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1.
Abstract

Reactions of Mo(CO)6 with Na2WO4 · 2H2O in refluxing carboxylic anhydride produce the triangular bioxo-capped mixed-metal carboxylate clusters Na[MoW2O2(O2CR)9] (R = Me, 1; Et, 2), the propionate being hydrolyzed in 2M HCl containing ZnCl2 to form [MoW2O2(O2CEt)6(H2O)3]ZnCl4·2H2O (3). Cluster 2 is converted to the incomplete cuboidal tetraanion [MoW2O4(O2CEt)8]4- upon reacting with Cr(CO)6 in propionic anhydride at 120°, the latter species being trapped by Cr and Na± ions in the reaction mixture to afford the octanuclear heterometallic chain-like cluster Na2Cr2 [MoW2O4(O2CEt)8]2 (4). Clusters 1, 3 and 4 have been characterized by X-ray crystallography with the following crystal data, for 1: monoclinic, space group P21/c, a = 16.666(8), b = 11.096(3), c = 16.541(7) Å, β = 94.60(4)°, V = 3048.9 Å3, Z = 4, R, Rw = 0.070, 0.079; for 3, monoclinic, space group Cm, a = 10.259(3), b = 15.756(3), c = 10.870(3) Å, β = 96.18(3)°, V = 1746.8 Å3, Z = 2, R, Rw = 0.028, 0.034; for 4, triclinic, space group P-1, a = 13.013(5), b = 14.005(4), c = 12.357(4) Å, α = 109.71(2), β = 117.77(3), γ = 90.41(3)°, V = 1838.9 Å3, Z = 1, R, Rw = 0.037, 0.042.  相似文献   

2.
3.
The title compound Na5H37P6Mo18O90 1 (Mr=1658) was synthesized under hydrothermal condition and its crystal structure was determined by X-ray diffraction. It crystallized in the monoclinic system, space group P21 with a =14.957(1), b =16.535(1), c = 16.159(1)?,β=108.586(2)°, V=3787.85?3, Dc =3.040g/cm3, Z=2,μ(MoKα)=3.17mm-1, F(000)=3242. The final R and wR are 0.0500 and 0.1535 for 6643 observable reflections with I≥2σ(I), respectively. The result of structure analysis indicates that [Na(HPO4)2(PO4)4-Mo18 O49]5-anions 2 in 1 has the symmetry of C2V, in which each MoVIO6 octahedron is connected to adjacent PO4 tetrahedra through corner-sharing and to adjacent octahedra through edge-sharing or corner-sharing.  相似文献   

4.
采用从头计算MP2和CIS方法分别优化等电子双核d8配合物[Pt2(P2O5H2)4]4-和[Pt2(P2O4CH4)4]4-的基态和激发态结构.结果表明基态Pt-Pt距离分别为0.2905和0.2987nm,与实验的0.2925和0.2980nm符合.NBO计算的Pt-Pt键级以及Pt原子间伸缩振动说明Pt-Pt相互作用具有吸引本质.CIS计算揭示电子激发到Pt-Pt的σ(pz)成键轨道使得相互作用增强.保持激发态几何,含时密度泛函理论(TD-DFT)计算的溶液发射分别为449和475nm,与实验值512和510nm接近.  相似文献   

5.
Three complexes, Na4[DyIII(dtpa)(H2O)]2?·?16H2O, Na[DyIII(edta)(H2O)3]?·?3.25H2O and Na3[DyIII (nta)2(H2O)]?·?5.5H2O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na4[DyIII(dtpa)(H2O)]2?·?16H2O crystallizes in the monoclinic system with P21/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?Å3, Z?=?4, M?=?1517.87?g?mol?1, D c?=?1.879?g?cm?3, μ?=?2.914?mm?1, F(000)?=?3032, and its structure is refined to R 1(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[DyIII(edta)(H2O)3]?·?3.25H2O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?Å3, Z?=?16, M?=?586.31?g?mol?1, D c?=?1.876?g?cm?3, μ?=?3.690?mm?1, F(000)?=?4632, and its structure is refined to R 1(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na3[DyIII(nta)2(H2O)]?·?5.5H2O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?Å3, Z?=?8, M?=?724.81?g?mol?1, D c?=?2.102?g?cm?3, μ?=?3.422?mm?1, F(000)?=?2848, and its structure is refined to R 1(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na4[DyIII(dtpa)(H2O)]2?·?16H2O and Na3[DyIII(nta)2(H2O)]?·?5.5H2O, but monocapped square antiprism for Na[DyIII(edta)(H2O)3]?·?3.25H2O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 1-D zigzag type structure for Na[DyIII(edta)(H2O)3]?·?3.25H2O and a 2-D parallelogram for Na3[DyIII(nta)2(H2O)]?·?5.5H2O. According to thermal analyses, the collapsing temperatures are 356°C for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 371°C for Na[DyIII(edta)(H2O)3]?·?3.25H2O and 387°C for Na3[DyIII(nta)2(H2O)]?·?5.5H2O, which indicates that their crystal structures are very stable.  相似文献   

