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1.
An X-ray diffraction study has been performed to study the crystal structure of 1,10-diazonia-18-crown-6 bis(hydrogen oxalate) [H2DA18C6]2+·2C2HO 4 - (I) and 1,10-diazonia-18-crown-6 oxalate dihydrate [H2DA18C6]2+·2C2O 4 - ·2H2O (II). Crystals I are triclinic: space group , a = 7.825, b = 7.861, c = 9.349 , = 97.28, = 110.22, = 99.12°, Z = 1. Crystals II are monoclinic: space group P2 1 /n, a = 8.783, b = 10.640, c = 10.225 , = 97.04°, Z = 2. The structures of I and II were solved by direct methods and refined by the full-matrix least-squares procedure anisotropically to R = 0.036 (I) and 0.042 (II) for all 2206 (I) and 1990 (II) unique reflections measured (CAD-4 automatic diffractometer, CuK ). In the crystal structures, the ionic complexes (salts) I and II are not individual guest–host complex molecules but are parts of complex (infinite in two directions) three-dimensional layers of H-bonded molecular anions and DA18C6 dications (and water molecules in II). In structures I and II, the centrosymmetric DA18C6 dications have different conformations: two-angle in I and four-angle in II. The unusual four-angle conformation of the DA18C6 dication was found for the first time.  相似文献   

2.
The paper describes synthesis of (nBu4N)2[RuNOCl5](I), (nBu4N)2[RuNOCl4OH](II), (nBu4N)2×[RuNOCl4OH]·6H2O (III), and (nBu4N)2[RuNOCl5]· 2(nBu4N)2[RuNOCl4(H2O)]·2H2O (IV). The complexes were studied by IR spectroscopy and powder Xray and crystal Xray analyses. The structures are built up of [RuNOCl5]2- (I, IV), [RuNOCl4OH]2- (II, III), and [RuNOCl4(H2O)]- (IV) complex anions, (nBu4N)+ cations, and crystal water molecules (III, IV). The substances are moderately soluble in water; highly soluble in polar organic solvents, such as acetone, ethanol, chloroform, methylene chloride; and almost insoluble in carbon tetrachloride and toluene. Under storage in light, the compounds decompose from the surface; in darkness I and II are stable, whereas III and IV can lose part of the crystal water.  相似文献   

3.
Singlecrystal Xray analysis was employed to study dehydrated wairakite Ca0.97Na0.06K0.03×[Al1.95Si4.04O12] with the following parameters: a = 18.260(4) , b = 18.284(4) , c = 13.432(3) , = 90.28(3)°, V = 4989(3) 3, Z = 16, space group B21/d. A comparison was carried out with the structure of the hightemperature (600°) phase, space group I41/acd. The coordination of the Ca cations increased from 4 to 4 + 1. Additional ligands were acquired from the fourmember ring of the framework upon its deformation and a pairwise countershift of the cations along the c axis. This resulted in a pseudotetragonal unit cell with a doubled volume and lowered symmetry.  相似文献   

4.
Antimony(III) fluoride complexes with compositions (NH4)3Sb4F15(I) and Cs3Sb4F15(II) are structurally characterized. Crystals Iare triclinic: a= 8.317(3) Å, b= 10.419(6) Å, c= 10.826(3) Å, = 63.71(4)°, = 73.24(3)°, = 77.42(5)°, Z= 2, calcd= 3.42 g/cm3, exp= 3.45 g/cm3, space group P , R= 0.051; crystals IIare monoclinic: a= 8.079(2) Å, b= 29.116(8) Å, c= 8.162(2) Å, = 117.08(2)°, Z= 4, calcd= 4.549 g/cm3, exp= 4.50 g/cm3, space group P21/c, R= 0.036. Structure Iis composed of SbF4E and SbF5E polyhedra combined into tetranuclear chains; crystals IIconsist of SbF4E polyhedra, two of which form a dimer Sb2F7E2, while the other two are isolated (E is the antimony lone electron pair).  相似文献   

