightly distorted squareantiprism eighffold-coordinated La(Ⅲ) ion and a 1-D zigzag chain structure extending through the Fe-CN-La-NC-Fe linkages. The [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4] species are held together via hydrogen bonds to form a three-dimensional framework.展开更多
A new dinuclear La(Ⅲ) complex [La2(4-cba)4[H(4-cba)2]2(phen)2(H2O)4] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed...A new dinuclear La(Ⅲ) complex [La2(4-cba)4[H(4-cba)2]2(phen)2(H2O)4] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by singlecrystal X-ray diffraction. Crystallographic data: C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518(3), b = 17.033(6), c = 17.551(6)A, α = 115.333(4), β = 92.9910(10), γ = 99.366(5)°, V = 1985.3(12)A^3, Z = 1, Dc = 1.574 g/cm^3, F(000) = 944 μ = 1.145 mm^–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with Ⅰ 〉 2σ(I). In 1, two nine-coordinated La(Ⅲ) ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La(Ⅲ) ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.展开更多
A novel lanthanum(III) complex, [LaL2(NO3)3].H2O (1) based on L (L = N-(na- phthalene-l-yl)-2-(quinolin-8-yloxy)acetamide), was synthesized and characterized by X-ray diffraction. The crystal of I belongs ...A novel lanthanum(III) complex, [LaL2(NO3)3].H2O (1) based on L (L = N-(na- phthalene-l-yl)-2-(quinolin-8-yloxy)acetamide), was synthesized and characterized by X-ray diffraction. The crystal of I belongs to the monoclinic system, space group C2c with Mr= 1017.69, a = 25.1438(17), b = 13.5950(9), c = 18.2349(12) A, β= 132.4980(10)° V= 4595.8(5) A3, Z= 4, Dc = 1.471 Mg/m3, F(000) = 2056,μ= 1.004 mm-1, R = 0,0588 and wR = 0.1402. The central La(lI1) ion is coordinated to four oxygen atoms, two nitrogen atoms from two independent acetarnide ligands and six oxygen atoms from three nitrate anions, possessing a distorted icosahedron coordination geometry. In the crystal of 1, intermolecular N-H……O hydrogen bonds linked the molecules into chains along the c axis. In solid state and CH3CN solution, complex 1 exhibits stronger fluorescent emission than the ligand L.展开更多
A series of perovskite-type complex oxides LaNi1-xRuxO3 were prepared and studied by means of XRD. The effects of some factors on th complex oxides were discussed. Each kind of those perovskite-type complex oxides was...A series of perovskite-type complex oxides LaNi1-xRuxO3 were prepared and studied by means of XRD. The effects of some factors on th complex oxides were discussed. Each kind of those perovskite-type complex oxides was used to prepare cathode by composite-electroplating technique. The cathodes were electrochemically charactrized. The results show that these novel cathode exhibit high activities and excellent stabilities during long-term continuous electrolysis with some current interruptions.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
A novel metal-organic complex [La(o-NCP)3]n (o-HNCP = 2-(2-carboxyphen- yl)imidazo(4,5- f)(1,10)-phenanthroline) has been hydrothermally synthesized and characterized by elemental analysis, infrared analysis...A novel metal-organic complex [La(o-NCP)3]n (o-HNCP = 2-(2-carboxyphen- yl)imidazo(4,5- f)(1,10)-phenanthroline) has been hydrothermally synthesized and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The complex crystallizes in triclinic, space group P1 with a = 9.898(2), b = 16.193(3), c = 16.909(3) A, a = 67.68(3), β = 80.85(3), y = 78.78(3)°, V= 2448.2(8) A3, Z = 2, Mr = 1156.9, Dc = 1.569 g/cm3,μ = 0.71073 A, F(000) = 1164, GOOF = 1.065, the final R = 0.051 and wR = 0.123 for 8539 observed reflections with I 〉 2o(I). The complex exhibits a one-dimensional double chain structure. The adjacent chains are further connected by N-H...N hydrogen bonds which help to form a two-dimensional suprarnolecular architecture. Furthermore, the complex exhibits excellent thermal stability and luminescent property.展开更多