6.
H8[P4W14O58Na4(H2O)20]·16H2O的合成、晶体结构与性质   总被引:9,自引:2,他引:7  
用水热法合成了H8[P4W14O58Na4(H2O)20]·16H2O,通过X射线单晶衍射、元素分析和IR进行了结构表征,用TG-DTA研究了热稳定性。晶体属三斜晶系,P1空间群,a=1.1379(2)nm,b=1.3632(3)nm,c=1.6271(3)nm;a=78.20(3)°,β=71.20(3)°,γ=71.62(3)°;V=2.2525(8)nm^3,Z=1,Mr=4374.38,D  相似文献   

7.
A new chelate ligand, 5-methyl-1H-pyrazole-3-carboxylic acid (mpca), has been synthesized. This ligand reacts with cupric sulfate to give two supramolecular compounds [Cu(mpca)2(H2O)] · 3H2O (1) and [Cu2(mpca)2(pyr)4] (Pyr = pyridine) (2), which were characterized by elemental analysis and X-ray crystal diffraction. Helical water chain and strong π–π interaction are important for the stability of the 3-D structure of these supramolecules.  相似文献   

8.
Two similar synthetic pathways using the ligand N,N-diisobutylisonicotinamide (L) with anhydrous CoX(2) salts (being X = Cl(-), Br(-)) led to different species: a one-dimensional system, [CoLCl(2)](n), 1, and an ionic product [Co(L)(2)(H(2)O)(4)][CoLBr(3)](2)·2H(2)O, 2, respectively. Compound 1 is a polymer in which ligand L coordinates to tetrahedral Co(II) ions in a bidentate bridging fashion using the pyridine nitrogen and carbonyl oxygen atoms. Compound 2 consists of one octahedral cationic [Co(L)(2)(H(2)O)(4)](2+) entity and two tetrahedral anionic [CoLBr(3)](-) units. In this system, the ligand molecules coordinate only through the pyridine nitrogen atoms. The magnetic properties of 1 and 2 were investigated in the temperature range of 2.0 to 300.0 K and correlations between both (due to the existence of similar features) examined. The study of the magnetic properties of 1 was carried out by considering each Co(II) ion as a perfectly isolated system, hence, J = 0, but taking into account a significant zero-field splitting contribution due to distortions on the tetrahedral environment of the cobalt atoms. The fit of the magnetic susceptibility data together with reduced magnetization vs H/T measurements provided similar parameters (|D| = 10.8 cm(-1), g(⊥) = 1.92, g(‖) = 2.92 for the former and |D| = 11.04 cm(-1)and g = 2.05 for the latter, respectively). On the other hand, the magnetic response of compound 2 has been analyzed using a model which considers the presence of two tetrahedral and one octahedral Co(ii) ions (Co(Td) and Co(Oh)). The study was carried out in two separated blocks, above and below 80 K, where only the most significant effects at each interval of temperature were considered. As a result, the analysis of the magnetic data shows weak antiferromagnetic interactions between the Co(Oh)and the two Co(Td) ions (J = -0.41 cm(-1)) in 2. The best fit parameters were g(Co(Td)) = 2.89, g(Co(Oh)) = 3.50, |D(Co(Td))| = 10.62 cm(-1), |E(Co(Td))| = 2.95 cm(-1), Δ = 240.9 cm(-1) and J(L-S) = -107.1 cm(-1), from where λ was calculated with a final value of -144.8 cm(-1) (J(L-S) = Aκλ). The approximations performed to obtain these values provide reasonable results in agreement with compound 1 and also to other systems in the literature.  相似文献   

9.
Two new decavanadate metal complexes, [Co(H2O)6]2[H2V10O28]·6H2O (1) and (NH4)2[Ca(H2O)7]2[V10O28] (2), have been synthesized under hydrothermal condition by using chlorhydric acid as the initiator at 120 °C. The aqueous NaVO3 solution with an aqueous solution of CoCl2·6H2O were used for generating 1 and aqueous CaCl2·2H2O and NH4VO3 solution were employed for creating 2. Compound 1 consisted of discrete hexa-aqua-cobalt [Co(H2O)6]2+ cations, [H2V10O28]4− anions and non-coordination water molecules. Compound 2 were composed of hepta-aqua-calcium [Ca(H2O)7]2+ cations, ammonium NH4 + and [V10O28]6− anion. For compound 2, the distorted pentagonal bipyramid [Ca(H2O)7]2+ is uncommon. In the crystal lattice, hydrogen bonds played an important role on connecting cations, anions and non-coordinated water molecules to form the three-dimensional network.  相似文献   

