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1.
A.I. Baranov L. Kloo R.A. Lunin B.A. Popovkin 《Journal of solid state chemistry》2004,177(10):3616-3625
A systematic search for mixed low-valence, nickel-tin chalcogenides performed by establishing phase relations in the parts of Ni-Sn-Se and Ni-Sn-Te ternary systems resulted in the discovery of two new compounds, Ni5.62SnSe2 and Ni5.78SnTe2. Single crystals of both compounds were prepared by chemical transport with iodine and crystal structures were determined by single crystal X-ray investigation. The ED patterns for Ni5.78SnTe2 showed the presence of satellite reflections, which indicate a modulated structure with q≈0.4a*. Average crystal structures of both compounds were determined to be of tetragonal symmetry (Sp.gr. I4/mmm, Z=2) with a=3.6890(8) Å, c=18.648(3) Å, Rw=0.0716 and a=3.7680(5) Å, c=19.419(4) Å, Rw=0.0832, correspondingly, and are isostructural to known Ni5.72SbSe2 and Ni5.66SbTe2. Measurements were carried out for both compounds with respect to thermal, electrical and magnetic properties. Ab initio band structure calculations were also performed to take a first glance into the electronic structure of such type compounds. The anisotropy of their band structure was found. Physical property measurements showed both compounds to be the anisotropic metallic conductors and paramagnetics. Calculated difference charge density maps revealed pairwise covalent and multicenter metallic nature of the d-metal—chalcogen and d-metal—p-metal interactions, respectively. 相似文献
2.
3.
A series of heterometallic LnIII–SbIII edta‐containing compounds with the formulas [Sb2(edta)2Ln]NO3 · nH2O [edta = ethylenediaminetetraacetate; Ln = Eu, n = 7 ( 1 ); Gd, n = 7.5 ( 2 ) and Tb, n = 8 ( 3 )] were synthesized and characterized by elemental analyses (EA), powder X‐ray diffraction (PXDP), Fourier transform infrared spectroscopy (FT‐IR), and thermogravimetric analyses (TGA). Their fluorescence and magnetic properties were also studied. The thermal analysis demonstrates the compounds formation of the antimony, lanthanide ions, and edta4– ligands. FT‐IR spectra reveal that the antimony and lanthanide ions are connected through the carboxylate bridges. The studies of luminescence properties show that compounds 1 and 3 exhibit typical luminescence in the visible region. Furthermore, magnetic properties reveal compounds 2 and 3 have weak ferromagnetic behavior. 相似文献
4.
《印度化学会志》2021,98(8):100097
Two rare hetero-metallic calcium(II)-zinc(II) complexes [CaZn4(OBz)10(μ2-hmt)2]n (1) and [Ca2Zn4(OBz)12(μ2-hmt)2]n (2) have been synthesized using basic zinc carbonate, benzoic acid (HOBz), hydrated calcium chloride and hexamethylenetetramine (hmt) by varying the molar ratio of the reactants. Both the complexes have been analyzed by elemental analysis, IR spectroscopy and X-ray crystallography. The complex 1 is a 1D polymer which contains one calcium ion and four zinc atoms in the asymmetric unit together with ten benzoates and two hmts. The polymer has been constructed by the alternate joining of paddle-wheel Zn2(OBz)4 units and Zn2Ca trinuclear species by μ2-hmt bridging molecules connecting Zn2+ ions. Zinc atoms have five coordinate square pyramidal geometries and four coordinate tetrahedral geometries in Zn2(OBz)4 and Zn2Ca moieties, respectively, whereas calcium atoms have six-coordinate distorted octahedral geometry. Complex 2 is also a 1D polymer but unlike complex 1, it contains four independent zinc and two independent calcium atoms in the asymmetric unit together with twelve benzoates and two hmts. By contrast, the polymeric structure of complex 2 has been formed by the connection of Zn2Ca trinuclear species via μ2 hmt bridging molecules at Zn centers. Complex 2 is also a 1D polymer but unlike complex 1, it contains four independent zinc and three independent calcium atoms in the asymmetric unit together with twelve benzoates and two hmts. All four zinc atoms are four coordinate with tetrahedral environments and the calcium atoms are six coordinated (two are located on a center of symmetry) exhibiting a distorted octahedral geometry. 相似文献
5.
Meng-Yue Jiang Li Yu Yi-Cheng Zhou Jing Jia Xue-Jian Si Wen-Wen Dong Zheng-Fang Tian Jun Zhao Dong-Sheng Li 《无机化学与普通化学杂志》2020,646(5):268-274
A novel three-dimensional (3D) d-f heterometallic metal-organic framework (MOF) formulated as [EuCd1.5L2(H2O)3] · 2H2O ( 1 ) [H3L = 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid] was successfully synthesized and characterized. Structural analysis displays that 1 features a 3D (3, 12)-connected framework constructed by [Eu2Cd3(tetrazole)4(COO)8] units. The powder X-ray diffraction measurement of 1 immersed in different solvents reveals that 1 possess good solvent stability. It is worth noting that 1 displays highly selective detection for ronidazole (RDZ) and 4-nitrophenol (4-NP) through luminescence quenching. The possible mechanism of luminescent sensing is also well discussed. 相似文献
6.