The bimetallic ternary complex formation in the aqueous solution of La and Cu with alizarin fluorine blue (AFB) was studied by spectrophotometry.The ternary complex LaCu3(AFB)3 has maximum light absorption at 550nm.Th...The bimetallic ternary complex formation in the aqueous solution of La and Cu with alizarin fluorine blue (AFB) was studied by spectrophotometry.The ternary complex LaCu3(AFB)3 has maximum light absorption at 550nm.The colour reaction selectivity is fairly good and the method can be applied to the direct photometric determination of copper in lanthanum or some pure metals.A new mathematical approach to the treatment of spectrophotometric data for differentiation between mononuclear and polynuclear in solution is presented.The improvable fixed logarithm method is for complexes of the type MmBn(m=n) or MmBn(m=n).We report that La(Ⅲ) combines with AFB at pH 4.5 to form a single complex,withm=n=2,La2(AFB)2.展开更多
Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized an...Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized and the calculation results show that the lanthanum ion is coordinated by one nitrogen atom and three oxygen atoms of L^1 and two oxygen atoms of nitrate ion. The bond length of La-N is 0.2637 nm and the average length of La-O is 0.2526 nm, which are consistent with the literatures. In addition, the stabilities, electronic structural characteristics and IR spectra of the complex have been analyzed, which describe the coordination of lanthanum ion with other atoms in detail.展开更多
A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 ...A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 5660(3) nm, c =1 3512(3) nm, α=90 00°, β=94 39(1)°, γ=90 00°, V =3 6037(12) nm 3, Z =4 . The complex is a ten-coordinated one with a lanthanum ion surrounded by a N 4O 6 set. The crystal structure is stabilized by hydrogen bonds between water molecules and NO - 3 anions.展开更多
The complex of [La 2(P MBA) 6(PHEN) 2]2H 2O (P MBA: p methylbenzoate and PHEN: 1,10 phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [La 2(P M...The complex of [La 2(P MBA) 6(PHEN) 2]2H 2O (P MBA: p methylbenzoate and PHEN: 1,10 phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [La 2(P MBA) 6(PHEN) 2]2H 2O in dynamic nitrogen atmosphere was investigated by TG DTG techniques. The results show that the thermal decomposition process of the [La 2(P MBA) 6(PHEN) 2]2H 2O occurs in five steps. The empirical kinetic model for the first step thermal decomposition obtained by Malek method is SB(m,n). The activation energy E and the pre exponential factor lnA for this step reaction are 76.4 kJ·mol -1 and 24.92, respectively.展开更多
The complex of lanthanum chloride with Glycine and Alanine,La(Gly)2(Ala)3Cl3·2H2O,was synthesized and characterized by IR,elementary analysis,thermogravimetric analysis,and chemical analysis.The dissolution e...The complex of lanthanum chloride with Glycine and Alanine,La(Gly)2(Ala)3Cl3·2H2O,was synthesized and characterized by IR,elementary analysis,thermogravimetric analysis,and chemical analysis.The dissolution enthalpies of LaCl3 ·7H2O(s),2Gly(s)+ 3Ala(s)and La(Gly)2(Ala)3Cl3 ·2H2O(s)were determined in 2 mol·L-1 HCl by a solution-reaction isoperibol calorimeter.By designing a thermochemical cycle in terms of Hess' Law and through calculation,the reaction enthalpy of lanthanum chloride seven-hydrate with Glycine and Alanine was obtained:ΔrHθm(298.15 K)=(29.652±0.504)kJ·mol-1,and the standard enthalpy of formation of La(Gly)2(Ala)3Cl3·2H2O(s)ΔfHθm [La(Gly)2(Ala)3Cl3·2H2O,s,298.15 K]=-4467.6±8.3 kJ·mol-1.展开更多
