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Monoclinic System (monoclinic + system)
Selected AbstractsCrystal structure of a polar nematogen 4-(trans- 4-undecylcyclohexyl) isothiocyanatobenzeneCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2007S. Biswas Abstract Crystal and molecular structures of a nematogenic compound 4-(trans- 4-undecylcyclohexyl) isothiocyanatobenzene (11CHBT) have been determined by direct methods using single crystal X-ray diffraction data. The compound (C24H37N1S1) crystallizes in the monoclinic system with the space group P21/c and Z = 4. The unit cell parameters are a = 5.5539(11) Å, b = 8.1341(10) Å, c = 51.494(5) Å, and (= 91.127(14)0. The structure was refined to Rw = 0.051. The molecule is found to be slightly bow-shaped though the alkyl chain is in all- trans conformation. The phenyl ring and the alkyl chain are planar and the cyclohexyl group is in chair conformation. The isothiocyanato groups are almost linear. Parallel imbricated mode of packing of the molecules is found in the crystalline state which is precursor to the nematic phase structure. There are many van der Waals' interactions particularly in the isothiocyanato benzene part of the molecule. Of the various associated pairs of molecules the one having anti-parallel configuration with overlaps in the isothiocyanato phenyl group probably exists in both the crystalline and the nematic phases. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Spectroscopic and crystal structure analysis of diamminebis(2,4,6-triiodophenolato-O) copper(II)CRYSTAL RESEARCH AND TECHNOLOGY, Issue 5 2006Gülsün Göka Abstract The crystal structure of [Cu(C6H2I3O)2(NH3)2] (CCDC 238896) has been determined by x-ray diffraction. This monomeric centrosymmetric Cu(II) complex crystallizes in the monoclinic system. The CuO2N2 coordination sphere is trans -planar, [Cu,O: 1.943(5) Å and Cu-N: 1.972(7)] with the fifth and sixth coordination sites occupied by I atoms from the phenoxide ions [Cu,I1: 3.3552(8) Å] to form a tetragonally elongated octahedral structure for CuO2N2I2 coordination. The complex molecules hold together in a one dimensional chain true [100] direction by intermolecular hydrogen bonds. Differantial scanning calorimeter, FTIR and magnetic susceptibility measurements were also performed in order to identify the title complex. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Hydrothermal Synthesis and Structural Characterization of the High-Valent Ruthenium-Containing Polyoxoanion [{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]10,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2008Su-Wen Chen Abstract The high-valent ruthenium-containing [{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]10, anion (1) has been synthesized by hydrothermal reaction and characterized by X-ray diffraction, IR, multinuclear (31P and 183W) NMR spectroscopy andelectrochemistry. Single-crystal analysis was carried outon Rb10[{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]·21H2O, which crystallizes in the monoclinic system, space group P21/n, with a = 11.1912(14), b = 21.9257(12), c = 38.7310(96) Å, , = 94.682(19)°, V = 9472(3) Å3, Z = 4. Polyanion 1 consists of two lacunary [,-PW11O39]7, anions connected by a linear {(HO)Ru,O,Ru(OH)}4+ unit. Each ruthenium ion achieves six-coordination through interaction with two terminal oxo ligands from the lacuna of each [PW11O39]7, anion.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] In situ Investigation of Structural Changes during Deformation and Fracture of Polymers by Synchrotron SAXS and WAXS,ADVANCED ENGINEERING MATERIALS, Issue 6 2009Konrad Schneider By simultaneous mechanical characterisation and synchrotron wide-angle x-ray scattering (WAXS) and small-angle x-ray scattering (SAXS), it is possible to characterise on-line local changes in a polymer's structure with a rather-high time and space resolution, together with the mechanical properties. In this contribution, we discuss the experimental requirements for such investigations as well as three examples. The evolution of structural features during tensile deformation of a polyethylene copolymer, as depicted by WAXS (top) and SAXS (bottom) are shown in the figure. The deformation leads to a martensitic transformation from the orthorhombic to monoclinic system and the formation of nanocavities. [source] Synthesis and crystal structure of 5-pyrazol-4,5-dihydropyrazoles derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Zhengfeng Xie A series of 1-acetyl(or phenyl)-3-aryl-5-(1-phenyl-3-methyl-5-aryloxyl-pyrazol)-4,5-dihydropyrazole derivatives have been efficiently synthesized under refluxing in glacial acetic acid with two kinds of hydrazines and five kinds of chalcones of 1-phenyl-methyl-5-phenoxyl-pyrazol-4-aldehyde. The structures were confirmed on the basis of 1H NMR, IR, MS and element analysis, and the crystal structure of the compound 4c was determined by single crystal X-ray diffraction. The compound 4c belongs to monoclinic system with space group P2(1)/n, a = 11.8779(3) nm, b = 12.0901(2) nm, c = 17.7004(4) nm, , = 90°, , = 100.05(10)°, , = 90°, Formula weight: 549.46, Triclinic V = 2502.89(9) nm3, Dc = 1.458 Mg/m3, Z = 4, F (000) = 1128. [source] The Structure of Yttrialite and Its Identification Using Laboratory and Synchrotron-Based Powder X-Ray DiffractionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2009William J. Heward A highly crystalline sample of the impurity stabilized phase y -Y2Si2O7, generally known as yttrialite, has been formed from the melt of a glass with a nominal composition of 62(SiO2),10(Al2O3),28(Y2O3) mol%. Powder X-ray diffraction patterns were collected using in-house instrumentation and the 11-BM diffractometer at the Advanced Photon Source, Argonne National Laboratory, Argonne, IL. Rietveld refinements were carried out on the patterns using two structural models. On patterns collected using in-house instrumentation the correct structure assignment was difficult to determine; however, the extremely high-quality data afforded by the 11-BM instrument showed conclusively that the sample was found to crystallize in the monoclinic system (SG=P21/m) with lattice parameters a=5.03032(6), b=8.06892(6), c=7.33620(6) Å, and ,=108.673(1). Furthermore, simulations have shown that it is likely that this structure model can be used to describe natural yttrialite or yttrialite that is formed at low temperatures, though the possibility that such materials are paracrystalline is also discussed. [source] Two caesium vanadium hydrogenphosphates with tunnelled structures: Cs2V2O3(PO4)(HPO4) and Cs2[(VO)3(HPO4)4(H2O)]·H2OACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010Romain Gautier Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs2V2O3(PO4)(HPO4), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs2[(VO)3(HPO4)4(H2O)]·H2O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO6 octahedra and PO4 tetrahedra. In (I), infinite chains of corner-sharing VO6 octahedra are connected to V2O10 dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V3O15(H2O) trimers separated by hydrogenphosphate groups. Both structures show three-dimensional frameworks with tunnels in which Cs+ cations are located. [source] Hydrogen bonding and structure of Ba2Ru2Cl10O·10H2OACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2007Sihem Boufas Dibarium ,-oxido-bis[pentachloridoruthenate(IV)] decahydrate, Ba2Ru2Cl10O·10H2O, has been prepared from ruthenium(III) chloride and barium chloride in hydrochloric acid. It crystallizes in the monoclinic system (space group C2/c). The structure consists of alternating layers of [Ru2Cl10O]4, and [Ba(H2O)7]2+ complex ions along the a direction. The O atom bonded to ruthenium occupies the 4e site, with symmetry, while the other atoms occupy general 8f sites. The overall structure is held together by O,H...O hydrogen bonds and O,H...Cl dipole,dipole interactions. [source] RbBa2(N3)5: a new ternary azideACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2006Grigori V. Vajenine Rubidium dibarium pentaazide, RbBa2(N3)5, was prepared from an aqueous solution of the binary azides at room temperature. It crystallizes in the monoclinic system (space group P2/n). Two central atoms of azide groups occupy the 2c () and 2b () positions, another azide group lies completely on a twofold axis (2f), while Rb atoms are situated in 2e (2) positions. The crystal structure of RbBa2(N3)5 can be regarded as a distorted AlB2 -type arrangement of the metal atoms, with the azide groups occupying the voids between the cations. This results in coordination numbers of 8 (Rb) and 10 (Ba). The N,N distances are in the range 1.169,(8),1.190,(5),Å, typical for the azide group. [source] A new synthetic cobalt tellurate: Co3TeO6ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2006Mats