Frank W. Vergeer Taasje Mahabiersing Enrique Lozano Diz Georg Süss-Fink František Hartl 《Journal of Cluster Science》2004,15(1):47-59
Electrochemical and photochemical properties of the tetrahedral cluster [Ru3Ir(
3-H)(CO)13] were studied in order to prove whether the previously established thermal conversion of this cluster into the hydrogenated derivative [Ru3Ir(-H)3(CO)12] also occurs by means of redox or photochemical activation. Two-electron reduction of [Ru3Ir(
3-H)(CO)13] results in the loss of CO and concomitant formation of the dianion [Ru3Ir(
3-H)(CO)12]2–. The latter reduction product is stable in CH2Cl2 at low temperatures but becomes partly protonated above 283K into the anion [Ru3Ir(-H)2(CO)12]– by traces of water. The dianion [Ru3Ir(
3-H)(CO)12]2– is also the product of the electrochemical reduction of [Ru3Ir(-H)3(CO)12] accompanied by the loss of H2. Stepwise deprotonation of [Ru3Ir(-H)3(CO)12] with Et4NOH yields [Ru3Ir(-H)2(CO)12]– and [Ru3Ir(
3-H)(CO)12]2–. Reverse protonation of the anionic clusters can be achieved, e.g., with trifluoromethylsulfonic acid. Thus, the electrochemical conversion of [Ru3Ir(
3-H)(CO)13] into [Ru3Ir(-H)3(CO)12] is feasible, demanding separate two-electron reduction and protonation steps. Irradiation into the visible absorption band of [Ru3Ir(
3-H)(CO)13] in hexane does not induce any significant photochemical conversion. Irradiation of this cluster in the presence of CO with
irr>340nm, however, triggers its efficient photofragmentation into reactive unsaturated ruthenium and iridium carbonyl fragments. These fragments are either stabilised by dissolved CO or undergo reclusterification to give homonuclear clusters. Most importantly, in H2-saturated hexane, [Ru3Ir(
3-H)(CO)13] converts selectively into the [Ru3Ir(-H)3(CO)12] photoproduct. This conversion is particularly efficient at
irr
>340nm. 相似文献
7.
The reactions of LnCl3·6H2O (Ln=Eu or Dy) and Na2[Mo2O3S(HNTA)2]·6H2O afford Na[Mo2O3S(HNTA)2]2·Eu(H2O)9·3H2O (1) (NTA=nitrilotriacetate) and Na{(H2O)6Dy[Mo2O3S(HNTA)2]2}·7.5H2O (2), respectively. The [Mo2O3S(HNTA)2]2− cluster units of 1 are interconnected by Na+ into a 3-D open framework with rutile topology templated by . The coordination of [Mo2O3S(HNTA)2]2− to the slightly smaller Dy3+ ion of greater ionic potential as a consequence of lanthanide contraction has been observed to form the pentanuclear heterometallic {Dy(H2O)6[Mo2O3S(HNTA)2]2}−, which is linked by Na+ and hydrogen bonds between the protonated carboxylate groups into a 3-D supramolecular framework. The weak antiferromagnetic interactions between the Dy3+ ions of 2 have been observed. 相似文献
8.
Bis-paddlewheel heterobimetallic complexes in which palladium(II) is connected to the rare-earth metals(III) [Pd(μ-OOCMe)4Ln(OH2)(μ,η2-OOCMe)]2 × 2HOOCMe (Ln = Nd, Sm, Eu, Yb and Tm) by four acetate bridges were synthesised by the reaction of Pd3(μ-OOCMe)6 with the LnIII acetates. The tetraacetate-bridged complexes were unexpectedly found to be readily transformed by the stoichiometric amount of pivalic acid into the mono-paddlewheel tetrapivalate-bridged analogues in which the paddlewheel structure [Pd(μ-OOCR)4Ln] maintains as established by X-ray crystallography. The role of the intra- and intermolecular H-bonding in these complexes is discussed. 相似文献
9.
A new 3d–4f heterometallic coordination framework, {[Eu(ox)(H2O)4] · [CuBr(2‐pzc)2] · 4H2O} ( 1 ) [ox = oxalate; 2‐pzc = pyrazine‐2‐carboxylate] was synthesized and characterized by elemental analysis, IR spectroscopy and thermal analysis, as well as single‐crystal X‐ray diffraction. Complex 1 represents one 3D supramolecular heterometallic coordination framework that is assembled from rare lanthanide‐ox anionic chains and CuBr(2‐pzc)2 cationic units through hydrogen bonds. 相似文献
10.
Hans J. Breunig Prof. Dr. Enno Lork Ovidiu Moldovan Ciprian I. Raţ 《无机化学与普通化学杂志》2010,636(6):1090-1094
The iron complexes [(Et2Sb)4Fe4(CO)14] ( 1 ), [(nPr2Sb)4Fe3(CO)10] ( 2 ), [{(Me3SiCH2)2Sb}4Fe2(CO)6] ( 3 ), and [2‐(Me2NCH2)C6H4SbFe2(CO)8] ( 4 ) were prepared by reactions of distibanes with Fe2(CO)9. Compounds 1 – 4 were characterized by X‐ray diffraction, 1H NMR and IR spectroscopy as well as mass spectrometry; complex 1 was additionally characterized by density functional calculations. 相似文献