5.
The X-ray crystal structure of 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane has been determined. The neutral ligand crystallises in the triclinic space groupP with unit cell parametersa=8.467(4),b=10.057(5),c=10.637(5) Å, =67.68(3), =75.38(4), =76.34(4)°,V=800.75 Å3 andD c=1.063 g cm–3 forZ=2.R=0.047 for 2140 unique observed (I/(I)2.0) reflections (R w=0.052). Two crystallographically independent molecules are observed. Both are centrosymmetric and adopt a mesodentate conformation. Molecule (1) is identified as the (R, S, S, R)-[trans-IV] isomer and molecule (2) as the (R, R, S, S)-[trans-III] isomer. Molecular mechanics calculations provide a basis for understanding the structural and energetic relationships between the neutral and protonated forms of this tetraazamacrocyclic ligand. Supplementary Data relating to this article have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K. as Supplementary Publication No. 82149 (13 pages).  相似文献   

6.
The formation of inclusion complexes between 4-amino-1,8-naphthalimides and cyclodextrins (CDs) was investigated. The naphthalimides used in the study were 4-amino-1,8-naphthalimide (I) and4-(2-phosphonoethylamino)-N-(2-phosphonoethyl)-1,8-naphthalimide,tetraethylester (II). The CDs employed were -CD, -CD, -CD, HP--CD, HP--CD andHP--CD (HP = hydroxypropyl). Evidence for complex formation was obtained from the changes in the fluorescence spectra of the dyes in the presence of increasing amounts of the CDs. The most striking changes were observed with HP--CD and HP--CD. Treatment of the data using Benesi–Hildebrand plotswas consistent with a 1:1 inclusion model. The determined stabilityconstants were (Keq, M-1): 106 (I:HP--CD, pH = 2.0), 193 (I:HP--CD, pH = 7.0), 113 (I:HP--CD, pH = 7.0), 155(II:HP--CD, pH = 2.0), 121 (II:HP--CD,pH = 7.0), 301 (II:HP--CD, pH = 7.0). It can beconcluded that compound I forms a more stable complex with HP--CD than with HP--CD. Compound II, on the other hand, forms a more stable complex with HP--CD than with HP--CD.  相似文献   

7.
Novel complexes of Sb(III) fluorides with cation of -aminopropionic acid (-alanine), (NH3(CH2)2COOH)SbF4 H2O (I) and (NH3(CH2)2COOH)SbF4 (II), are synthesized and their crystal structures are determined. Crystals I and II are monoclinic with a = 12.1580(5) , b = 7.4167(4) , c = 10.1540(5) , = 108.222(2)°, Z = 4, space group P21/c for (I) and a = 10.483(1) , b = 7.5906(8) , c = 9.4237(9) , = 90.548(2)°, Z = 4, space group P21/c for (II). Structures I and II are formed by -alaninium cations (C3H8NO2)+ and complex anions [SbF4] n n with polymer chain structure. Complex I also contains crystallization water molecules. In the structures of complexes I and II, the -alaninium cations have different conformation, the torsion angles C(1)C(2)C(3)N in these complexes are 174.5° and 77.0°C, respectively.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 243–247.Original Russian Text Copyright © 2005 by Udovenko, Zemnukhova, Kovaleva, Davidovich.  相似文献   

8.
The crystals of [(CH2)6N4(C3H5)]Cu2Cl3 (I), [(CH2)6N4(C3H5)]Cu2Cl3 (II), and [(CH2)6N4(C3H5)]CuCl2 (III) complexes were electrochemically synthesized (ac) from CuCl2 · 2H2O and N-allylhexamethylenetetraminium chloride in ethanol solutions at pH 6, 4.5, and 3. Their structures were determined using X-ray diffraction analysis (DARCh diffractometer, MoK radiation, /2 scan mode). Complex Icrystallizes in the monoclinic system: space group A2/a, a = 24.812(6) Å, b = 8.855(3) Å, c = 12.080(2) Å, = 89.21(3)°, and Z = 8. Complex II crystallizes in the triclinic system: space group P , a = 7.618(2) Å, b = 7.048(2) Å, c = 13.150(3) Å, = 97.50(2)°, = 92.70(2)°, = 100.74(2)°, and Z = 2. The crystals of complex III are orthorhombic: space group Pmn21, a = 7.478(2) Å, b = 8.827(2) Å, c = 9.662(3) Å, Z = 2. The organic cation in complex I acts as a tridentate ,,-ligand; that in complex II, as a bidentate ,-ligand. In complex III, the organic cation is involved in coordination with the copper(I) atom only through one nitrogen atom.  相似文献   

