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1.
Polarized absorption spectra of Ba(MnO4)2·3H2O/Ba(ClO4)2·3H2O mixed single crystals are reported at 4.2°K. Previous 1T21A1 assignments for the 5200 Å and 3000 Å absorption bands of MnO4 are substantiated; further support is provided for the 1T11A1 assignment of the 3600 Å absorption band of MnO4. The site-splitting of the 5200 Å 1T2 state is E(1E)−E(1A) ≈ −150 cm−1; that of the 3000 Å 1T2 state is E(1E)−E(1A) ≈ 300 cm−1. A significant e vibronic intensity component is observed in the 5200 Å 1T2 state.  相似文献   

2.
A new synthesis of trisfluoroacetylactone (TFA) and hexafluoroacetylactone (HFA) Nd complexes: Nd(TFA)3 · 2H2O and Hd(HFA)3 · 2H2O is reported. The photoacoustic (PA) spectra in the 300–800 nm region of the compounds NdCl3 · 6H2O, Nd(TFA)3 · 2H2O and Nd(HFA)3 · 2H2O are reported. The PA absorption bands are assigned and their relative intensities represented by intensity branching vectors are calculated. The perturbation of the ligand on the energy levels of Nd3+ ion is discussed and a model of the relaxation process of Nd(HFA)3 · 2H2O is proposed based on its PA and absorption spectra.  相似文献   

3.
The complex [Re2(HPO4)2(H2PO4)2(H2O)2] · 4H2O (I) was synthesized and investigated by conductometric, potentiometric, electronic and vibration spectroscopic methods. Thermal behavior of the title compound was studied and its molecular structure was determined from X-ray diffraction data. In the dimeric neutral complex, the bridging pairs of the hydrophosphate and dihydrophosphate groups close four five-membered Re-O-P-O-Re chelate rings. The O atom of water molecule occupies the axial position in the metal coordination polyhedron. The Re-Re distance 2.2168(8) ? corresponds to quadruple bond. Original Russian Text ? A.V. Shtemenko, V.G. Stolyarenko, K.V. Domasevich, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 2, pp. 83–88.  相似文献   

4.
A cobalt phosphonate (H3O)6·[Co4(H2O)4(HPMIDA)2(PMIDA)2)]·2H2O, 1, has been synthesized from a mild solvothermal reaction of Co(II) ion with N-(phosphonomethyl)iminodiacetic acid (H4PMIDA). Compound 1 crystallizes in the triclinic space group with cell parameters of , , , α=93.06(3)°, β=99.66(3)°, γ=90.34(3)° and Z=1. Compound 1 shows a novel tetra-nuclear molecular structure. In the crystal lattice, molecules of 1 hydrogen bond to each other to form two-dimensional (2D) layers, which are further linked together by the co-crystallized H2O molecules and H3O+ counter ions through hydrogen bonding to form the 3D supramolecular network. Thermogravimetric analysis, IR spectrum, magnetic susceptibility and luminescent spectra are given.  相似文献   

5.
The syntheses and structural determination of NdIII and ErIII complexes with nitrilotriacetic acid (nta) were reported in this paper. Their crystal and molecular structures and compositions were determined by single-crystal X-ray structure analyses and elemental analyses, respectively. The crystal of K3[NdIII(nta)2(H2O)]·6H2O complex belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5490(11) nm, b=1.3028(9) nm, c=2.6237(18) nm, β=96.803(10)°, V=5.257(6) nm3, Z=8, M=763.89, Dc=1.930 g cm−3, μ=2.535 mm−1 and F(000)=3048. The final R1 and wR1 are 0.0390 and 0.0703 for 4501 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0758 and 0.0783 for all 10474 reflections, respectively. The NdIIIN2O7 part in the [NdIII(nta)2(H2O)]3− complex anion has a pseudo-monocapped square antiprismatic nine-coordinate structure in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly. The crystal of the K3[ErIII(nta)2(H2O)]·5H2O complex also belongs to monoclinic crystal system and C2/c space group. The crystal data are as follows: a=1.5343(5) nm, b=1.2880(4) nm, c=2.6154(8) nm, b=96.033(5)°, V=5.140(3) nm3, Z=8, M=768.89, Dc=1.987 g cm−3, μ=3.833 mm−1 and F(000)=3032. The final R1 and wR1 are 0.0321 and 0.0671 for 4445 (I>2σ(I)) unique reflections, R2 and wR2 are 0.0432 and 0.0699 for all 10207 reflections, respectively. The ErIIIN2O7 part in the [ErIII(nta)2(H2O)]3− complex anion has the same structure as NdIIIN2O7 part in which the eight coordinate atoms (two N and six O) are from the two nta ligands and a water molecule coordinate to the central NdIII ion directly.  相似文献   