10.
Na2[ZnⅡ(ida)2]7H20和Na4[HgⅡ(nta)2]7H20的合成及结构测定   总被引:7,自引:0,他引:7  
金属离子ZnⅠ和HgⅠ分别是生物体必需的微量元素和对人体有害的毒性金属.如何有效地摄取ZnⅠ和排除HgⅠ一直是化学家感兴趣的研究课题.而ZnⅠ和HgⅠ能与各种氨基酸形成配合物,由于它们处于同一族,电子结构都是dl0,故其配位结构只取决于金属离子半径的大小和配体的形状[1~3].  相似文献   

11.
Crystals of bis[(2.2.2-cryptand)sodium] bis[aqua(isothiocyanato)(-isothiocyanato)sodium]: 2[Na(C18H36N2O6)]+ · [Na2(NCS)2(-NCS)2(H2O)2]2– (I) were synthesized and studied by X-ray diffraction analysis. The disordered structure of I (a = 12.715 Å, b = 10.458 Å, c = 21.767 Å, = 102.56°, space group P21/n) was solved by the direct method and refined by the full-matrix least-squares method in anisotropic approximation to R = 0.058 from 3896 independent reflections (CAD4 automated diffractometer, MoK ). The crystal consists of two complex ions [I1]+ and [I2]2– (molar ratio 2 : 1). The Na+ cation of the host–guest cation I1 is coordinated by all eight heteroatoms (6O + 2N) of the cryptand ligand. The coordination polyhedron of this Na+ cation is a distorted cube. The atoms of two groups (CH2–CH2 and CH2–O–CH2–CH2) in the cryptand ligand are disordered over two positions. The independent cation Na+ of the centrosymmetric binuclear complex anion I2 is coordinated by one bifurcated O atom of the disordered water molecule and by three N atoms of the SCN ligands (including two bridging ligands). The coordination polyhedron of this Na+ caiotn is a distorted tetrahedron. The complex ions in the crystal structure of I are united by hydrogen bonds.  相似文献   

12.
The title compounds crystallize such that bilayers of calixarenes are separated by hydrophilic layers. In each case the transition metal has, in addition to a primary sphere of ligands, a second-sphere coordination by a calixarene. [(H2O)5Ni(NC5H5)]2(Na)[calix[4]arene sulfonate]·3.5 H2O,1, crystallizes in the triclinic space groupP \(\bar 1\) witha = 12.487(4),b = 14.281(2),c = 15.055(5) Å, α = 85.66(2), β = 80.07(2), γ = 80.48(2)°, andD c = 1.64 g cm?3 forZ = 2. Refinement based on 2441 observed reflections led to a finalR value of 0.066. There are two different environments for the nickel-containing cations: one is positioned within the hydrophilic layer with the pyridine ligand intercalated into the hydrophobic calixarene bilayer and the other is also positioned within the hydrophilic layer, but the pyridine ligand is inserted into the hydrophobic cavity of the calix[4]arene. [(H2O)4Cu(NC5HS)2](H3O)3[calix[4]arene sulfonate]·10 H2O,2, crystallizes in the triclinic space groupP \(\bar 1\) witha = 15.438(4),b = 15.727(6),c = 12.121(9) Å, α = 112.74(4), β = 102.02(4), γ = 85.34(4)°, andD c = 1.57 g cm?3 forZ = 2. Refinement based on 3925 observed reflections led to a finalR value of 0.107. The structure is similar to that of 1 except that the one copper-containing cation spans the hydrophilic layer and is intercalated into the bilayer of calixarenes on one side and positioned into the calixarene cavity on the other.  相似文献   

13.
标题晶体属斜方晶系,空间群Pbn2_1,a=9.086(2),b=13.439(3),c=22.858(11),V=2791,Z=4,Dc=1.927g/cm~3。在CAD—4衍射仪上收集强度数据,采用直接法和Fourier技术解出结构,并用全矩降最小二乘法修正。对于1180个独立衍射最终偏离因子0.067。结构中的阴离子与其同系物[(CH_3)_4-N]_2K(Mo_2O(S_2)_3(NO)_2]·H_2O中的阴离子配位情况相似。只是结构中的Mo—S与Mo—O键长有差异。这种差异在两者的红外光谱上有着相应的表现。  相似文献   

14.
Binary complex salts, [Co(En)3][Fe(CN)6] · 2H2O and [Co(En)3]4[Fe(CN)6]3 · 15H2O, are synthesized. The properties of the salts and their thermolysis in air, dihydrogen, and argon are studied. Oxides of the central ions of the binary complex salts are found to be the thermolysis products in an oxidative atmosphere. Solid solutions (intermetallic compounds) CoFe are the thermolysis products in the reductive atmosphere, whereas intermetallides containing considerable amounts of C and N and an impurity of Co and Fe oxides are the thermolysis products in an inert atmosphere. Gaseous thermolysis products in dihydrogen and argon are NH3, hydrocarbons, and ethylenediamine.  相似文献   