9.
A preparative method for the synthesis of 1,1-bis(diphenylphosphinoyl)ethanol (1) has been elaborated. In CHCl3 and MeCN solutions compound1 is associated into H-bonded dimers (-H 12 kcal mol–1). Complexes of compound1 with NdIII, CuII, and CuI nitrates have been studed. The H-bonded dimers are retained upon complexing.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 928–931, May, 1994.  相似文献   

10.
An integrated Xray diffraction study was performed on polycrystals and single crystals of three new isostructural phases with general formula Ag4A2[M(NO2)4]3 (M = Pd, Pt; A = K, Rb). Data on the crystal structure solution (CAD4 diffractometer, MoK radiation, graphite monochromator = 2–30° are presented. In one crystallographically independent [M(NO2)4]2- complex anion, the planar square coordination of the central atom is completed to 4 + 2 by two oxygen atoms at a distance of 3.02–3.12 in the other anion, it is completed to 4 + 1 + 1 by an oxygen atom at a distance of 3.12–3.30 and an Ag+ cation at a distance of 3.04–3.11 . Part of the Ag+ cations form Ag - Ag dimers with a distance of 3.03–3.07. Crystalchemical analysis of known structures containing [Pd(NO2)4]2- complex anions was performed. It has been established that in none of the cases do any of the possible limiting configurations occur.  相似文献   

11.
The crystal structures of complex antimony(III) fluorides RbSbF4 (I) and (C2N4H5)SbF4 (II) were determined. The crystals of I and II are monoclinic; for I: a = 4.628(1) Å, b = 6.167(1) Å, c = 7.922(1) Å, = 100.582(3)°, V = 222.24(7) Å3, Z = 2, (calcd.) = 4.23 g/cm3, (exp.) = 4.25 g/cm3, F(000) = 248, space group P21/m, R = 0.0395; for II: a = 4.678(1) Å, b = 7.339(4) Å, c = 10.185(1) Å, = 90.88(2)°, V = 349.6(2) Å3, Z = 2, (calcd.) = 2.69 g/cm3, (exp.) = 2.70 g/cm3, F(000) = 264, space group P21. The structure of I is formed by Rb+ cations and [SbF4] n n anionic chains composed of SbF5E octahedra with two bridging fluorine atoms. The structure of IIis formed by (C2N4H5)+ cations and isolated [SbF4] anions in which the antimony polyhedra are SbF4E trigonal bipyramids. The relationship between the crystal structures and electrophysical and biological properties of single-charged cation tetrafluoroantimonates(III) was studied.  相似文献   

12.
Complex of podand 1,2-bis(2-(o-hydroxyphenoxy)ethyloxy)ethane (L) with potassium thiocyanate, [K2(NCS)2L2] (I) was synthesized and studied using X-ray diffraction analysis: space group P , a = 7.771 Å, b = 11.711 Å, c = 11.965 Å, = 72.22°, = 79.21°, = 89.07°, Z = 1. Structure I was solved by direct method and anisotropically refined by the full-matrix least-squares method to R = 0.040 for all 4370 independent reflections (CAD4 autodiffractometer, MoK ). Structure I contains [K(NCS)L] monomers of the host–guest type united into centrosymmetrical [K2(NCS)2L2] dimers via two bridging OH groups (one group from two L podands). In the monomer, the L podand appears as though to envelope the octacoordinated K+ cation, whose the coordination polyhedron is a strongly distorted hexagonal bipyramid with all six oxygen atoms of the L podand in its base and the N atom of the SCN ligand and the O atom of one of OH group of the neighboring (in dimer) L podand at its axial vertices. Molecules of I in crystal are joined through the O–H···N hydrogen bonds to form broad infinite chains along the x-axis.  相似文献   

