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Synthesis and crystal Structure of Binuclear Ytterbium complex with Isonicotinoyl Hydrazone

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Journal of rare earths 2001年第2期19卷 86-89页

作者：卜显和鹿守亮陈巍张若桦 Nankai Univ Dept Chem Tianjin 300071 Peoples R China Peking Univ State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China

The ytterbium complex of isonicotinoyl hydrazone was synthesized and the structure was determined by X-ray diffraction analysis. The crystal and molecular structure of the title complex [Yb-2(L)(3)](OH)(3) shows that the complex has two identical nine-coordinated ytterbium ions with each surrounded by N3O6 donor set, Two ytterbium ions are bridged by three phenolate oxygen atoms, The geometry around each ytterbium ions can be considered as a three-capped trigonal prism.

关键词： rare earths synthesis ytterbium complex isonicotinoyl hydrazone crystal structure

Irreversible colossal Magnetoresistance in La_(0.58)Dy_(0.09)ca_(0.33)MnO_3

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Journal of mat.rials Science & Technology 2003年第6期19卷 622-624页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Youyong DAI, chengjian WANG, Xiaobo YUAN and Liangmo MEIDepartment of Physics and state key lab.ratory of crystal mat.rials, Shandong University, Ji’nan 250100, china lab. of crystal mat. Dept. of Phys. Shandong Univ. Ji'nan 250100 China

The representative sample La0.58Dy0.09ca0.33MnO3 of Dy doped La0.67ca0.33MnO3 rare-earth manganites was investigated. The most important effect of Dy doping is to introduce the magnetoimpurity and form the spin clusters which induce dramat.cally large cMR in La0.58Dy0.09ca0.33MnO3. The fitting results of field-induced resistivity decrease to the Brillouin function indicate that the cMR is caused by the spin dependent hopping between spin clusters. It is the magnetic field that reduces the size of spin clusters and induces a field-induced irreversible cMR behaviour.

关键词： Spin cluster Magnetoimpurity colossal magnetoresistance

crystal　Structure　and　Specific　Rotation　of　a　Tetrakis－HistidineOcto－Aquo　Di－Erbium　Perchlorate　complex

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Journal of rare earths 1996年第2期14卷 94-97页

作者：杨维春陈德福金天柱章士伟 BEIJING UNIV STATE KEY LAB RARE EARTH MAT CHEM & APPLICATBEIJING 100871PEOPLES R CHINA BEIJING UNIV INST PHYS CHEMBEIJING 100871PEOPLES R CHINA

The title complex [Er_2 (His·H￣+)_4 (H_2O)_8] (clO_4)_(10)·4H_2O was synthesized in aqueous solution and its crystal structure was determined by X ray diffraction method. The crystal is triclinic, space group P1 with a=1.1726(2) nm, b=1.2660(3) nm, c=1.3142(3) nm, a=82. 92(3)°,β=70. 86(3)°, γ=83.06(3)°, V=1. 8223(7) nm￣3, Z=1, Dc=1.977g/cm￣3. The complex was a binuclear molecule, and each erbium ion is coordinated by four carboxylic oxygen atoms from four histidine and four oxygen atoms from H_2O, forming a coordination polyhedron of square antiprism. The structure analysis and specific rotation determination shows that the crystal contains enantiomers.

关键词： Erbium complex crystal structure Histidine

Strategies to advance thermoelectric performance of PbSe and PbS mat.rials

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rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian Qiu-Juan cui Shu-Fang Wang Li-Dong Zhao Shijiazhuang key lab.ratory of Low carbon Energy mat.rials College of Chemical EngineeringShijiazhuang UniversityShijiazhuang 050035China Hebei key lab.of Optic-Electronic Informat.on and mat.rials College of Physics Science and TechnologyHebei UniversityBaoding 071002China School of mat.rials Science and Engineering Beihang UniversityBeijing 100191China

Thermoelectric mat.rials possess the unique capability to convert thermal energy into electric energy and vice versa,making them promising for waste heat recovery and efficient cooling ***,extensively investigated thermoelectric mat.rials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***,the broad application of these thermoelectric mat.rials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's *** the past few years,researchers have shown increasing interest in PbSe-and PbS-based mat.rials,primarily attributed to their abundant elemental supply and relatively low *** assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric *** strategies include optimizing carrier concentration(aliovalent doping,dynamic doping and defect state),enhancing density-of-state effective mass(band convergence,band flattening and energy filtering effect),optimizing carrier mobility(band sharpening and band alignment)and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing).This systemat.c summary and analysis provide novel insights and perspectives for the development of thermoelectric mat.rials.

关键词： PbSe and PbS thermoelectric mat.rials carrier concentration Density-of-state effective mass carrier mobility Lattice thermal conductivity

Minimum amount of extracting solvent of AB/Bc countercurrent extraction separation using organic feed

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Journal of rare earths 2014年第5期32卷 439-444页

作者：程福祥吴声张玻刘艳王嵩龄廖春生严纯华 china Minmetals (Beijing) Research Institute of RE co. Ltd Beijing National lab.ratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Lab on Rare Earth Materials and Bioinorganic Chemistry Peking University

For an AB/Bc countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent （Smin） and minimum amount of scrubbing agent solution （Wmin） were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/Bc separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/c pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic.a.d the aqueous phase at steady state were given by computer simulation.