15.
2-硝基-4-羧基-苯氧乙酸(ncpo)与两种金属离子Na(Ⅰ)和Co(Ⅱ)进行配位桥连得到配位聚合物[Na2Co(ncpo)2·4H2O].,采用元素分析和红外光谱对得到的配合物进行了表征.X单晶衍射仪测定晶体结构表明:[ Na2Co(ncpo)2·4H2O]n属于三斜晶系Pi空间群,晶胞参数:a=6.9212(2)...  相似文献   

16.
The oxalato-titanium(IV)-containing, dimeric 18-tungsto-2-phosphate [Ti8(C2O4)8P2W18O76(H2O)4]18? (1) and the 32-tungsto-4-phosphate [Ti6(C2O4)4P4W32O124]20? (2) are formed upon reaction of the oxalato-titanium complex [TiO(C2O4)2]2? with the trilacunary Keggin precursor [A-α-PW9O34]9? and the hexalacunary Wells–Dawson precursor [H2P2W12O48]12?, respectively. Polyanion 1 consists of two {PW9} units encapsulating eight titanium centers and connected to each other via two Ti–O–Ti bridges, and crystallizes as a mixed potassium-sodium-lithium salt in the triclinic space group $P{\bar{1}}$ . Polyanion 2 comprises two {P2W16} units containing each two titanium atoms, and the two half-units are connected via two titanium atoms decorated by two oxalate groups each, and crystallizes as a mixed potassium-lithium salt in the rhombohedral space group $R{\bar{3}}c$ . Polyanions 1 and 2 were characterized in the solid state by single-crystal XRD, FT-IR, and TGA, whereas polyanion 2 was also investigated by 31P and 183W NMR.  相似文献   

17.
Abstract  The compound [NH4][(CH3)2NH2]2[Ta(C2O4)4]·2H2O has been synthesized and characterized by elemental and TG/DTA analyses, IR spectroscopy and by the single-crystal X-ray diffraction study. The structure comprises the [Ta(C2O4)4]3− anion, NH4 + and [(CH3)2NH2]+ cations and crystallization water molecules. The Ta atom is octacoordinated by oxygen atoms from four bidentate oxalate groups forming a coordination polyhedron close to the triangular dodecahedron. The charge-assisted hydrogen bonds from both cations connect the [Ta(C2O4)4]3− anions into a three-dimensional framework. Graphical Abstract  The synthesis and properties of [NH4][(CH3)2NH2]2[Ta(C2O4)4]·2H2O, the first structurally characterized compound with the tetra(oxalato)tantalate(V) anion, is reported.   相似文献   

18.
《Polyhedron》1999,18(21):2781-2785
The compounds (NH4)6[Mo6V2O24(C2O4)2]·6H2O (I) and (NH4)4[H2Mo2V2O12(C2O4)2]·2H2O (II) have been prepared from molybdenum(VI) oxide and ammonium vanadate in aqueous solution through the addition of ammonium oxalate, and their structures determined by X-ray structure analysis. Whereas the molybdovanadate anion [Mo6V2O24(C2O4)2]6− found in (I) consists of six MoO6 and two VO6 edge-sharing octahedra of the γ-[Mo8O26]4− type structure, the tetranuclear anion [H2Mo2V2O12(C2O4)2]4− of (II) adopts the structure with a M4O16 core. Both complexes contain bidentate oxalato ligands bonded to the vanadium ions. In both crystal structures the molybdovanadate anions are mutually hydrogen bonded by ammonium ions and water molecules.  相似文献   

19.
过氧多酸盐[NBu4]3[M(O2)W5O18]的合成及表征   总被引:1,自引:0,他引:1  
过渡金属过氧化合物是一类性能良好的催化剂,在有机合成中得到广泛的应用[1,2].过氧多酸催化过氧化氢氧化有机物的反应,近年来倍受重视[3~5].  相似文献   

20.
After a short survey of what is the present state of the cyclophosphates associated with the organic molecule NH2(CH2)4NH2, we report chemical preparation and crystal structure for a new example of such compounds. [NH3(CH2)4NH3]2P4O12.2H2O is monoclinic (S.G. : P21/n), with Z = 2 and the following unit-cell parameters : a = 7.6728(8) Å, b = 18.962(3) Å, c = 7.9789(9) Å β = 111.751(9)°. Bidimensional layer arrangement of P4O12 rings connected to the water molecules thanks to weak H-bonds run parallel to the ab plane. The organic groupements located between these inorganic planes perform the three-dimensional cohesion by NH····O hydrogen bonds.  相似文献   

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