13.
Methyl 3-[(3,5-dimethylpyrazole-1-carbothioyl)-amino]propionate (L1) and the optically active derivative of natural monoterpene (+)-3-carene, (3bS,4aR)-3-[(3,4,4-trimethyl-3b,4,4a,5-tetrahydro-cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-1-carbothioyl)-amino]propionate (L2), are synthesized. The paramagnetic CuL1Cl2 (I) and [Cu2L2 2Cl4] (II) complexes are obtained. According to the X-ray diffraction data, in mononuclear complex I, the L1 molecule performs a bidentate-cyclic function due to the coordination of the S atom of the C=S group and the N atom of the pyrazole cycle. The CuCl2NS coordination polyhedron is a distorted tetrahedron. Two molecules of complex I form an associate due to weak Cu···S interactions. Compound II is binuclear due to the bridging function of two Cl- ions, and analogous functions of the L1 and L2 ligands. The coordination polyhedron in complex II is CuCl3NS. The eff values for compounds I and II are equal to 1.81 and 1.79 B, respectively, and are constant in the interval from 78 to 300 K, indicating that noticeable exchange interactions between unpaired electrons of the Cu2+ ions are absent. The EPR spectra of the complexes in the solid phase are examined.  相似文献   

14.
Absract—Diaqua(2.2.2-Cryptand)strontium dichloride trihydrate [Sr(2.2.2-Crypt)(H2O)2]2+ · 2Cl · 3H2O (I) was prepared and studied by X-ray diffraction. The triclinic structure of I (space group P , a = 9.152 Å, b = 10.140 Å, c = 15.219 Å, = 88.84°, = 88.19°, = 87.62°, Z = 2) was solved by the direct method and refined by full-matrix least-squares calculations in the anisotropic approximation to R = 0.050 for 4188 independent reflections (CAD4 automated diffractometer, CuK radiation). The structure contains the [Sr(2.2.2-Crypt)(H2O)2]2+ host–guest cation. The Sr2+ cation resides in the 2.2.2-cryptand cavity and is coordinated by all eight heteroatoms (6O + 2N) of the cryptand ligand and by two O atoms of water molecules. The Sr2+ coordination polyhedron (C.N. 10) is a highly distorted dibase-centered two-cap trigonal prism. The crystal structure of I contains a branched system of ion–ion (intermolecular) hydrogen bonds O(w)–H···Cl, which connect the complex cations, the Cl anions, and the crystal water molecules to form infinite thick layers parallel to the yz plane.  相似文献   

15.
The crystals of N-allylisoquinolinium chlorides of the compositions [C9H7N(C3H5)]2CuIICl4 (I), [C9H7N(C3H5)]CuICl2 · H2O (II), and [C9H7N(C3H5)]CuICl1.43Br0.57 · H2O (III) were prepared by alternating-current electrosynthesis. X-ray diffraction analysis (using diffractometer models DARCH1 for I, STOE for II, and KUMA/CCD for III, MoK radiation) showed that the crystals of I are monoclinic, space group P21/n, a = 14.91(1) Å, b = 10.41(1) Å, c = 16.90(1) Å, = 109.73(8)°, V = 2470(8) Å3, Z = 4. The crystals of isostructural compounds II and III are triclinic, space group P, Z = 2; crystals II: a = 7.2446(6) Å, b = 7.4379(6) Å, c = 12.110(1) Å, = 80.95(1)°, = 85.55(1)°, = 86.60(1)°, V = 641.8(2) Å3; crystals III: a = 7.253(2) Å, b = 7.459(4) Å, c = 12.151(5) Å, = 80.82(4)°, = 83.73(3)°, = 86.81(4)°, V = 644.6(9) Å3. The structure of I is composed of CuIICl4 2– tetrahedra and N-allylisoquinolinium cations united by C–H···Cl hydrogen bonds in corrugated layers. The crystal structures of -complexesII and III are built of [C9H7(C3H5)]2Cu2 IX4 dimers, which form layers along the c axis due to the C–H···X hydrogen bonds. An important role in the structure formation is played by water molecules, which crosslink the organometallic layers to form a three-dimensional framework through the O–H···X contacts.  相似文献   