6.
A novel polyoxometalate {[Ni(enMe)2]2[Ni(enMe)2(H2O)]2[As2W18Ni4(enMe)2O68]}·2H3O·2H2O (1) (enMe = 1,2-propylenediamine) has been synthesized and characterized, which is the first high-dimensional structure constructed from sandwich-type transition metal substituted tungstates and transition metal coordination groups.  相似文献   

7.
A new form of cobalt succinate has been discovered using high-throughput methods and its structure was solved by single crystal X-ray diffraction. Co7(C4H4O4)4(OH)6(H2O)37H2O crystallizes in the monoclinic space group P21/c with cell parameters: a=7.888(2) Å, b=19.082(6) Å, c=23.630(7) Å, β=91.700(5)°, V=3555(2) Å3, R1=0.0469. This complex structure, containing 55 crystallographically distinct non-hydrogen atoms, is compared to the previously reported nickel phase, characterized using ab initio structure solution from synchrotron powder diffraction data.  相似文献   

8.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS)2(hmt)2(H2O)2][Co(NCS)2(H2O)4] (H2O) (I), assembled by hexamethylenetetramine and octahedral Co(II) metal ions, are reported. Crystal data for I: Fw 387.34, a=9.020(8), b=12.887(9), c=7.95(1) Å, =96.73(4), β=115.36(5), γ=94.16(4)°, V=820(1) Å3, Z=2, space group=P−1, T=173 K, λ(Mo-K)=0.71070 Å, ρcalc=1.718567 g cm−3, μ=17.44 cm−1, R=0.088, Rw=0.148. An interesting two-dimensional network is assembled via hydrogen bonds through coordinated and free water molecules. The d–d transition energy levels of Co(II) ion are determined by UV–vis spectroscopy and calculated by ligand field theory. The calculated results agree well with experiment ones.  相似文献   

9.
Three new hydrated scandium selenites have been hydrothermally synthesized as single crystals and structurally and physically characterized. Sc2(SeO3)3·H2O crystallizes as a new structure type containing novel ScO7 pentagonal bipyramidal and ScO6+1 capped octahedral coordination polyhedra. Sc2(SeO3)3·3H2O contains typical ScO6 octahedra and is isostructural with its M2(SeO3)3·3H2O (M=Al, Cr, Fe, Ga) congeners. CsSc3(SeO3)4(HSeO3)2·2H2O contains near-regular ScO6 octahedra and has essentially the same structure as its indium-containing analogue. All three phases contain the expected pyramidal [SeO3]2- selenite groups. Crystal data: Sc2(SeO3)3·3H2O, Mr=524.85, trigonal, R3c (No. 161), , , , Z=6, R(F)=0.018, wR(F2)=0.036; Sc2(SeO3)3·H2O, Mr=488.82, orthorhombic, P212121 (No. 19), , , , , Z=4, R(F)=0.051, wR(F2)=0.086; CsSc3(SeO3)4(HSeO3)2·2H2O, Mr=1067.60, orthorhombic, Pnma (No. 62), , , , , Z=4, R(F)=0.035, wR(F2)=0.070.  相似文献   

10.
The reaction between metallic barium and fluoroisopropanol or alcoholysis of [Ba(OPri)2] produces a pentanuclear fluoroalkoxide. Its X-ray structure determination showed its formulation to correspond to Ba55-OH)[μ3-OCH(CF3)2]42-OCH(CF3)2]4 [OCH(CF3)2](THF)4(H2O)·THF. The metallic core is based on a square pyramid encapsulating an hydroxo ligand. In addition to the barium---alkoxide bonds [2.53(3)–2.86(3) Å] neutral O-donors, four THF [2.82(2)–2.86(3) Å] and one H2O [2.79(3) Å] and secondary barium---fluorine interactions [2.99(2)–3.31(2) Å] ensure high coordination numbers, from 9 to 11 for the metal centers. Hydrogen bonding between the apical fluoroisopropoxide, the water molecule and one THF molecule, non-bonded to a metal center, accounts for the stability of the hydrate and illustrates the Lewis acidity of fluoroalkoxides. Thermal decomposition leads to BaF2.  相似文献   

