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1.
1 INTRODUCTION In the last decade, cyano-bridged Prussian Blueanalogues[1] have been intensively studied from theviewpoint of application as functionalized molecule-based magnets[2], chemical sensor materials[3], fluo-rescent materials[4] and zeolitic-type materials[5, , 6]etc. In 1976, a series of cyano-bridged three-dimen-sional rare earth hexacyanometalates(IIILnM(CN)6?nH2O (M = Fe or Cr, n = 4 or 5) were crystallized andsubjected to single-crystal X-ray analysis[7]. …  相似文献   

2.
1 INTRODUCTION In the past few years, more extensive attention had been paid to the research on the chemistry of the heterometallic complexes containing simultaneously lanthanide (Ln) and transition metal ions[1~9]. Interest has been largely focused on the magnetic properties resulting from the Gd(III)-Cu(II) couple, which has been found to be directly ferromagnetic irrespective of the structural details[1~5]. Recent studies have further revealed that the magnitude of the ferromagnet…  相似文献   

3.
Li F  Sevov SC 《Inorganic chemistry》2012,51(4):2706-2708
Reported is the first rational synthesis of a trisubstituted deltahedral Zintl ion, [Ge(9){Si(SiMe(3))(3)}(3)](-) in this case, by the addition of the three substituents in a reaction of the parent naked deltahedral Zintl ion Ge(9)(4-) with {(Me(3)Si)(3)Si}Cl. The new species were crystallized and structurally characterized in [K(2,2,2-crypt)](2)[Ge(9){Si(SiMe(3))(3)}(3)] (monoclinic, P2(1)/c, a = 26.497(3) ?, b = 24.090(2) ?, c = 29.268(3) ?, β = 113.888(2)°, V = 17082(3) ?(3), Z = 8, R1/wR2 = 0.0436/0.0812 for the observed data and 0.1023/0.1010 for all data).  相似文献   

4.
1 INTRODUCTION Over the last decade, there has been continuous interest in cyanide-bridged lanthanide-transition me- tal complexes due to their extensive applications in preparing rare earth orthoferrites[1], chemical sensor materials[2], fluorescent ma…  相似文献   

5.
A novel electron-poor Eu(6.5)Gd(0.5)Ge? compound adopts the Ca?Sn?-type structure (space group Pnma, Z = 4, a = 7.5943(5) ?, b = 22.905(1) ?, c = 8.3610(4) ?, and V = 1454.4(1) ?3). The compound can be seen as an intergrowth of the Gd?Si?-type (Pnma) R?Ge? (R = rare earth) and FeB-type (Pnma) RGe compounds. The phase analysis suggests that the Eu(7-x)Gd(x)Ge? series displays a narrow homogneity range of stabilizing the Ca?Sn? structure at x ≈ 0.5. The structural results illustrate the structural rigidity of the 2(∝)[R?X?] slabs (X = p-element) and a possibility for discovering new intermetallics by combining the 2(∝)[R?X?] slabs with other symmetry-approximate building blocks. Electronic structure analysis suggests that the stability and composition of Eu(6.5)Gd(0.5)Ge? represents a compromise between the valence electron concentration, bonding, and existence of the neighboring EuGe and (Eu,Gd)?Ge? phases.  相似文献   

6.
Two new intermetallic compounds, Yb(2)Ga(4)Ge(6) and Yb(3)Ga(4)Ge(6), were obtained from reactions in molten Ga. A third compound, Eu(3)Ga(4)Ge(6), was produced by direct combination of the elements. The crystal structures of these compounds were studied by single-crystal X-ray diffraction. Yb(2)Ga(4)Ge(6) crystallizes in an orthorhombic cell with a=4.1698(7), b=23.254(4), c=10.7299(18) A in the polar space group Cmc2(1). The structure of RE(3)Ga(4)Ge(6) is monoclinic, space group C2/m, with cell parameters a=23.941(6), b=4.1928(11), c=10.918(3) A, beta=91.426(4) degrees for RE=Yb, and a=24.136(2), b=4.3118(4), c=11.017(1) A, beta=91.683(2) degrees for RE=Eu. The refinement [I>2 sigma(I)] converged to the final residuals R(1)/wR(2)=0.0229/0.0589, 0.0411/0.1114, and 0.0342/0.0786 for Yb(2)Ga(4)Ge(6), Yb(3)Ga(4)Ge(6), and Eu(3)Ga(4)Ge(6), respectively. The structures of these two families of compounds can be described by a Zintl concept of bonding, in which the three-dimensional [Ga(4)Ge(6)](n-) framework serves as a host and electron sink for the electropositive RE atoms. The structural relation of RE(3)Ga(4)Ge(6) to of Yb(2)Ga(4)Ge(6) lies in a monoclinic distortion of the orthorhombic cell of Yb(2)Ga(4)Ge(6) and reduction of the [Ga(4)Ge(6)] network by two electrons per formula unit. The results of theoretical calculations of the electronic structure, electrical transport data, and thermochemical and magnetic measurements are also reported.  相似文献   