A new complex of lanthanum orotate [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was synthesized using a hydrothermal method. The crystal structure was determined with help of single crystal X-ray diff...A new complex of lanthanum orotate [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was synthesized using a hydrothermal method. The crystal structure was determined with help of single crystal X-ray diffraction analysis. The complex crystallized in orthorhombic system, Cmc2(1) space group. In the complex, the center lanthanum (Ⅲ) ion was nine-coordinated with coordination geometry of a distorted monocapped square antiprism, in which two of the nine coordinated oxygen atoms were from two orotate ligands in a monodentate mode, one oxygen atom from a hydroxyl, and the others from six coordinated water molecules. The mononuclear complex [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was linked through the hydrogen bonds into an infinite supermolecular honeycomb structure.展开更多
A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was charact...A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806(7) nm, b=1.10258(5) nm, c=1.60333(8) nm and β=101.9400(10)°. The complex was polymeric with La^III atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaIn atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types of O-H…O, N-H…O and C-H…O) and ion pairing interactions connected the various components into a supramolecular structure.展开更多
基金supported by the Scientific Research Common Program of Beijing Municipal Commission of Education (KM201010028008)
文摘Lanthanum complex (phenH)2[La(NO3)5(phen)]·CH3OH (1, phen=phenanthroline) was synthesized and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/c with a=20.3040(3), b=10.7091(1), c=19.0771(2), β=102.090(1)°, V=4056.07(8)3, Z=4, Dc=1.676 g/cm3, μ= 1.142 mm-1, F(000)=2056, the final R=0.0346 and wR=0.0793 for 9981 (Rint=0.0358) independent reflections. The mononuclear complex 1 consists of four parts: two phenH+ cations formed by the protonation of phen, one complex anion [La(NO3)5(phen)]2-, and one solvent methanol molecule. The complex anion contains one phen and five nitrate ligands which both chelate the center La(III) ion, adopting a distorted twelve-coordinated icosahedral geometry. The cations, anion and solvent molecule are linked together by hydrogen bonds. One of the protonated phenanthrolines (phenH+) acting as cation connects to the anion via N–H…O hydrogen bond directly, and the other one links to the anion through an intermediate solvent CH3OH via N–H…O and O–H…O hydrogen bonds. By the plentiful additional weak C–H…O intermolecular hydrogen bonds, the compound molecules construct a two-dimensional layer structure.
基金supported by the National High Technology Research and Development Program of China (863 Program) (2009AA03Z431)
文摘γ-La2S3 nanoparticles were successfully prepared by thermal decomposition of lanthanum complex La(Et2S2CN)3·phen at low temperature. The obtained sample was characterized by the X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and element analysis. The decomposition mechanism of lanthanum complex was studied by thermogravimetric analyses (TGA). The results showed that the obtained samples were cubic phase particles with uniform sizes among 10–30 nm and γ-La2S3 was prepared by decomposition of La(Et2S2CN)3·phen via La4(Et2S2CN)3 as an intermediate product. The band gap of γ-La2S3 was 2.97 eV, which was bigger than bulk crystal because of pronounced quantum confinement effect.
基金Project supported by the National Natural Science Foundation of China
文摘Complexes of the general formula,(Me_4N)_2[(Ln(HDPA)_2(DPA)]·Cl,have been synthesized,where Ln=La,Ce,Pr,Nd,Sm and H_2DPA=dipicolinic acid.Among them,the crystal structure of the La complex has been determined by a four-circle X-ray diffractometer to a final R value of 0.080.The crystal is orthorhombic,space group Pccn with a=1.0321(1),b=1.4951(2),c=2.0766(6)nm,V=3.2044(9)nm^3,and Z=4.The rare earth ion is nine coordinated to forming a tortuous tricapped trigonal prism.
文摘Six new complexes of lanthanum with amino acid Schiff base ligands, A-F, were prepared in methanol-aqueous solution. The composition and properties of the title complexes were characterized by elemental analysis, molar conductance, infrared, electronic spectra, H-1 NMR, thermogravimetric and differential thermal analysis.
