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1.
Crystallography Reports - The structure and thermal properties of mesomorphic phenyl benzoate CH3–C(O)–C6H4–OC(O)–C6H4–OC9H19 (I) were studied by differential scanning...  相似文献   

2.
Crystallography Reports - For structures with a C2PO2 skeleton, a comparison of “single-and-half” phosphorus–oxygen bonds with single and double phosphorus–oxygen bonds is...  相似文献   

3.
4.
Crystallography Reports - The structure and thermal properties of azobenzene derivatives R1–C6H4–N=N–C6H4–R2, where R1/R2 = CH3COO/C2H5O (I), CH2=C(CH3)COO/C2H5 (II), or...  相似文献   

5.
The structure of the title compound has been confirmed by an X-ray diffraction analysis, and refined by full-matrix least squares. The crystals are mono-clinic:a=9.171(3),b=25.176(15)c=9.192(3) Å,=117.08(3)°,Z=4,D x =1.976g cm–3,=2.66mm¯1, space groupP21/n (No. 14). The finalR value is 5.7%. Interatomic distances and bond angles are compared with those reported in related molecules.The preferred name of this compound according to the IUPAC rules is 3-[11–2-bis(trifluoromethyl)vinylene]- 3-carbonyl-tris (-cyclopentadienyl)-triangulo-tricobalt.  相似文献   

6.
The ethylenediammonium bis tetraiodobismuthate(III) tetrahydrate salt is monoclinic with the following unit cell dimensions:a=7.476(3)Å,b=13.194(3)Å,c=13.916(9)Å, β=95.22(6)°, space groupP21 lc withZ=2. The structure consists of disordered ethylenediammonium cations, water molecules and polynuclear anions in which slightly distored [BiI6]3? octahedra sharingcis edges are interconnected into chains. The [BiI4]? anions are connected through O(W2)?H...I hydrogen bonds, so that infinite two dimensional chains parallel to thea axis with anionic period [BiI4(H2O)]? are formed in the structure. These chains are themselves interconnected by means of the O?H...I and N...O(I) bonds originating respectively from the water molecules and the ethylenediammonium entities, forming a three-dimensional network.  相似文献   

7.
Trans-NH4[WCl4(C6H7N)2]·4H2O crystallizes from a solution oftrans-(C6H7NH) [WC14(C6H7N)2] in aqueous ammonia. The compound is air sensitive and thermally unstable; space groupI41/amd (No. 141),a=18.215(5),c=14.160(3) Å, andZ=8. The structure was solved by the heavy-atom method and refined by least squares toR andR w of 0.052 and 0.053, respectively. The unit cell contains two almost unrelated parts: the NH 4 + and WC14(C6H7N) 2 are linked by electrostatic and hydrogen bonds, and the rest of the unit cell is filled with the four isolated (H2O)8 clusters ofD 2d symmetry. The O-O distances within the cluster are 2.72(2) and 2.86(2) Å; the anion is located on a symmetry center (C 2h symmetry). The W-C1 and W-N(4-methylpyridine) bonds are 2.427(6), 2.446(6), and 2.168(15) Å.  相似文献   

8.
A terbium complex associating two ligands, oxalate and glutarate, was prepared under hydrothermal conditions at 200°C by treating an aqueous suspension of terbium oxalate decahydrate with glutaric acid and guanidinium carbonate. Its structure was solved by X-ray diffraction on a single crystal. It crystallizes in the monoclinic space group P21 with lattice constants, a = 9.514(1) Å, b = 9.0681(8) Å, c = 19.702(2) Å, and = 97.90(1)°. The terbium atoms and the oxalate ligands build dense chains which are connected by one side of the carboxylic group of some glutarate ligands, thus forming a sheet at the c level 0 and 1/2. These sheets are bridged by glutarate groups. The terbium atoms are ninefold coordinate with nine oxygen atoms of the ligands or with one water molecule and eight oxygen atoms of the ligands. Each polyhedron of the terbium atoms share one edge and one face of oxygen atoms with the two neighboring ones. The oxalate ligands are bischelating and bismonodentate. The coordination scheme of glutarate differs: either they are bismonodentate from one side and chelating and monodentate from the other side or they are chelating and monodentate from both sides.  相似文献   

9.
The title mixed-ligand copper(II) complex has been synthesized and its crystal structure at room temperature solved. The crystals are monoclinic:P21/c,a=12.004(3),b=19.402(5),c=14.192(4) Å,=108.80(3)°,Z=4. The structure was solved by direct methods, and refined to anR value of 0.041 for 4457 nonzero independent reflections. The crystal structure consists of discrete [Cu(bipy) (MPhP)] units, noncoordinated MPhPH2, and H2O molecules. Each [Cu(bipy)2(MPhP)] unit involves a five coordinate CuN4O chromophore with a distorted trigonal-bipyramidal stereochemistry. The phosphate groups are linked together by short hydrogen bonds of (P)-O-H--O-P type.  相似文献   