16.
Binuclear complexes [M2Cl4(-bpym)], where M = VO2+, FeII, CoII or CuII and bpym = 2,2-bipyrimidine, and [M2(hfacac)4(-bpym)] complexes, where hfacac = hexafluoroacetylacetonate and M = FeII, NiII or CoII have been synthesized and characterized by chemical analysis, conductance measurements, i.r., electronic and e.p.r spectroscopies and by magnetic susceptibility measurements (in the 4.2–291K range). CoII and FeII are in a high spin state. [(VO)2Cl4(-bpym)] is paramagnetic, without significant interactions. [Fe2Cl4(-bpym)] shows a singular behaviour explained by an antiferromagnetic intradimer exchange and a ferromagnetic interdimer interaction. All other complexes are antiferromagnetic, with an intramolecular exchange parameter, J, varying from –3.3 cm–1 for CoII/math> to –109 cm–1 for CuII.  相似文献   

17.
The crystal and molecular structure of3 has been determined by X-ray analysis. Thecrystal data are: triclinic, space group P'1,a = 12.999(2),b = 14.114(3),c = 16.132(3) Å, = 91.62(2), = 97.71(1), = 91.38(2)°,V = 2930.6(9) Å3,Z = 2,Dm = 1.046 g cm-3.Rotational disorder has been seen in the t-butyl groups whichwere refined isotropically. Least-squares refinementbased on F2, using 4827 observedreflections with I > 2(I) and 18 restraints,led to R = 0.123. The calix is found in a coneconformation. The crown ether part of the molecule isnot in a fully extended conformation but has foldsin the chain. The calix[4]crown ether-ester exhibitsmolecular recognition properties toward alkylamines.  相似文献   

18.
The crystal structure of thallium fluoroantimonate(III) complex TlSb4F13 (I), which is isostructural to KSb4F13 (II), is determined. Crystals I are tetragonal: a = 9.634(2) Å, c = 6.590(2) Å, V = 611.7(2) Å3, Z = 2, (calcd) = 5.094 g/cm3, F(000) = 804.0, space group I4¯. The structure consists of tetrameric [Sb4F13] anions formed by SbF3 groups connected by the fluoride ion and the l+ cations.  相似文献   

19.
Crystals of [Cu(DAF)(H2O)]BF4(I) and [Cu(DAF)(ClO4)] (II) (DAF is diallyl formamide) were synthesized by an alternate-current electrochemical method, and their structures were determined (MoK radiation, 1247 and 859 independent reflections with I 2(I), R= 0.043 and 0.032 for Iand II, respectively). The complexes crystallize in space group P21/n, Z= 4. For I, a= 10.782(3) Å, b= 12.096(5) Å, c= 9.185(3) Å, = 103.62(3)°, and V= 1164.2(7) Å3; for II, a= 10.064(3) Å, b= 10.753(6) Å, c= 10.002(3) Å, = 87.52(4)°, and V= 1081.4(8) Å3. The copper atom in structures Iand IIcoordinates both C=C bonds in one DAF molecule and oxygen atom of the amide group of another DAF molecule, as well as an oxygen atom of H2O (in I) or ClO4(in II) in the axial position. The uncommon behavior of the anions in structures Iand IIis explained by their different values of Pierson hardness.  相似文献   

20.
Comparative studies of the catalytic properties and thermal stability of a copper-zinc-aluminium catalyst and its components have revealed that the catalytic activity is determined by a solid solution of copper and aluminium in zinc oxide containing OH and CO 3 2– groups in its anion skeleton. The presence of aluminium in the solid solution ensures the increase of the catalyst thermal stability in the reaction medium.
-- , , OH CO 3 2– -. .
  相似文献   

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