文摘A novel complex of lanthanum ( Ⅲ ) with demethylcantharidate group (DCA), Na [ La (DCA) 2 (H2O) ], was synthesized in aqueous solution and characterized by elemental analysis, molar conductance, IR, UV, ^1H-NMR spectra and TG-DTA. The results suggest that lanthanum ion is seven-coordinated. Six oxygen atoms are from carboxyl groups and cyclic ethers of two DCA ligand, and on oxygen is from a H2O. The antitumor activities of the complex against HL-60 human leukemia, BGC-823 human gastric carcinoma, Bel-7402 human hepatic carcinoma, Hela human cervical carcinoma were investigated with MT'F or SRB assays. Na[La(DCA)2(H2O)] exhibits stronger inhibition against certain kinds of cancer cells than Na2DCA in vitro.
基金the Natural Science Foundation of China, Fujian Province and Chinese Academy of Sciences.
文摘The title complex was prepared from self-assembly reaction of La(NO3)3(6H2O, Zn(NO3)2(6H2O, m-cyanobenzoic acid (m-CNC6H4COOH) and pyridine (Py) in refluxing ethanol and its structure was determined by single-crystal X-ray diffraction. Crystallographic data: C94H62N12La2O22Zn2, Mr = 2120.12, triclinic space group P, a = 13.2219(5), b = 13.2713(5), c = 14.1987(6) ?, (???69.156(1), ( = 84.034(1), ( = 89.400(1) (, V = 2314.9(2) ?3, Z = 1, Dc = 1.521 g/cm3, F(000) = 1060, ( (MoK() = 14.94 cm-1, the final R = 0.043 and wR = 0.117 for 6381 unique reflections with I > 2((I). Crystal structure determination shows that the neighboring lanthanum(III) and zinc(II) ions are bridged by three bidentate m-cyanobenzonate ligands in the syn-syn fashion to form a pair of dinuclear [LaZn(m-CNC6H4COO)3(Py)(C2H5OH)] subunits, being linked together by two bidentate and two tridentate m-cyanobenzonate groups in the syn-syn and syn-anti modes, respectively, to construct a tetranuclear La-Zn complex [La2Zn2(m-CNC6H4COO)10(Py)2(C2H5OH)2].
基金Supported by the Nanchang Hangkong University Doctoral Foundation (EA200702136)
文摘A new lanthanum complex, (H3O)2[La(C7H3NO5)2(H2O)212.3(H2O) or (HaO)E[La(HChel)2(HEO)E]2.3(H2O) 1 (H3Chel = 4-hydroxypyridine-2,6-dicarboxylic(chelidamic) acid), has been prepared by the hydrothermal reaction, and its crystal structure was determined based on single-crystal diffraction data. Compound I crystallizes in triclinic, space group Pi with a = 9.6939(19), b = 10.176(2), c = 11.502(2)A, α = 111.52(3), β = 93.74(3), γ = 103.33(3)°, V = 1013.0(3)A3, Dc = 1.912 g/cm3, Z = 1, Mr = 1166.40, p = 2.188 mm-1, 2(MoKa) = 0.71073 A and F(000) = 574. The final R = 0.0342 and wR = 0.0737 for 4080 observed reflections with I 〉 2σ(I), and R = 0.0429 and wR = 0.0772 for all data. Compound 1 contains two lanthanum ions, four chelidamic acid ligands, four coordinated water molecules, two hydroniums, and three discrete water molecules. The LaⅢ atom is ten-coordinated by four oxygen and two nitrogen atoms from two tridentate chelating chelidamic acid ligands, two carboxylic oxygen atoms from an adjacent chelidamic acid ligand and two coordinated water molecules, leading to a distorted dodecahedral geometry. A three-dimensional network is formed by H-bonds.
基金the NNSFC (20571075, 20521101)the NSF for Distinguished Young Scientist of China (20425104)the NSF of Fujian Province (E0510028)
文摘ABSTRACT A new lanthanumm-ironm complex [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4]·H2O 1 (DMSO = dimethylsulfoxide) has been prepared by a facile approach, ball-milling method, and characterized by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 9.7125(3), b = 21.5336(7), c = 14.3804(5)A, β = 93.242(3)°, C16H34FeLaN60O7S5, Mr= 777.55, V = 3002.8(2)A^3, Z = 4, Dc = 1.720 g/cm^3, S = 1.053, μ(MoKα) = 2.278 mm^-1, F(000) = 1564, R = 0.0490 and ωR = 0.1270. The crystal structure analysis of 1 reveals a slightly distorted squareantiprism eighffold-coordinated La(Ⅲ) ion and a 1-D zigzag chain structure extending through the Fe-CN-La-NC-Fe linkages. The [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4] species are held together via hydrogen bonds to form a three-dimensional framework.
