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1.
Chemical preparation, X-ray single crystal, thermal analysis, and IR spectrometric investigation of (C4H12N)2SO4, denoted tBAS, are described. The compound crystallizes in the monoclinic system with C2/c space group. Its unit cell dimensions are a = 11.1585(5) Å, b = 6.2148(4) Å, c = 20.070(1) Å, = 102.004(4)°, V = 1361.4(1) Å3, and Z = 4. The crystal structure of tBAS can be described as a typical thick layered organization built by all the components of the structure and centered by planes z = 1/4 and 3/4. Connection in these layers are established by N—H···O hydrogen bonds. Thermal analysis shows a reversible weak phase transition.  相似文献   

2.
The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.  相似文献   

3.
The structures of anionic pyridine-2,6-dicarboxylato (pdc2–) complexes of cobalt, nickel, and copper have been studied. The stoichiometries and structures are very much dependent on whether KOH, Et4NOH, or NaOH is used in the synthesis to deprotonate the H2pdc ligand. Crystallographic results are: (1) K2[Co(pdc)2] · 7H2O, orthorhombic, Pnna, Z = 4, a = 20.637(2)Å, b = 13.480(1)Å, c = 8.200(1)Å (2) K2[Ni(pdc)2] · 7H2O, orthorhombic, Pnna, Z = 4, a = 20.648(1)Å, b = 13.375(1)Å, c = 8.2393(8)Å (3) [Co2(H2O)5(pdc)2] · 2H2O, monoclinic, P21/c, Z = 4, a = 8.3880(6)Å, b = 27.384(2)Å, c = 9.6110(8)Å, = 98.271(6)° (4) [Ni(Hpdc)2] · 3H2O, monoclinic, P21/c, Z = 4, a = 13.679(1)Å, b = 10.0450(9)Å, c = 13.767(2)Å, = 115.184(7)° (5) Na6[Co(H2O)6][Co(pdc)2]4 · 28H2O, monoclinic, P21/n, Z = 2, a = 13.363(1)Å, b = 8.437(1)Å, c = 40.689(3)Å, = 91.288(5)° (6) Na[Ni(Hpdc)(pdc)] · 11.5H2O, monoclinic, C2/m, Z = 4, a = 15.200(2)Å, b = 22.299(2)Å, c = 8.3596(7)Å, = 118.894(7)° (7) Na[Cu(Hpdc)(pdc)] · 3H2O, monoclinic, P21/n, Z = 4, a = 9.516(4)Å, b = 14.917(6)Å, c = 12.247(5)Å, = 92.00(5)°. The potassium and sodium complexes have extensive K+—H2O and Na+—H2O networks. The fact the Et4N+ ion does not appear in any of the complexes is likely due to the fact that it is incapable of forming the intricate cation—water and hydrogen-bonding networks observed in all of the other structures.  相似文献   

4.
Two vanadium(V) hydroxylamido complexes with amino acid ligands including Alanine, [VO(NH2O)2(Ala)]·2H2O, and Threonine, VO(NH2O)2(Thr), were synthesized and characterized by elemental analyses, IR spectrum, and single crystal X-ray diffraction. The two complexes are seven-coordinated with four nitrogen atoms and three oxygen atoms in pentagonal bipyramidal geometry. The different hydrogen bonds (N–H···O, O–H···O) observed in the two complexes result in the two-dimensional network structure. [VO(NH2O)2(Ala)]·2H2O belongs to monoclinic: space group P2(1)/c, with a = 21.874(13) Å, b = 8.874(5) Å, c = 15.865(9) Å, = 100.423(8)°, V = 3029(3) Å3, Z = 12, D c = 1.678 g/cm3, (MoK) = 1.002 mm–1, F (000) = 1584, and final R 1 = 0.0375, wR 2 = 0.0886 for observed reflections 1189 (IT > I> 2(I)). VO(NH2O)2(Thr) is rhombohedral: space group R-3, with a = 21.460(16) Å, b = 21.460(16) Å, c = 11.184(12) Å, = 120°, V = 4461(7) Å3, Z = 18, D c = 1.669 g/cm3, (MoK) = 1.012 mm–1, F(000) = 2304, and final R 1 = 0.0356, wR 2 = 0.0924 for observed reflections 1306 (I > 2(I)).  相似文献   

