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1.
《结构化学》1989,(3)
<正> C12H22O4Eu(NO3)3,Mr=568. 28,monoclinic, P21/n,a=7. 980(1) ,6= 17.226(2), c=14. 460(3) A,B=100.15(1) , V= 1956. 6A3,Z=4,Dc=1.929 g/cm3,F(000) = 1128. The structure was sieved by direct methods and Fourier synthesis, and refined by block-diagonal and full matrix least-squares method to a final R of 0. 055 for 2568 independent reflections of I>3a(I). The ten donor oxygen atoms in the crowm ether and NO3 groups are coordinated to central metal ion Eu(III) forming an irregular coordination polyhedron. The Eu(III) ion is out of the ether oxygen plane and the three nitrate groups are bidentately coordinated to the Eu (III) on the opposite side of the polyether. The average bond lengths of Eu-O(NO3) and Eu-O(ether) are 2. 491A and 2. 558A ,respectively. 相似文献
2.
The title compound crystallizes in the space group C_(2h)~5-P2_1/n with unit cell constantsa=10.938 A, b=19.189 A, c=13.384 A and β=105.09°. Intensities of 4022 independent reflec-tions were collected with four-circle diffractometer using MoKa radiation. After reduction fordiffractometer data, we derived first the position parameters of all the V atoms by directmethod using SHELXTL program. The coordinates of all the non-hydrogen and hydrogenatoms were obtained from successive Fourier and difference sytheses. The block-diagonalleast-squares refinement for all atoms gave a final discrepancy weighted factor R_w=0.050. The result of structure analysis shows that four protons of each decavanadic acid arecaptured by the nitrogen atoms involved in the azepine molecules which are condensation pro-ducts of ethylenediamine with acetylaceton. In crystal, the isopoly-decavanadate anion, 7-member heterocyclic azepium and the crystal water are linked together by ionic forces andhydrogen bonding and the chemical content within a unit cell has been identified as 2[H_2V_(10)O_(28)]~(-4)·8[C_7N_2H_(13)]~( 1)·12H_2O. 相似文献
3.
《结构化学》1989,(2)
<正> BaGa4,tetragonal space group I4/mmm with lattice parameters a=b=4.5650(8), c=10.786(2)A, V=224.77(7)A3,Dc=6.15 gcm-3,and Z=2,λ(MoKα)=0.71069A,μ=335.93cm-1,F(OOO) =360. The final R = 0.045, Rw=0.069.The distribution of valence electrons in crystal Ba6a4 is described and a suggestion that two different types of gallium atoms form covalent bonds by utilizing sp3 and dsp3 hybrid orbitals respectively is proposed. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(1-2):51-59
Abstract The title complexes, diaquadi(2,2″-bipyridine)di(dichloroacetato)lanthanide(III) monodichloroacetato [Ln(CHCl2COO)2(2,2′-bipy)2(H2O)2]+(CHCl2COO)?(Ln = Dy, Ho, Tm, Er, Yb], were obtained and characterized. [Er(CHCl2COO)2(2,2′-bipy)2(H2O)2]+(CHCl2COO)? crystallizes in the mooclinic space group P21/n with Z = 4. Cell dimensions are a = 15.886(9), b = 13.758(2), c = 16.343(4)Å, β = 113.31(3)°, and the structure was refined to an R of 0.049 for 3415 observed reflections. The Er(III) ion exhibits a distorted, square antiprismatic configuration. Four N atoms of 2,2′-bipy and four O atoms from two dichloroacetato and two water ligands are coordinated. One dichloroacetato group lies outside the polyhedron and is connected with water ligands by hydrogen bonds. 相似文献
5.
《结构化学》1989,(1)
<正> C14H10N2,Mr =206.24, space group P21/n, a =5.861(3), b =10.230 (5), c =17.440(11) A,β=92.07(5)°,V= 1045(1) A3,Z=4, Dx=1.31 g.cm-3, MoKa radiation,u=0.73 cm-1,F(000)=432,R=0.063 for 1054 observed reflections. 2-Phenylquinoxaline molecule is approximately planar. The dihedral angle between the quinoxaline ring and the substituted phenyl ring is 7.0°. The C-C bond distance connecting these two rings is 1.495(4) A. The whole molecule is a conjugation system. 相似文献
6.
《结构化学》1989,(2)
<正> MoO2(C9H5NOH)2, Mr = 396,monoclinic,space group Cc,a = 13.369 (6), b = 9.408(4), c = 13.560(3)A,°=109.65°,V=1605A3,Z= 4,Dc= 1.639 g/cm3.R=0.027 for 1372 observed reflections [I>3o(I)]. X-ray analysis showed that the coordination sphere around molybdenum atom has a distorted octahedral geometry with two terminal oxygen atoms arranged in cis-form and two oxines act as bidentate ligands connected to the molybdenum through O and N atoms.Therefore, the molecule is not as Atovmyan described that the molybdenum atom is located on two-fold axis with space group C2/c but only approxiaately C2 synmetry. 相似文献
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8.
This paper reports the crystal and molecular structure of title compound. 3978 three-dimensional independent reflections were collected by Syntex R3 four circle diffractometer. The crystal is monoclinic with space group P2_1, a=8.074(1), b=11.309(4), c=27.793(9), β=106.84°(2), Z=4. The molecular formula is Pt(C_8 H_(15)O_4N)_a Cl_2. The crystal structure was solved by Patterson method and refined by block matrix least squares refinement techniques. The final R factor is 0.039.The result of crystal structure analysis shows that Pt(Ⅱ) has a dsp~2 hybrid orbital and square coordination. Two C1 atoms are located oppositely to two diethyi-dichloride-di-L-aspartare. N atoms have sp~3 tetrahedral hybrid configurations and form the coordinate bonds with Pt(Ⅱ) atom using their lone pair electrons. By reason of molecular packing and due to the formation of inner hydrogen bonds in the complex molecule, the configuration of L-aspartic acid in the title complex is more twisted than that of L-and DL-aspartic acid 相似文献
9.