7.
NaAuGe, a Further Ternary Auride with Ethane Analogous Ge2Au6 Building Units Black, brittle single crystals of NaAuGe were obtained by the reaction of NaN3, gold sponge and germanium at 800°C. The structure was determined from X-ray single-crystal diffractometry data: space group Imm2, Z = 4, a = 4.422(1) Å, b = 7.238(2) Å, c = 7.531(2) Å, R1/wR2 = 0.0195/0.0482, N(F) ≥ 2σ(F) = 811 and N(var.) = 21. NaAuGe crystallizes in a new ternary variant of the KHg2 (CeCu2)structure type. Gold and germanium form puckered [AuGe3/3] layers with trigonal planar coordinated gold. The [AuGe3/3] nets are connected to a framework structure via Ge—Ge contacts along [010] which consist of ethane analogous Ge2Au6 building units. The sodium atoms are placed in channels of the Au—Ge framework structure which run along [100] and [010].  相似文献   

8.
Zhang CY  Zhou LJ  Chen L 《Inorganic chemistry》2012,51(13):7007-7009
New quaternary tellurides, Cs(2)Ge(3)M(6)Te(14) (M = Ga, In), were discovered by solid-state reactions. These compounds crystallize in space group P3ml (No. 164), with a = b = 8.2475(2) ?, c = 14.2734(8) ?, and V = 840.82(6) ?(3) (Z = 1) for Cs(2)Ge(3)Ga(6)Te(14) (1) and a = b = 8.5404(2) ?, c = 14.6766(8) ?, and V = 927.07(6) ?(3) (Z = 1) for Cs(2)Ge(3)In(6)Te(14) (2). The remarkable structural feature is the novel three-dimensional [Ge(3)M(6)Te(14)](2-) anionic framework made by condensed In(6)Te(14) (or Ga(6)Te(14)) layers that are connected alternately by dimeric Ge(3+)(2)Te(6) units and Ge(2+)Te(6) octahedra along the c direction. The presence of Ge centers with different oxidation states is also supported by the results of the electron localization function calculation and X-ray photoelectron spectroscopy measurement.  相似文献   

9.
1 INTRODUCTION Polyoxometalates, a rich and remarkable classof inorganic cluster system[1], exhibit diverse appli-cation possibilities due to their topological and elec-tronic properties, ranging from their well-known roleas reagents in analytical, b…  相似文献   

10.
Two new iron-sulfur carbonyl complexes, [Fe2(SC6H4Cl)2(CO)6]?0.5(Et2O) 1 and [Fe3(SC6H4NH2)6(CO)6]?2(MeOH) 2, have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. Crystal data for 1: monoclinic, C2/c, a = 18.4439(8), b = 11.0999(5), c = 25.1830(10) ?, β = 97.0370(10)o, V = 5116.8(4) ?3, Z = 8, C20H13Cl2Fe2O6.50S2, Mr = 604.02, Dc = 1.568 g/cm3, μ = 1.540 mm–1, F(000) = 2424, the final R = 0.0545 and wR = 0.1454 for 3443 observed reflections with I > 2σ(I); 2: monoclinic, P21/n, a = 12.350, b = 26.3050(11), c = 16.057 ?, β = 97.891(3)°, V = 5166.9(2) ?3, Z = 4, C44H44Fe3N6O8S6, Mr = 1144.76, Dc = 1.472 g/cm3, μ = 1.128 mm–1, F(000) = 2352, the final R = 0.0442 and wR = 0.1197 for 7978 observed reflections with I > 2σ(I). Complex 1 contains one iron dimer, in which two tricarbonyliron(I) fragments are bridged together by two 4-chlorophenylthiolate ligands, whereas complex 2 contains a linear tri-iron cluster, in which two terminal tricarbonyliron(II) fragments and the central Fe(II) atom are linked together by six 4-aminophenylthiolate bridging ligands.  相似文献   