5.
The complex [Y(NO3)3(OH2)3]·(Me2-16-crown-5)·H2O has been prepared and its crystal and molecular structure determined using single crystal X-ray diffraction. The colorless crystals belong to the monoclinic space group P21/n with Z = 4. Lattice parameters are a = 10.420(1), b = 17.257(3), c = 14.646(2) Å, = 96.79(1)°, V = 2615.1(6) Å3. The yttrium(III) ion is nine-coordinate, bonded to three bidentate nitrate groups and three water molecules. The average Y–O(nitrate) and Y–O(water) distances are 2.42(3) and 2.33(1) Å, respectively. The average HO–H···O hydrogen bonded separation is 2.767Å.  相似文献   

6.
The synthesis and crystal structure of a new EDTA complex, [CaSb2(EDTA)2(H2O)8]n, are reported. This compound crystallizes in the monoclinic space group P21/n, with a = 7.132(1) Å, b = 21.893(3) Å, c = 10.891(2) Å, = 91.15(2)°. Sb(EDTA) entities are connected through carboxylate bridges to the calcium atoms resulting in layers parallel to the (101) plane. These layers are linked through a weak Sb···O bond (3.171 Å). Pyrolysis of this complex under sulfur vapor, between 400 and 800°C, leads to a mixture of the monometallic sulfides. Pyrolysis in air above 700°C allows the easy preparation of the mixed oxide CaSb2O6.  相似文献   

7.
The crystal structure of a one-dimensional ladder-shape complex [CoL(H2O)]·2H2O, (L being 1,5-diazacyclooctane-N,N-diacetate acid), has been determined by X-ray diffraction analysis: monoclinic, space group P21/c with a = 14.406(4) Å, b = 7.380(2) Å, c = 14.594(5) Å, = 112.685(2)°, M r = 341.23, V = 1431.5(8) Å3, Z = 4. The CoII center is penta-coordinated by two O atoms of the carboxylic pendant arms, two nitrogen donors of the 1,5-diazacyclooctane (DACO) moiety, and a water molecule. The coordination geometry of CoII could be described as a distorted square pyramid and the DACO backbone adopts a normal boat/chair conformation. The complex forms a one-dimensional ladder-shape structure through inter- and intra-molecular O—H···O hydrogen bonds.  相似文献   

8.
The manganese complex, (Mn2(III)(salpa)2Cl2(H2O)2], has been prepared and its structure determined using x-ray crystallography. The dimer is a di-2-alkoxo complex which is a six-coordinate manganese dimer with unsupported alkoxide bridges and a rare example of a chloride- and water-containing manganese dimer. The complex crystallizes in the monoclinic space group P21/c with a = 9.315(5), b = 11.130(4), c = 11.637(5) Å, = 104.33(3)°, V = 1169.0(9) Å3, and Z = 2. The structure comprises discrete binuclear clusters in which the metal atoms are bridged by two alkoxo oxygens of the salpa2– ligands. The Mn—O and Mn—N distances are in good agreement with those found for other manganese(III) Schiff base complexes. The Mn—Cl and Mn—O3 distances are 2.585(2) and 2.371(2) Å, respectively, and the Mn ··· Mn distance is 3.001(1) Å. In the crystal, there are two types of hydrogen bonding between the H2O molecule and the Cl atom with Cl ··· H(H2O) distance of 2.33(6) (intramolecule: –1 + x, y, –1 + z) and 2.68(6) Å (intermolecule: –1 + x, 0.5–y, –0.5 + z).  相似文献   

9.
Chemical preparation, x-ray single crystal, and thermal analysis of C6H18N2SO4·H2O (denoted DMPS) are described. The compound crystallizes in the triclinic system with P space group. Its unit cell dimensions are a = 5.826(1) Å, b = 10.014(1) Å, c = 11.221(1) Å, = 66.716(1)°, = 84.395(1)°, = 83.759(1)°, V = 596.7(1) Å3, and Z = 2. The DMPS structure is built up from inorganic chains parallel to the a axis and linked via O(W)-H···O hydrogen bonds. These chains are interconnected by organic groups. Thermal analysis reveals the presence of one water molecule in the structure and shows a reversible weak phase transition.  相似文献   