11.
A new layered indium phosphate [Co(en)3][In3(H2PO4)6(HPO4)3]·H2O (1) has been synthesized solvothermally by using a racemic mix of chiral metal complex Co(en)3Cl3 as a template. Its structure is determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, ICP, NMR and TG analyses. The inorganic layer is built up by alternation of In-centred octahedra (InO6) and P-centered tetrahedra (PO3(OH), PO2(OH)2, PO2(=O)(OH) and PO(=O)(OH)2) forming a 4.12-net. The metal complex cations locate in the interlayer region and interact with the host network through H-bonds. It is the first indium phosphate compound templated by a transition-metal complex and is isostructural with GaPO-CJ14. Crystal data: 1, monoclinic, space group P21/m (No. 11), a=9.1700(18) Å, b=22.6923(5) Å, c=9.9116(2) Å, β=107.87(3)°, Z=4, R1[I>2σ(I)]=0.0287 and wR2(all data)=0.0939.  相似文献   

12.
Two solid-state coordination compounds of rare earth metals with glycin, [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O and [ErY(Gly)6(H2O)4](ClO4)6·5H2O were synthesized. The low-temperature heat capacities of the two coordination compounds were measured with an adiabatic calorimeter over the temperature range from 78 to 376 K. [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O melted at 342.90 K, while [ErY(Gly)6(H2O)4](ClO4)6·5H2O melted at 328.79 K. The molar enthalpy and entropy of fusion for the two coordination compounds were determined to be 18.48 kJ mol−1 and 53.9 J K−1 mol−1 for [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O, 1.82 kJ mol−1 and 5.5 J K−1 mol−1 for [ErY(Gly)6(H2O)4](ClO4)6·5H2O, respectively. Thermal decompositions of the two coordination compounds were studied through the thermogravimetry (TG). Possible mechanisms of the decompositions are discussed.  相似文献   

13.
葛红光   范广  陈三平  高胜利 《化学学报》2006,64(24):2501-2504
在水溶液中合成了离子型配合物[Ni(phen)2(H2O)2][Ni(PDC)2]•7H2O (H2PDC=吡啶-2,6-二甲酸, phen=1,10-菲啰啉). 通过元素分析、红外光谱、单晶X射线衍射以及热重分析对配合物进行了表征. 晶体数据解析表明, 化合物属于三斜晶系, 空间群为P1, a=1.0092(4) nm, b=1.4599(6) nm, c=1.4933(5) nm, α=73.982(2)°, β=78.652(2)°, γ=75.184(3)°, V=2.0256(13) nm3, Z=2, F(000)=1004, μ=1.014 mm-1, R1=0.0538, wR2=0.1493. 配合物中的结晶水分子形成一个(H2O)12水簇, (H2O)12水簇通过氢键连接为二维水网, 最终构成三维超分子网络.  相似文献   

14.
Two fluoride sulfates,K2Mn3(SO4)3F2·4H2O(Ⅰ) and Rb2Mn3(SO4)3F2·2H2O (Ⅱ) are obtained by water solution method.Single-crystal X-ray diffraction analysis indicated that they crystallize in space groups of Cmc21.Their structures feature a pseudo-KTP structure consisting of interconnecting[Mn3(SO4)3F2(H2O)2] layers,which are further packing along the a axis with alkali metal cations balancing the charges.The structure relationships between the two compounds are discussed.Secondharmonic generation measurements manifest that Ⅰ and Ⅱ have similar second-harmonic generation responses of about 0.2 and 0.25 times that of KH2PO4.  相似文献   

15.
The FT IR and FT Raman spectra of Co(en)3Al3P4O16 · 3H2O (compound I) and [NH4]3[Co(NH3)6]3[Al2(PO4)4]2 · 2H2O (compound II) are recorded and analysed based on the vibrations of Co(en)33+, Co(NH3)63+, NH4+, Al---O---P, PO3, PO2 and H2O. The observed splitting of bands indicate that the site symmetry and correlation field effects are appreciable in both the compounds. In compound I, the overtone of CH2 deformation Fermi resonates with its symmetric stretching vibration. The NH4 ion in compound II is not free to rotate in the crystalline lattice. Hydrogen bonding of different groups is also discussed.  相似文献   