11.
A novel compound of chiral spiro{1-bromo-4-hydroxy-5-N-cyclohexyl-butyro- lactam-6-oxo-dirings[3.1.0]hexane-2,3?-(4?-diphenylcarbinol-5?-menthyloxy-butyrolatone)} was synthesized via tandem nucleophilic substitution reaction under mild conditions, and its structure was determined by IR , 1H NMR, elemental analysis and X-ray diffraction. The crystal structure of this compound is of monoclinic system, space group P21 with a = 9.7356(9), b = 12.2760(12), c = 14.9577(14) ?, β = 101.0300(10)°, Mr = 680.66, Z = 2, V = 1754.6(3) ?3, Dc = 1.288 g/cm3, μ(MoKα) = 1.216 mm-1, F(000) = 716, the final R = 0.0434 and wR = 0.0996.  相似文献   

12.
A new two-dimensional framework germanate, Ge3O5(OH)4[C2N2H10] (denoted ICMM-8), with a 3:9 Ge:O ratio has been synthesized, using a mixture of pyridine, water, and ethanol as the solvent and 1,4-diazabicyclo[2.2.2]octane and ethylenediamine as the structure-directing agents, under solvothermal conditions. The structure was determined by single-crystal X-ray diffraction. In this new compound, the GeO2 natrolite-type infinite four and eight R-containing layers appears for the first time in a pure GeO2 framework. The total 2D structure is built up from SBU-6, four tetrahedra, and two octahedra. The hydroxyl groups occupy four positions of each octahedral germanium atom. The compound is characterized by IR spectra and TGA-DTA. Crystal data: Ge3O5(OH)4[C2N2H10], monoclinic space group P2(1)/c; a = 11.3570(9) Angstroms, b = 8.8819(7) Angstroms, c = 9.9200(8) Angstroms, beta = 90.710(1), V = 1000.6(1) Angstroms(3), Z = 4, R(1) = 0.044 (I > 2(I)), and wR(2) = 0.1051 (all data).  相似文献   

13.
合成了新型邻菲咯啉镁(II)配合物 [Mg(H2O)4(phen)](phen)[C6H4(COO)2]?H2O, 并对其进行了元素分析、IR、TG、X-射线衍射等表征。单晶衍射结果表明, 该配合物晶体属单斜晶系, 空间群为 P21/c, 晶胞参数:a = 11.873(2), b = 31.992(6), c = 8.144(2) ?, β = 93.98(3), V = 3085.9(11)?3, Z = 4, F(000) = 1336, Dc = 1.375 g/cm3, μ(MoKα) = 0.120 mm?1。对于 6889[ Rint = 0.0264]个独立衍射点, 有 3939 个可观测点满足(I≥2σ (I)), 最终的偏离因子 R = 0.0430, wR = 0.1294。标题配合物由 1 个邻菲咯啉合镁阳离子[Mg(H2O)4(phen)]2+、1 个邻苯二甲酸根阴离子C6H4(COO)2)2–、1 个溶剂邻菲咯啉分子和 1 个结晶水分子组成。中心 Mg(II)离子为六配位, 六个配位原子形成畸变的 MgN2O4八面体构型。  相似文献   

14.
EuMg6Sn3.67 has been synthesized by reacting the mixture of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction study. EuMg6Sn3.67 crystallizes in hexagonal space group P63/m (No. 176) with a = 11.7259(4), c = 4.5507(2), V = 541.88(4)3 , Z = 2, Mr = 734.60, Dc = 4.502 g/cm3 , μ = 14.348 mm-1 , F(000) = 638, the final R = 0.0128 and wR = 0.0378 for 464 observed reflections with Ⅰ > 2σ(Ⅰ). EuMg6Sn3.67 is closely related to the Ba2Mg12Ge7.33 structure type and features a three-dimensional Mg6Sn3.67 framework with one-dimensional hexagonal tunnels along the c-axis occupied by the Eu atoms. Electronic structure calculation indicates that the title compound is metallic.  相似文献   

15.
Synthesis and Crystal Structure of [La(BTC)(H2O)6]n   总被引:1,自引:0,他引:1  
1 INTRODUCTION desired topologies owing to their rich coordination modes[8~12] and we have been exploring the chemi- The assembly of metal-organic infinite frame- stry of coordination polymers constructed by tran- works via coordination of metal ions with multifunc- sition metals and benzoic multicarboxylic acids[13~16]. tional organic ligands is a field of increasing inte- In addition, lanthanide ions have high affinity for rest[1~4]. A rational designed and predictable coor- hard donor a…  相似文献   