10.
The crystal structure of a unidecahydrated cocomplex between two Inosine-5-monophosphates (IMP) and one L-glutamic acid has been determined by X-ray crystallographic methods. The crystal belongs to the monoclinic space group P21 with cell dimensions a = 8.650(1), b = 21.900(1), c = 12.370(1) Å, and = 110.4°(9). This structure reveals extensive hydrogen bonding of glutamic acid to the nucleotide through direct and water-mediated interactions. The phosphate oxygens (O3B and O1B) seem to prefer nonspecific interaction with the functional sites of glutamic acid (OE2 ······O1B = 1.78 Å, NA······O3B = 2.73 Å, OH······O3B = 3.06 Å), whereas the bases prefer specific (O······N3B = 2.88 Å) binding. A solvent mediated N7A···W5···N7B hydrogen bond used for stabilization of the stacked purine bases has been observed as in other amino acid–nucleotide cocrystals. Glutamic acid occupies the same hydrophilic region in the nucleotide cocrystal as was found in glutamine–inosine monophosphate (Gln–IMP) and in serine–inosine monophosphate (Ser–IMP) complexes through substantial replacement of free and bound water molecules. This points to the dynamic hydrogen bonding nature of the water molecules and their stereochemical cooperation for the placement of amino acid through the polycoordination within the crystal.  相似文献   

11.
X-ray diffraction data from single crystals of the trimethylamine complexes of the three boron halides, BCl3, BBr3, and BI3, lead to aP21/m monoclinic cell containing two molecules for each complex. The unit cell dimensions area = 6·68(1),b = 10·247(3),c = 6·502(6) Å, =116·2(1)° (chloro);a = 6·86(1),b = 10·612(4),c = 6·737(6) Å, = 115·8(1)° (bromo);a = 6·92(2),b = 10·86(1),c = 7·147(6) Å, = 93·9(1)° (iodo). The structures were solved by three-dimensional sharpened Patterson functions and show only the chloro and bromo compounds to be isomorphous. Refinement of 662,718 and 954 observed reflexions for the chloro, bromo and iodo complexes, respectively, using anisotropic thermal parameters yielded conventionalR factors of 0·045, 0·087 and 0·054.The molecules are shown to possess a B—N dative bond, a staggered conformation, and effective 3m (C 3v) symmetry. Average C—N bond lengths are 1·52(1) Å for all three complexes. Boronhalogen bond lengths average 1·864(4), 2·04(2) and 2·28(2) Å, while B—N bond distances are 1·609(6), 1·60(2) and 1·58(3) Å, respectively, for the chloro through iodo compounds. Bond angles are approximately tetrahedral with the C—N—C angle decreasing by several degrees in the Cl Br I series.Based in part on a dissertation submitted by Patty H. Clippard to the Rackham School of Graduate Studies of the University of Michigan, January 1969 in partial fulfillment of the requirements of the Ph.D. Degree.  相似文献   

12.
The crystal and molecular structure ofcis-dicarbonyltetraphosphinechromium(O), [(CO)2(PH3)4Cr] has been determined by X-ray diffraction methods. The compound crystallizes in the monoclinic system: space groupC2/c,a = 6·968(6),b = 11·98(1),c = 12·87(1) Å, = 99·80(8) °,V= 1059(3) Å3,Z=4,D m = 1·534(5),D x = 1·531(5) gcm–3, diffraction symmetry 2/m. The structure was solved by conventional methods, and refined by least-squares techniques to an agreement factorR = 0·078. The chromium atoms lie on rotation diads, and thus the molecules must have at least the symmetry 2(C 2); they were found to have, within the limits of accuracy, the even higher symmetrymm2 (C 2v ). There are two distinct independent Cr-P distances in the molecule, the Cr-P bonds where phosphorus istrans to carbonyl [2·338(4) Å] being significantly longer than those where phosphorus istrans to phosphine [2·282(4) Å]. This difference may be attributed to a difference in the back-bonding capabilities of the two types of ligands.We wish to thank Professor Dr E. O. Fischer for his stimulating interest in this work. Our thanks are due also to the Leibniz Rechenzentrum der Bayerischen Akademie der Wissenschaften for use of their computing facilities. This work would not have been possible without a generous grant from the Deutsche Forschungsgemeinschaft which is gratefully acknowledged.  相似文献   

13.
The crystal and molecular structure of 2-{(R)-1-Hydroxy-1-[(2S)-1-tritylaziridin-2-y1] methy1}acrylate is described. Crystal data: C26H25NO3, orthorhombic, space group P212121, a = 9.6954(5), b = 13.1458(5), c = 16.7885(7) Å, V = 2139.8(2) Å3, Z = 4. The (R,S) diastereomer shows an intramolecular hydrogen bonding N···H—O under formation of a five-membered ring with N···O distance of 2.664 Å. IR, 1H NMR and 13C NMR data are discussed. The 1H NMR of the (R,S) diastereomer shows a singlet- whereas the (S,S) diastereomer exhibits a doublet-pattern for the hydroxyl proton.  相似文献   