16.
One-dimensional Co(dien)2(VO3)3·(H2O) was prepared from the hydrothermal reaction of NH4VO3, Co2O3, diethylenetriamine (dien) and H2O at 130 °C. The compound crystallizes in the monoclinic system, space group P21/c with a=16.1581(6) Å, b=8.7006(3) Å, c=13.9893(4) Å, β=103.1483(11)°, V=1915.13(11) Å3, Z=4, and R1=0.0268 for 3060 observed reflections. Single crystal X-ray diffraction revealed that the structure is composed of infinite one-dimensional chains formed by corner-sharing VO4 tetrahedra with Co(dien)3+ complex cations and crystallization water molecules occupying the interchain positions, which are held together to a three-dimensional network via extensive hydrogen-bonding interactions. The compound, with a new zig-zag conformation of metavanadate chains, is the first example of vanadium oxides incorporating trivalent transition metal coordination groups. Other characterizations by elemental analysis, IR and thermal analysis are also described.  相似文献   

17.
Crystals of the rhenium cluster complex (H3O)4[(C2H5)4N]6[Th2Cl4(H2O)12O]3[Re4Se4(CN)12]4 are obtained in an acidic (HCl) aqueous solution by the reaction of cluster salt K4[Re4Se4(CN)12]·6H2O with ThCl4 and (C2H5)4NCl. Single crystal X-ray analysis shows that the title compound is ionic and crystallizes in the cubic crystal system (a = 22.7322(3) ?, V = 11746.93(27) ?3, Z = 2, I4 3m space group, R = 0.0350). It contains [Th2Cl4(H2O)12O]2+ cations with two thorium atoms bonded to each other through the bridging oxygen atom forming an angle of 180° in the structure.  相似文献   

18.
A novel malonate-bridged copper (II) compound of formula {[Cu4(4,4′-bpy)8(mal)2(H2O)4](ClO4)2(H2O)4(CH3OH)2}n (4,4′-bpy = 4,4′-bipyridine; mal = malonate dianion) has been prepared and structurally characterized by X-ray crystallography. This compound exhibits a novel three-dimensional network being composed of Cu-4,4′-bipyridine layers which are pillared by malonate bridge ligands. The copper(II) ions has two different coordination environment.  相似文献   

19.
为了开发较高能量密度的超级电容器,我们通过简单的溶剂热反应合成了一种三维的钴基金属有机框架(MOF)化合物([KCo7(OH)3(ip)6(H2O)4]·12H2O,Co?ip;ip=间苯二甲酸根),并考察了其作为超级电容器电极材料的性能。Co?ip电极显示出高比电容、良好的循环稳定性和优良的倍率性能。在1 mol·L^-1 KOH溶液中,电流密度为1 A·g^-1时,其最大比电容为1660 F·g^-1。在电流密度为2 A·g^-1条件下,循环3000次后,其比电容的保持率为82.7%。优异的超级电容性能可归因于Co?ip具有纳米尺寸颗粒和三维的多孔结构。  相似文献   

20.
Two new vanadium squarates have been synthesized, characterized by infrared and thermal behavior and their structures determined by single crystal X-ray diffraction. Both structures are made of discrete, binuclear vanadium entity but in 1, [V(OH)(H2O)2(C4O4)]2·2H2O the vanadium atom is trivalent and the entity is neutral while in 2, (NH4)[(VO)2(OH)(C4O4)2(H2O)3]·3H2O, the vanadium atom is tetravalent and the entity is negatively charged, balanced by the presence of one ammonium ion. Both molecular anions are bridged by two terminal μ2 squarate ligands. 1 crystallizes in the triclinic system, space group P-1, with lattice constants a=7.5112(10) Å, b=7.5603(8) Å, c=8.2185(8) Å, α=106.904(8)°, β=94.510(10)°, γ=113.984(9)° while 2 crystallizes in the monoclinic system, space group C2/c, with a=14.9340(15) Å, b=6.4900(9) Å, c=17.9590(19) Å and β=97.927(12)°. From the magnetic point of view, V(III) binuclear species show ferromagnetic interactions at low temperatures. However, no anomalies pointing to magnetic ordering are observed down to 2 K.  相似文献   

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