16.
1 INTRODUCTION The chemistry of polyoxometalates has been at- tracting much attention due to the richness in their structures, electron and proton storage abilities, ther- mal stability and applications in catalysis, medicine and surface sciences[1~3]. In recent years, the mixed- valence as well as full oxidized vanadium polyoxo- anions have been crystallized with a variety of orga- nic molecules as counteranions[4~8]. However, the guiding principles of the crystal structures of poly- o…  相似文献   

17.
1INTRODUCTIONRecentlythedesignandsynthesisoftinsulfide-basedsolidstatematerialshasreceivedmuchattentionowningtotheirinterestingoptical,catalyticandelectricalpropertiesfordeviceappli-cations[1].Becauseoftheversatilecoordinationcharacteristicsoftinandsulfur…  相似文献   

18.
The ternary germanide Tb4FeGe8 was obtained from Ga flux reactions. The crystal structure studied with single-crystal X-ray diffraction revealed the existence of an orthorhombic average substructure (Cmcm, Z=1) with cell parameters a = 4.1118(14) A, b=15.844(5) A, and c=3.9885(15) A. The refinement [I > 2sigma(I)] converged to final residuals R1/wR2 = 0.0363/0.0893. The average structure (CeNiSi2-type) consists of a 3D [Fe1/4Ge2] framework where Ge atoms form a square net and Fe atoms reside alternatively above and below it with only 1/4 occupation probability. X-ray and electron diffraction studies showed a modulation in the Ge net. The modulated structure was refined based on a 4-fold monoclinic supercell (P2(1)/n) with parameters a = 5.7315(11) A, b = 15.842(3) A, c = 11.438(2) A, and beta = 91.724(4) degrees with R1/wR2 = 0.0643/0.1735 and uncovered a severe distortion of the Ge square net. The Ge atoms are displaced to form an array of cis-trans chains. The Ge-Ge distances within these chains are distinctively bonding, whereas those between the chains are nonbonding. Results of the electronic structure calculations and magnetic measurements are also reported. The structural distortions found in Tb4FeGe8 cast a doubt onto the correctness of many of the reported REM1-xGe2 disordered compounds and call for reinvestigation.  相似文献   

19.
By reaction of [NBu(4)](2)[Pt(2)(&mgr;-C(6)F(5))(2)(C(6)F(5))(4)] with 1,8-naphthyridine (napy), [NBu(4)][Pt(C(6)F(5))(3)(napy)] (1) is obtained. This compound reacts with cis-[Pt(C(6)F(5))(2)(THF)(2)] to give the dinuclear derivative [NBu(4)][Pt(2)(&mgr;-napy)(&mgr;-C(6)F(5))(C(6)F(5))(4)] (2). The reaction of several HX species with 2 results in the substitution of the bridging C(6)F(5) by other ligands (X) such as OH (3), Cl (4), Br (5), I (6), and SPh (7), maintaining in all cases the naphthyridine bridging ligand. The structure of 3 was determined by single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P2(1)/n, with a = 12.022(2) ?, b = 16.677(3) ?, c = 27.154(5) ?, beta = 98.58(3) degrees, V = 5383.2(16) ?(3), and Z = 4. The structure was refined to residuals of R = 0.0488 and R(w) = 0.0547. The complex consists of two square-planar platinum(II) fragments sharing a naphthyridine and OH bridging ligands, which are in cis positions. The short Pt-Pt distance [3.008(1) ?] seems to be a consequence of the bridging ligands.  相似文献   

20.
Single crystal and bulk powder samples of the quaternary lanthanum copper oxysulfides La5Cu6.33O4S7 and La5Cu6O4S7 have been prepared by means of high-temperature sealed-tube reactions and spark plasma sintering, respectively. In the structure of La 5Cu6.33O4S7, Cu atoms tie together the fluorite-like (2)infinity[La5O4S(5+)] and antifluorite-like (2) infinity[Cu6S6(5-)] layers of La5Cu6O4S7. The optical band gap, E g, of 2.0 eV was deduced from both diffuse reflectance spectra on a bulk sample of La5Cu6O4S7 and for the (010) crystal face of a La 5Cu6.33O4S7 single crystal. Transport measurements at 298 K on a bulk sample of La 5Cu 6O 4S 7 indicated p-type metallic electrical conduction with sigma electrical =2.18 S cm(-1), whereas measurements on a La 5Cu6.33O4S7 single crystal led to sigma electrical =4.5 10(-3) S cm(-1) along [100] and to semiconducting behavior. In going from La 5Cu6O4S7 to La5Cu6.33O4S7, the disruption of the (2)infinity[Cu6S6(5-)] layer and the decrease in the overall Cu(2+)(3d(9)) concentration lead to a significant decrease in the electrical conductivity.  相似文献   

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