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101.
CRYSTAL STRUCTURES OF Ln(o—ClC6H4CO2)3(H2O)[Ln=Tb(Ⅲ),Nd(Ⅱ)] 总被引:1,自引:0,他引:1
102.
在-90℃下用X线单晶衍射法测定了标题化合物的晶体结构。晶体属P_(421)~c〔P4/mnc〕,α=12.540(2)〔12.515(3)〕,c=17.565(5)〔17.636(7)〕A,z=2.用1672〔788〕个独立可观测反射精修结构参数得R=0.059〔0.057〕。1中的Si是4配位。Si-O=1.58A。M(M=Mo,V)是6配位,M-O=1.64-2.37A。K是7配位,K-O=2.80~3.11A。在化合物2中,PO_4是无序的,P-O=1.51A,M-O=1.63~2.47A,K是7配位,K-O=2.85~3.10A。两个晶体都是多层二维的网状结构。 相似文献
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106.
合成了稀土铁双核配合物:〔C_5H_5Fe(CO)_2〕LnCl_2·nTHF(Ln=Nd,Sm,Gd;n=1,2)和〔C_5H_5Fe(CO)_2〕〔C_5H_4(SiMe_3)〕·LnCl·nTHF(Ln=Nd,Sm,Gd;n=0,1,2)。元素分析,热分析,红外光谱和质谱分析确认了这两种配合物。红外光谱数据表明铁与稀土原子是以羰基桥连接。晶体结构分析表明〔(C_5H_5Fe(CO)_2〕Na·4THF是〔C_5H_5Fe(CO)_2〕LnCl_2·nTHF合成的中间体。 相似文献
107.
All attempts to prepare light lanthanide dicyclopeutadienyt chloride failed,due to the disproportionation reaction. The crystal complex of [(η~5-C_5H_5)_2NdCl.OC_4H_8]_2 was successfully prepared by the reaction of NdCl_3·2C_4H_8O with cyclopentadienyl sodium (molar ratio 1:1.8)in tetrahydrofuran at room temperatureThe composition of the title compound was determined by the methods of elemental analysis, infrared spectroscopy and photoelectron spectroscopy. The crystal structure of [(η~5-C_5H_5)_2NdCl·OC_4H_8]_2 was determined from single crystal X-ray diffraction. Data were collected at-60℃ under dry nitrogen atmosphere.The complex crystallizes in the monoclinic space group P2_1/c,with Z=2. Lattice parameters are: a=8.201(3), b=21.589(6),c=8.596(3),β=109.10(3)°.The structure was solved by Patterson and Fourier techniques and refined by least-squares to a final conventional R=0.0636 for 1680 reflections. There are two Nd atoms in the dimeric unit which are bridged asymmetrically by the two chlori 相似文献
108.
<正> Compound (η5-C5H5)GdCl2(THF)3 was successfully prepared from action of GdCl3 and NaC5H5 in tetrahydrofuran (THF). X-ray diffraction data were collected at low temperature (about 210K). Its crystal belongs to the monoclinic space group P 21/n with a = 7. 821(2), b = 17.068(1), c=15. 057(1)(?), β=94. 76 (2)°, V = 2003. 2(10)(?)3, Z = 4, Dc=1. 69g/cm3, F(000)=1012, Mr=509. 6. The structure was solved by heavy-atom method. Least-squares refinement converged to a final R value of 0. 050. The coordination number of the Gd atom is 8. The centre of the cyclopentadienyl, the two Cl atoms and the three oxygen atoms of THF molecules form a distorted octahedron about the Gd atom. 相似文献
109.
Self-assembly of Ag(I) nitrate, 1,3-bis(4-pyridyl)propane (bpp) and phthalic acid monopotassium salt (KHphth) in CH3OH-H2O solution produced the title complex, {[Ag(bpp)]2(Hphth)(NO3)·(H2O)2}n, which was characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum, and photoluminescent spectrum. Single-crystal X-ray analysis revealed that the complex crystallizes in a monoclinic system, space group P21/c, with a = 15.4174(5), b = 8.6398(2), c = 25.2466(8) , β = 91.072(1)o, V = 3362.34(17) 3, Z = 4, C34H37N5O9Ag2, Mr = 875.43, Dc = 1.729 g/cm3, μ = 1.228 mm-1, F(000) = 1768, the final R = 0.0749 and wR = 0.1580 for 5754 reflections with I > 2σ(I). The Ag atom is coordinated by two N atoms from two bpp molecules in an approximately linear geometry. The Ag(I) ions are linked by the bpp molecules to form one-dimensional zigzag chains propagating along the c axis. The Hphth- and nitrate counter-ions are bridged by solvent water molecules through hydrogen bonds to generate a one-dimensional chain extending along the b axis. Electrostatic interactions between cations and anions, extensive hydrogen bonds and π-π interactions are responsible for the three-dimensional supramolecular structure. In the solid state, the compound exhibits blue photoluminescence with the maximum at 436 nm upon excitation at 344 nm. 相似文献
110.
固体化合物(NH_4)_6Mo_7O_(24)·4H_2O和(PPh_3)_2CuCl与饱和液体NH_4HS反应获得桔红针状标题晶体。晶体空间群为P2_1/c,晶胞参数a=11.742(2),b=28.186(7),c=19.304(3),β=100.57(2)°,V=6280.4(?)~3,D_c=1.46g/cm~3,Z=4,F(000)=2816。在3≤2θ≤45°范围内收集到8414个独立衍射强度数据,其中3856个I≥1.5σ(I)强度数据参加结构计算。标题化合物分子是以{MoCu_3S_3Cl}类立方烷型簇为核心的分子,Mo—Cu的平均距离为2.716。 相似文献