《结构化学》1991,(1)
<正> The crystal and molecular structure of the title compound was determined by single crystal X-ray diffraction. The complex crystallizes in the triclinic space group P1,a=8. 450(4),b=11. 730(3),c=14. 718(6)A ,α=104. 50(3),β=103. 71 (4),γ=69. 20(3)°,Z=4,V=1302. 4(9) A3,Dc,= 1.67g/cm3, λ(MoKa) = 0. 71069 A ,μ=30. 7/cm,F(000) = 646,Mr = 327. 6,final R=0. 037 for 2198 reflections with I<3σ(I). There are two molecules of different conformation in an asymmetric unit. Atom Ge is coordinated by three chlorine atoms and one carbon atom to form an irregular tetrahedron. 相似文献
10.
《结构化学》1986,(3)
<正> The title compound, C24H20As2(Mr=458.24), crystallizes in mono-clinic with space group P21/n and a=6.268(2), b=7.494(2), c=21.340(7)A, β= 91.027(3)°, V=1002.6 A3, Z=2, D.x=1.518gcm-3. The final value of R is 0.059 for 1619 observed reflections. The four phenyls arrange in a staggered trans-conformation around the As-As' bond. 相似文献
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12.
《结构化学》1991,(1)
<正> C_19H_18N_2S_2Fe, Mt = 394. 33, monoclinic, P2_1/c,a = 7. 726 ( 7) , b = 11. 098(1 ),c= 21. 300(6) A ,β=100. 40(7)°,V= 1796. 2 A3,Z = 4,DC = 1. 458g·cm-3;MoKa,(λ=0. 71073A),μ=10. 635cm-1,F(000) = 816,room temperature,final R=0. 098,Rw=0. 121 for 3250 unique reflections,2306 reflections with I>3σ(I). The title compound is a new Schiff base which is made by condensation of formoylferrocene, FC-CHO and S-benzyldithiocarbazate. The mean Fe-C distance is 2. 04 A. The mean C-C distances in the cyclopentadienyl rings with and without side chain are 1. 43 and 1. 38 A,respectively. Electron migration from cyclopentadienyl ring to side chain is evident. A substantial Kekule-type distortion of the phenyl ring on the side chain is indicated. 相似文献
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14.
《结构化学》1989,(1)
<正> The crystal structure of (Cyanoethyloxy-ferrocenyl)-p-fluoro-phenyl methane (Fc-C(H)OCH2CH2CN, Mr=363.23) belongs to the monoclinic spacegroup P21/c with unit cell parameters: a =9.751(3), b =18.448(4), c =9.891(4)A,β= 105.71(3)°,V= 1712.7A3,Z=4,Dc=1.409g/cm3,μ=8.930cm-1,λ=0.71073A (MoKα),R=0.05. The structure and reactivities of the title compound are compared with those of its isomer. 相似文献
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16.
SYNTHESIS AND STRUCTURE OF EUROPIUM (Ⅲ) WITH N,N'''' BISSALICYLIDENE ETHYLENEDIAMINE (H_2salen) 总被引:1,自引:0,他引:1
《结构化学》1990,(2)
<正> A europium (Ⅲ) complex with N, N' - bissalicylidene-ethylenediamine (H2salen) has the formula Eu(Hsalen)(salen)4H2O,where water molecules are in the outer sphere and do not coordinate with Eu (Ⅲ), was synthesized and structurally studied. The central atom Eu is coordinated by four nitrogen atoms and four oxygen atoms in a deltadodecahedron arrangement. The crystal is monoclinic,space group P21/a with cell constants a=16. 441(2),b=20. 599(3),c=10. 719(2) A ,β=84. 16(1)°,Z=4 and V = 3611. 5(8) A3,Dc=1. 392g/cm3.The final standard deviation R is 0. 093. 相似文献
17.
《结构化学》1987,(1)
<正> To elucidate structural relations between benzo-13-crown-4 and its similar crown compound. We determined the crystal structure of the title compound, which is a pure crown. The results of our investigation show that the dihedral angle between the planes of benzo-ring and of the O-atoms in the crown ring is 43.5°. The related distances between O atoms in benzo-13-crown-4 are 2.651 to 4.906, respectively. 相似文献
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19.
《结构化学》1984,(1)
<正> Introduction. In recent years, the di-, tetra-. hexa-nuclear mixed metal cluster compounds of tungsten have been studied. In these compounds, more stable (WO_4-nSn)~2- skeleton remains unchanged. So far the penta-, hepta- and other polynuclear cluster compounds of tungsten have not yet been found. We describe here the preparation and structure of a new pentanuclear tungstencopper mixed metal cluster compound WCu_4S_4Cl_2y_6 相似文献
20.
《结构化学》1993,(1)
<正> Ta3(Te2)6, Mr = 2074. 04, tetragonal, P4/ncc, a = 9. 204(1) A , c=20,401(8) A, V=1728. 3 A 3, Z = 4, Dc = 7. 97g/cm3, λ(MoKa) = 0. 71073 A . μ= 386, 3cm-1,F(000) = 3372, T= 296K , R= 0. 027, Rw = 0, 029 for 493 observed unique reflections. The structure is composed of infinite [TaTe4] chains along the e axis. In these chains, the Ta sequences distort in such a way that linear Ta, clusters are formed. 相似文献