关键词： rare earths countercurrent extraction hyperlink process 3-component separation

Orientational Isomerism and Its Reactivity of a Main Group Sandwich Anion[Ge_(9)-In-Ge_(9)]^(5-)

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chinese Journal of chemistry 2023年第19期41卷 2432-2438页

作者： Hong-Lei Xu Lei Qiao Zhong Ming Sun state key lab.ratory of Elemento-Organic chemistry Tianjin Key Lab of Rare Earth Materials and ApplicationsSchool of Material Science and EngineeringNankai UniversityTianjin 300350China

Two isomers of a sandwich-type anion [Ge_(9)-In-Ge_(9)]^(5–) were synthesized by controlling the chelating agents (2,2,2-crypt/18-c-6). Further reactions with early/late transition metal complexes, Mo(cO)_(6) and Ni(cOD)_(2), respectively, yielded two new types of inorganic sandwich derivatives: a half-sandwich cluster [Ge_(9)-In-Mo(cO)_(5)]^(3–) with a low-valence In(I) center and an unsymmetrical sandwich-type cluster {[(Ni@Ge_(9))In(Ni_(0.648)@Ge_(9))]}^(5–) due to the insertion of Ni atoms, respectively. The isolation of these new derivatives demonstrates the reactivity of sandwich-type [Ge_(9)-In-Ge_(9)]^(5–) acting as the precursor, which provides some enlightenment for constructing new inorganic sandwich compounds.

关键词： Sandwich complex cluster compounds Main group elements Germanium Indium

Effect of Substrate Temperature on Electroluminescence of SrS∶HoF_3 Thin Film

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rare Metals 1999年第1期18卷 12-16页

作者：赵丽娟赵国柱范希武李长华林建华 chinese Acad Sci Changchun Inst Phys Lab Excited State Proc Changchun 130021 Peoples R China Beijing Univ State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China

The SrS∶HoF 3 Electroluminescent (EL) thin films are prepared at the different substrate temperature by electron beam evaporation. The crystallinity and EL c.a.acteristics of the samples are analyzed. It is found that the main diffraction peak is (200) at the higher substrate temperature and the main diffraction peak is (111) at the lower substrate temperature. The blue emission intensity and EL brightness of the SrS∶HoF 3 thin films increase with the increase of the substrate temperature. Annealing the samples can c.a.ge the cyrstal phase and strengthen the blue emission of EL thin film.

关键词： Electroluminescence Substrate temperature SrS∶HoF 3 EL thin film.

NATURAL　BOND　ORBITAL　ANALYSIS　OF　RED　ROUSSINATE　AND　BLAcK　ROUSSINATE

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chinese chemical Letters 1996年第5期7卷 467-470页

作者： chen, ZD Yi, XH Kong, XL Li, LM Lu, JX BEIJING UNIV DEPT CHEM STATE KEY LAB RARE EARTH MAT CHEM & APPLICAT BEIJING 100871 PEOPLES R CHINA cHINESE AcAD ScI FUJIAN INST RES STRUCT MATTER STATE KEY LAB STRUCT CHEM FUZHOU 350002 PEOPLES R CHINA

Abstracts: In the purpose of study on the electronic structure feature for the activation center of the FeMo-cofactor of the nitrogenase as well as activation process of a dinitrogen molecule. the black Roussinate with an Fe4S3 cluster core is regarded as the first modeling complex .In this paper, natural bond orbitals for the cluster anions of the black Roussinate and the related redRoussinate are calculated on the basis of the first-order density mat.ixes obtained by the use of DV-Xα Scc method, leading to reasonable bonding patterns.

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Synthesis, c.a.acterization and Properties of Lanthanide Nitrate complexes with Isonicotinoyl Hydrazone

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Journal of rare earths 2001年第1期19卷 70-73页

作者：卜显和高育新陈巍刘河张若桦 Nankai Univ Dept Chem Tianjin 300071 Peoples R China Peking Univ State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China

Some light-lanthanide nitrate complexes were obtained by the reaction of lanthanide nitrate with isonicotinoyl hydrazone (HL = N,N'-diisonicotinoyl-2-hydroxy-5-methyl-isophthalaldehyde dihydrazone) in methanol. The general formula of the complexes is Ln(L) (NO3)(2) . nH(2)O(Ln = La, ce, Pr, Nd and Sm; n = 0, 1). The complexes were c.a.acterized by elemental analyses, conduc.a.ce, thermal analyses, UV and IR spectra. The results show that the lanthanide ion in each complex is coordinated by oxygen and nitrogen atoms of the ligand (L) and the oxygen atoms of the nitrate. The amide-oxygen atoms of L coordinate to the Ln ions in its keto-form. The magnetic susceptibility of the neodymium complex shows that the magnetic data obey curie-Weiss law in the range of 75K < T < 300K.

关键词： rare earths lanthanide complexes isonicotinoyl hydrazone synthesis c.a.acterization