10.
Compound (CN3H6)2[(UO2)2(C2O4)(CH3COO)4] is synthesized and characterized by IR spectroscopy and single-crystal X-ray diffraction [a = 8.5264(2) Å, b = 13.8438(4) Å, c = 10.7284(2) Å, β = 103.543(1)°, space group P21/n, Z = 2, and R = 0.0258]. The main structural units of the crystals are binuclear [(UO2)2C2O4(CH3COO)4]2? groups, which belong to the A 2 K 02 B 4 01 crystal chemical group of uranyl complexes (A = UO 2 2+ , K 02 = C2O 4 2? , and B 01 = CH3COO?). The coordination polyhedron of the uranium atom is the UO8 hexagonal bipyramid with the oxygen atoms of the uranyl ion at the axial positions. Uranium-containing groups and guanidinium cations are connected by electrostatic interactions and by the hydrogen bond system, which involves hydrogen atoms of guanidinium cations and oxygen atoms of oxalate and acetate anions. The results of the spectroscopic study of the compound agree with the X-ray diffraction data.  相似文献   

11.
The pentakis ethylenediammonium bis undecachlorodiantimonate(III) tetrahydrate salt is monoclinic with the following unit cell dimensions:a=16.271(5) Å,b=13.004(4) Å,c=13.932(4) Å, β=111.72(2)°, space groupP21/c withZ=2. The structure was solved by Patterson methods and refined to a finalR value of 0.023 for 4435 reflections withF 0>4σ(F 0). The structure shows a layer arrangement perpendicular to thea axis: planes of the [Sb2Cl11]5− bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Sb2Cl11]5− bioctahedra are connected through O−H...Cl hydrogen bonds, such that infinite chains of composition [Sb2Cl11(H2O]n 5n− are formed in the structure, parallel to the twofold axis. These chains are themselves interconnected by means of N−H...Cl and O−H...Cl bonds originating from the [NH3(CH2)2NH3]2+ entities and the water molecules, respectively, and form a threedimensional network.  相似文献   

12.
A cobalt-thiolato-phosphite complex [Co(o-SC6H4NH2){P(OMe)3}3]PF6 has been prepared and characterized by X-ray crystallography. The complex crystallizes in the triclinic space group with a = 10.590(4), b = 11.122(3), c = 13.577(5) Å, = 101.85(1), = 108.50(1), = 101.75(1)°, V = 1420.6(8) Å3, and Z = 2. The structure comprises discrete [Co(o-SC6H4NH2){P(OMe)3}3]+ cations and PF 6 anions where the metal atom is coordinated in a highly distorted square-pyramidal environment by one chelate o-SC6H4NH 2 (abt) and two P(OMe)3 ligands in the basal positions, and a third P(OMe)3 in the axial site with Co–N,, 1.847(5), Co–S, 2.166(2), Co–P, 2.157(2), 2.147(2), and 2.125(2) Å.  相似文献   

13.
[W3(O)O3Cl3(C5H5N)6]2W6O19·6C5H5N, the side product of the reaction between WCl4(C5H5N)2 and pyridine, crystallizes in the rhombohedral space groupR¯3 (No. 148), witha=14.044(1) Å,=87.70(1)°, andZ=1. The structure was solved by the heavy-atom method, and refined to the unweighted and weighted residuals of 0.068 and 0.055, respectively. The tungsten atoms define an equilateral triangle with a capping and three bridging oxygen atoms. Two pyridines in thecis position and a chlorine atom form, together with the oxygens, a distorted octahedron around the tungsten atoms; three octahedra are connected through common edges. Important bond lengths are: W-W (single bond) 2.532(1), W-O (tricapped) 2.09(1), W-O (bridging) 1.92(1) and 1.94(1), W-C1 2.424(5), and W-N (pyridine) 2.23(1) and 2.26(1) Å. In W6O 19 2– , six WO6 octahedra have one common central oxygen, twelve bridging and six terminal oxygen atoms. Corresponding W-O bond lengths are: 2.323(1) (central oxygen), from 1.90 to 1.94(1) (bridging oxygens), and 1.70(2) Å (terminal oxygens). Lattice pyridine molecules have no important contacts with either anion or cation.  相似文献   