14.
The diamagnetictrans-diene thiocyanate salt of the macrocyclic hexamethyl-1,4,8,11-tetraazacyclotetradecadienenickel(II) complex crystallizes in the triclinic system with unit cell dimensions:a = 7·334(4),b = 8·808(6),c = 21·04(2) Å; = 63·7(0·9), = 103·8(1·4), = 110·2(1·3) °; space groupP¯1;Z = 2. The positions of all 62 atoms of the formula unit C16H32N4Ni(SCN)2.H2O have been determined and refined by least-squares methods toR= 0·071 for 3536 X-ray diffractometric reflections. The optical activity of the two amine groups yields a racemic isomer. The only local symmetry element of the macrocyclic complex is the twofold rotation axis with the N-H bonds oriented on the same side of the approximate ligand plane. Both the C(CH3)2 and the imine groups are in atrans-configuration in the ring. The space group ensures that the crystal is a racemate, containing equal numbers of both enantiomers. One of the (SCN) groups is at a distance Ni-S 3·28 Å, the other one is 4·65 Å. No rotational disorder of the CH3 groups has been observed. The three C-H bonds of the CH3 groups are in approximately antiprismatic orientations with respect to the three -bonds in the case of bonding to a C(sp3) atom. The average of the C(sp3)-C(sp2) bond lengths is 1·53 Å, and the mean value for the C(sp3)-C(sp2) bonds is 1·50 Å, with 3 = 0·03 to 0·04 Å. The distances N(sp2)-C(sp3) 1·47 Å and 1·48 Å are significantly longer than the bond lengths N(sp2)=C(sp2) of 1·28 and 1·30 Å.  相似文献   

15.
N-(3-pyridil)-2-oxo-1-naphthylidenemethylamine (C16H12N2O) was studied by elemental analysis, IR, 1H NMR, and UV–visible techniques and X-ray diffraction methods. The UV–visible spectrum of the compound was investigated in solutions effect polarity. The polarity of the some solvents was modifierly the additional (CF3COOH) and [(C2H5)3N]. The compound is in tautomeric equilibrium (phenol-imine O–H···N and keto-amine O···H–N forms) in polar and nonpolar solvents. The keto-amine form is observed in basic solutions of DMSO, ethanol, chloroform, benzene, cyclohexane, and in acidic solutions of chloroform and benzene, but not in acidic solutions of DMSO and ethanol. The compound crystallizes in the monoclinic, space group P21/a with a = 7.010(5) Å, b = 13.669(4) Å, c = 12.764(4) Å, = 101.23(4)°, V = 1199.6(10) Å3, Z = 4, D c = 1.375 g/cm3, (Mo K) = 0.088 mm–1, R = 0.045 for 1658 reflections [I > 2(I)]. The title compound is not planar two Schiff base moieties A [C1–C11, O1] and B [N1, C12, C13, N2, C14, C15, C16] are inclined at an angle of 27.4(1)° reflecting mainly the twist about C12–N1 [C11–C12–N1–C13, 29.7(2)°]. There is a strong intramolecular hydrogen bond (O–H···N) of 2.529(2) Å.  相似文献   

16.
The title compound [(VO)(H2O)2(SeO3)]2[(H2pipe)SO4] was synthesized under hydrothermal condition with VOSO4, piperazidine (pipe), and SeO2, and its crystal structure was established using single-crystal X-ray diffraction method. The title compound was characterized with IRFluorescence. The crystal data: P-1 (No. 2), a = 8.633(2) Å, b= 9.223(2) Å, c= 12.508(3) Å, =109.28(3)°, =90.42(3)°, = 107.79(3)°, Mr = 644.08, V=888.5(3) Å3, Z=2, Dc = 2.407 g cm–3, =5.350 mm–1, F(000)=632. The structure of the title compound consists of an infinite neutral ladder chain, which is built up from VO6 octahedral and SeO3 pyramidal units sharing vertices, and organic salt. The biprotonized pipe (piperazidine) and SO4 2– interact with one another and the inorganic chain through strong hydrogen bonds N–H···O or O–H···O to give a 3D structure. Hydrogen bonds play a role of stabilization structure.  相似文献   