基金This work was supported by the National Natural Science Foundation of China (20671091)Natural Science Foundation of Fujian Province (A0420002 and 2005I017)
文摘A new dinuclear La(Ⅲ) complex [La2(4-cba)4[H(4-cba)2]2(phen)2(H2O)4] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by singlecrystal X-ray diffraction. Crystallographic data: C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518(3), b = 17.033(6), c = 17.551(6)A, α = 115.333(4), β = 92.9910(10), γ = 99.366(5)°, V = 1985.3(12)A^3, Z = 1, Dc = 1.574 g/cm^3, F(000) = 944 μ = 1.145 mm^–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with Ⅰ 〉 2σ(I). In 1, two nine-coordinated La(Ⅲ) ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La(Ⅲ) ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.
基金supported by the National Natural Science Foundation of China(21001040)Education Department of Henan Province(No.12B150011 and 14B150029)
文摘A novel lanthanum(III) complex, [LaL2(NO3)3].H2O (1) based on L (L = N-(na- phthalene-l-yl)-2-(quinolin-8-yloxy)acetamide), was synthesized and characterized by X-ray diffraction. The crystal of I belongs to the monoclinic system, space group C2c with Mr= 1017.69, a = 25.1438(17), b = 13.5950(9), c = 18.2349(12) A, β= 132.4980(10)° V= 4595.8(5) A3, Z= 4, Dc = 1.471 Mg/m3, F(000) = 2056,μ= 1.004 mm-1, R = 0,0588 and wR = 0.1402. The central La(lI1) ion is coordinated to four oxygen atoms, two nitrogen atoms from two independent acetarnide ligands and six oxygen atoms from three nitrate anions, possessing a distorted icosahedron coordination geometry. In the crystal of 1, intermolecular N-H……O hydrogen bonds linked the molecules into chains along the c axis. In solid state and CH3CN solution, complex 1 exhibits stronger fluorescent emission than the ligand L.
文摘A series of perovskite-type complex oxides LaNi1-xRuxO3 were prepared and studied by means of XRD. The effects of some factors on th complex oxides were discussed. Each kind of those perovskite-type complex oxides was used to prepare cathode by composite-electroplating technique. The cathodes were electrochemically charactrized. The results show that these novel cathode exhibit high activities and excellent stabilities during long-term continuous electrolysis with some current interruptions.
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.
基金Supported by the Program for New Century Excellent Talents in University(NCET-10-0176)
文摘A novel metal-organic complex [La(o-NCP)3]n (o-HNCP = 2-(2-carboxyphen- yl)imidazo(4,5- f)(1,10)-phenanthroline) has been hydrothermally synthesized and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The complex crystallizes in triclinic, space group P1 with a = 9.898(2), b = 16.193(3), c = 16.909(3) A, a = 67.68(3), β = 80.85(3), y = 78.78(3)°, V= 2448.2(8) A3, Z = 2, Mr = 1156.9, Dc = 1.569 g/cm3,μ = 0.71073 A, F(000) = 1164, GOOF = 1.065, the final R = 0.051 and wR = 0.123 for 8539 observed reflections with I 〉 2o(I). The complex exhibits a one-dimensional double chain structure. The adjacent chains are further connected by N-H...N hydrogen bonds which help to form a two-dimensional suprarnolecular architecture. Furthermore, the complex exhibits excellent thermal stability and luminescent property.
文摘The bimetallic ternary complex formation in the aqueous solution of La and Cu with alizarin fluorine blue (AFB) was studied by spectrophotometry.The ternary complex LaCu3(AFB)3 has maximum light absorption at 550nm.The colour reaction selectivity is fairly good and the method can be applied to the direct photometric determination of copper in lanthanum or some pure metals.A new mathematical approach to the treatment of spectrophotometric data for differentiation between mononuclear and polynuclear in solution is presented.The improvable fixed logarithm method is for complexes of the type MmBn(m=n) or MmBn(m=n).We report that La(Ⅲ) combines with AFB at pH 4.5 to form a single complex,withm=n=2,La2(AFB)2.