14.
The structure of the title compound has been determined by single crystal X-ray diffraction analysis:P21/c,M r=889.9,a=15.940(1),b=23.357(2),c=18.767(2) Å,=132.62(1)°,V c=5141.6 Å3,Z=4,D x=1.150 mg m–3,F(000)=1848; finalR f=0.074 (R w=0.085). The BH 4 ligand in the complex is bidentate. A comparative study indicates that the lengths of the Ru-carbene carbon bond and other bonds to the Ru atom are determined by a combination of several factors, and not just by a purely - or -bonding interaction.  相似文献   

15.
Triethyl ammonium Salt of O,O′-bis(p-tolyl)dithiophosphate and O,O′-bis(m-tolyl)dithiophosphate have been obtained by reaction of p- and m-cresol, respectively with P2S5 in toluene and have been characterized by elemental analysis, IR, 1H and 31P NMR spectroscopy. The molecular structure of O,O′-bis(p-tolyl)dithiophosphate has been determined. Crystal data: [Et3NH]+[(4-MeC6H4O)2PS2]: Monoclinic, P21/c, a=15.2441(9) ?, b=10.415(2) ?, c=3.9726(9) ?, β=91.709(7)°, V=2217.5(1) ?−3, Z=4.Supplementary materials Additional material available from the Cambridge Crystallographic Data Centre (CCDC no. 600927 for [Et3NH]+[(4-MeC6H4O)2PS2] comprises the final atomic coordinates for all atoms, thermal parameters, and a complete listing of bond distances and angles. Copies of this information may be obtained free of charge on application to The Director, 12 Union Road, Cambridge CB2 2EZ, UK (fax: +44-1223-336033; email: deposit@ccdc.cam.ac.uk or www:http://www.ccdc.cam.ac.uk).  相似文献   

16.
The crystal structure of bis(potassium hydrogenl-malate)·malic acid, 2[K+(C4H5O5)]·C4H6O5, has been determined: C12H16K2O15, M r =1913.9, orthorhombic, space groupP212121 a=7.719(5),b=7.916(5),c=29.863(20) Å,V c=1824.7 Å3,Z=4. The structure was determined by a new application of theDirdif procedure using MoK automatic diffractometer X-ray data, and refined by full-matrix least squares toR=0.059 for 962 reflections. A question on space-group assignment and composition was resolved only after the structure had been determined. The conformation of the central carbon skeleton of all three crystallographic independent malate moieties isanti. The potassium ions are coordinated by eight oxygen atoms, forming face-sharing distorted square antiprisms.  相似文献   

17.
The N‐N dimethyl benzylammonium tetrachlorothallate (III) [C6H5CH2NH(CH3)2]TlCl4 crystallizes in the monoclinic system P21/n at room temperature with the following unit cell dimensions: a = 7.725(3) Å, b = 14.080(5) Å, c = 13.697(4) Å, β = 91.2(2)° with Z = 4. The structure shows a layer arrangement perpendicular to the b axis: planes of [TlCl4] tetrahedra alternate with planes of [C6H5CH2NH(CH3)2]+ cations. The cohesion of the atomic arrangement is ensured by hydrogen bonds N‐H…Cl. Differential scanning calorimetric and optical birefringence measurements reveals a phase transition at T = 339K. Raman spectroscopic study and dielectric measurements were performed to discuss the mechanism of the phase transition. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

18.
[Cd(C5H4O4)(OH2)2] (1), crystallizes in the monoclinic system, space groupP21/n, with lattice parametersa=7.323(2),b=16.028(6),c=7.202(2) Å, β=113.11(1)°, andZ=4. The Cd atom coordinates to seven oxygens in a monocapped trigonal antiprism fashion. The antiprisms share one vertex to form chains which run approximately parallel to thec axis. The itaconate ligands link the chains to form layers which stack along theb axis.  相似文献   

19.
Crystallography Reports - The crystal structure of 4,4'-substituted phenyl benzoate CH2=C(CH3)–COO–C6H4–COO–C6H4–O–С9Н19 has been investigated by...  相似文献   

20.
To elucidate the effect of isomorphic substitution on the kinetics of phase transitions, single crystals of (K x (NH4)1?x ) m H n (SO4)(m + n)/2 · yH2O solid solutions are grown from the K3H(SO4)2-(NH4)3H(SO4)2-H2O system, whose end members are known to undergo superprotonic phase transitions of fundamentally different kinetics. The chemical composition of the single crystals grown is determined by energy dispersive X-ray microanalysis. The thermal and optical behavior of (K,NH4)9H7(SO4)8 · H2O single crystals is studied in the temperature range 295–420 K and the crystal structure at 295 K is determined. A comparison of the results of the studies with data for crystal K9H7(SO4)8 · H2O published earlier shows that the substitution of ammonium for potassium atoms lowers the temperature of the structural phase transition by 8 K.  相似文献   

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