17.
The title compound (C8H10N4O2) is monoclinic, with a = 7.740(2), b = 17.044(7), c = 6.992(3) Å, = 100.60(1)°, and space group P21/c. Two O-methyl groups are coplanar with the pyrimidine ring. Whereas, the O(6)-methyl group is directed away from the imidazole ring toward the N(1) atom, the O(2)-methyl is pointed away from the N(1) atom toward the N(3) atom. Two intermolecular hydrogen bonds H(8)···N(1) and H(711)···O(2) of 2.48(2) and 2.58(3) Å make a linear arrangement of the molecules. The conformation of the O-methyl groups explains some results of thermal rearrangement of 2,6-dialkoxy-7-methylpurines and differences in alkylations of 2,4-dialkoxypyrimidines and 2,6-dialkoxy-7-methylpurines.  相似文献   

18.
1-aminocyclopentane carboxylic acid monohydrate is monoclinic: space groupP21/c,a = 11·24,b = 6·27,c = 11·22 Å and = 97·6 °. The crystal structure was solved by the symbolic addition method and refined to anR factor of 12·1%. The cyclopentane ring is disordered; one of the carbon atoms exists in two alternative sites, leading to two possible conformations both of which are of the envelope type.The authors wish to thank Professor R. Srinivasan for valuable discussions and Professor G. N. Ramachandran for his keen interest. The full-matrix least-squares refinement program used was that of Gantzel, Sparks and Trueblood, modified for the CDC 3600 computer by Zalkin, Lundgren, Liminga and Braenden. The sigma 2 search program used was that of Dr. S. T. Rao. Thanks are due to these individuals for making available their programs. This work was supported in part by Grant NB-05306 to R. Zand from the National Institute of Neurological Diseases and Stroke, National Institute of Health.  相似文献   

19.
The crystal structure of di--chloro(dicyandiamide)cadmium(II) has been determined and refined by Fourier and least-squares methods toR = 0·037 using three-dimensional X-ray data collected at room-temperature on a single-crystal automated diffractometer. Crystal data are as follows:a = 10·796(7),b = 8·933(5),c = 6·847(3) Å, = 99·9(1) °,Z = 4; space groupP21/n. The cadmium atom is surrounded by four chlorine (Cu-Cl = 2·572, 2·607, 2·630, 2·647 Å) and two nitrogen atoms (Cd-N (nitrilic) = 2·358 Å; Cd-N (guanidic) = 2·430 Å) so that the whole polyhedron appears as a slightly distorted octahedron. The chlorine atoms form bridges between adjacent metal atoms so that the coordination octahedra are linked in chains running along [001]. These chains are joined together by dicyandiamide bridges.The authors wish to thank Dr. A. Immirzi (Politecnico di Milano) for the use of his compter programmes.  相似文献   

20.
Four nickle(II) 1,5-naphthalenedisulfonate (1,5nds) complexes, namely [Ni(H2O)6] (1,5nds) (1), trans-[Ni(en)2(H2O)2](1,5nds)·2H2O (2), [Ni(tren)(H2O)2](1,5nds)·H2O (3), and [Ni(dien)2](1,5nds)·2H2O (4), where en = ethylenediamine, tren = tris(2-aminoethyl)amine, and dien = diethylenetriamine, have been synthesized and structurally characterized. Compound 1 crystallizes in space group P21/c, with a = 13.200(2) Å, b = 6.6197(10) Å, c = 9.6001(14) Å, and = 92.005(3)° compound 2 crystallizes in space group C2/c, with a = 15.698(2) Å, b = 13.006(2) Å, c = 12.845(2) Å, and = 119.262(4) Å compound 3 crystallizes in space group P , with a = 8.8971(10) Å, b = 11.5440(13) Å, c = 11.9169(14) Å, = 77.254(2)°, = 74.079(2)°, and = 82.162(2)° compound 4 crystallizes in space group P21/c, with a = 10.3600(13) Å, b = 12.5650(16) Å, c = 9.9853(12) Å, and = 103.599(2)°. Compound 1 crystallizes in a typical inorganic–organic layered structure adopted by metal naphthalenesulfonate, while compounds 24 crystallize in a hybrid inorganic–organic pattern. Unlike their Cu2+ analogue, the sulfonate does not coordinate directly to Ni2+. The hydrogen bonds formed between sulfonate and water molecules are the predominant packing forces for all structures. The inherited inversion center of the 1,5nds anion is carried into the crystal structure and results in centrosymmetric crystallization of all compounds.  相似文献   

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