基金This work was supported by the National Natural Science Foundation of China (20203011)
文摘Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized and the calculation results show that the lanthanum ion is coordinated by one nitrogen atom and three oxygen atoms of L^1 and two oxygen atoms of nitrate ion. The bond length of La-N is 0.2637 nm and the average length of La-O is 0.2526 nm, which are consistent with the literatures. In addition, the stabilities, electronic structural characteristics and IR spectra of the complex have been analyzed, which describe the coordination of lanthanum ion with other atoms in detail.
基金Supported by the National Natural Science Foundation of China( No. 2 98710 14 ) and the Foundation of Doctor byL anzhou U niversit
文摘A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 5660(3) nm, c =1 3512(3) nm, α=90 00°, β=94 39(1)°, γ=90 00°, V =3 6037(12) nm 3, Z =4 . The complex is a ten-coordinated one with a lanthanum ion surrounded by a N 4O 6 set. The crystal structure is stabilized by hydrogen bonds between water molecules and NO - 3 anions.
文摘The complex of [La 2(P MBA) 6(PHEN) 2]2H 2O (P MBA: p methylbenzoate and PHEN: 1,10 phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [La 2(P MBA) 6(PHEN) 2]2H 2O in dynamic nitrogen atmosphere was investigated by TG DTG techniques. The results show that the thermal decomposition process of the [La 2(P MBA) 6(PHEN) 2]2H 2O occurs in five steps. The empirical kinetic model for the first step thermal decomposition obtained by Malek method is SB(m,n). The activation energy E and the pre exponential factor lnA for this step reaction are 76.4 kJ·mol -1 and 24.92, respectively.
基金Project supported by the Hunan Provincial Natural Sciences Foundation of China(03JJY3019)the Hunan Provincial Educational Ministry Foundation of China(05C627)
文摘The complex of lanthanum chloride with Glycine and Alanine,La(Gly)2(Ala)3Cl3·2H2O,was synthesized and characterized by IR,elementary analysis,thermogravimetric analysis,and chemical analysis.The dissolution enthalpies of LaCl3 ·7H2O(s),2Gly(s)+ 3Ala(s)and La(Gly)2(Ala)3Cl3 ·2H2O(s)were determined in 2 mol·L-1 HCl by a solution-reaction isoperibol calorimeter.By designing a thermochemical cycle in terms of Hess' Law and through calculation,the reaction enthalpy of lanthanum chloride seven-hydrate with Glycine and Alanine was obtained:ΔrHθm(298.15 K)=(29.652±0.504)kJ·mol-1,and the standard enthalpy of formation of La(Gly)2(Ala)3Cl3·2H2O(s)ΔfHθm [La(Gly)2(Ala)3Cl3·2H2O,s,298.15 K]=-4467.6±8.3 kJ·mol-1.
基金Project supported by the Natural Science Foundation of Beijing (2073022)the Science and Technology Program, BeijingMunicipal Education Commission (KM200510028007)
文摘A new complex of lanthanum orotate [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was synthesized using a hydrothermal method. The crystal structure was determined with help of single crystal X-ray diffraction analysis. The complex crystallized in orthorhombic system, Cmc2(1) space group. In the complex, the center lanthanum (Ⅲ) ion was nine-coordinated with coordination geometry of a distorted monocapped square antiprism, in which two of the nine coordinated oxygen atoms were from two orotate ligands in a monodentate mode, one oxygen atom from a hydroxyl, and the others from six coordinated water molecules. The mononuclear complex [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was linked through the hydrogen bonds into an infinite supermolecular honeycomb structure.
文摘A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806(7) nm, b=1.10258(5) nm, c=1.60333(8) nm and β=101.9400(10)°. The complex was polymeric with La^III atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaIn atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types of O-H…O, N-H…O and C-H…O) and ion pairing interactions connected the various components into a supramolecular structure.