Johnsson Single crystals of tricobalt(II) tellurium(VI) hexaoxide, Co3TeO6, were synthesized via transport reactions using HCl as transporting agent. The compound crystallizes in the monoclinic system (space group C2/c). The Te atoms are positioned in 4b () and 8f positions, while the Co atoms are in 4e (2) and 8f positions. The structure consists of (100) oxygen layers packed in a hhchhc sequence, with TeVI in octahedral coordination and CoII in both octahedral and tetrahedral coordination. The structure contains face-sharing CoO6 octahedra, as well as edge-sharing CoO4 tetrahedra. Co3TeO6 is the first oxide that is isostructural with the ,-Li3MF6 family of compounds (M = Al, Cr, Ga, Ti and V). [source] In1.06Ho0.94Ge2O7: a thortveitite-type compoundACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2004Erick A. Juarez-Arellano A new indium holmium digermanate, In1.06Ho0.94Ge2O7, with a thortveitite-type structure, has been prepared as a polycrystalline powder material by high-temperature solid-state reaction. This new compound crystallizes in the monoclinic system (space group C2/c, No. 15). The structure was characterized by Rietveld refinement of powder laboratory X-ray diffraction data. The In3+ and Ho3+ cations occupy the same octahedral site, forming a hexagonal arrangement on the ab plane. In their turn, the hexagonal arrangements of (In/Ho)O6 octahedral layers are held together by sheets of isolated diortho groups comprised of double tetrahedra sharing a common vertex. In this compound, the Ge2O7 diortho groups lose the ideal D3d point symmetry and also the C2h point symmetry present in the thortveitite diortho groups. The Ge,O,Ge angle bridging the diortho groups is 160.2,(3)°, compared with 180.0° for Si,O,Si in thortveitite (Sc2Si2O7). The characteristic mirror plane in the thortveitite space group (C2/m, No. 12) is not present in this new thortveitite-type compound and the diortho groups lose the C2h point symmetry, reducing to C2. [source] In1.08Gd0.92Ge2O7: a new member of the thortveitite familyACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2002Erick-Adrian Juarez-Arellano Indium gadolinium digermanium heptaoxide, In1.08Gd0.92Ge2O7, with a thortveitite-type structure, has been prepared as a polycrystalline powder material by a high-temperature solid-state reaction. As in the mineral thortveitite, the crystal structure belongs to the monoclinic system, with space group C2/m (No. 12). The precise structural parameters were obtained by applying the Rietveld method of refinement to the X-ray powder diffraction data. This layered structure presents, on one side, a honeycomb-like arrangement of the unique octahedral site, which is occupied randomly by In and Gd atoms, and, on the other side, sheets of isolated Ge2O7 diortho-groups made up of double tetrahedra sharing a common vertex and displaying C2h point symmetry. This compound showed a remarkable photoluminescence effect when it was irradiated with the X-ray beam during the X-ray diffraction measurements, and with the , beam during the Rutherford back-scattering spectrometry experiments employed to analyze the chemical stoichiometry. [source] Rb(GaPO4)2(OH)(H2O)·H2O: a hydrated rubidium gallium phosphate analogue of GaPO4·2H2O and leucophosphiteACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2002Lionel Beitone Crystals of the title hydrated rubidium gallium phosphate, rubidium aqua-,3 -hydroxo-di-,-phosphato-digallium hydrate, were synthesized hydrothermally at 453,K under autogenous pressure. The solid crystallizes in the monoclinic system and its structure was determined from single-crystal X-ray diffraction analysis. It is similar to dihydrated gallium phosphate, GaPO4·2H2O, which is isostructural with the mineral leucophosphite. The structure is built up from a three-dimensional anionic framework composed of corner-linked octameric Ga4(PO4)4(OH)2(H2O)2 units. The Ga atom is in an octahedral coordination. Connection of the Ga4P4 species generates eight-ring channels, in which are encapsulated the Rb+ cations and water molecules. [source] Cadmium copper tetrachloride tetrahydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2000Ulrich Kortz The double salt [CuCl2(H2O)2{CdCl2}]·2H2O crystallizes in the triclinic rather than the monoclinic system as reported previously. The structure consists of sheets in the ac plane with slightly distorted octahedral CdCl6 [Cd,Cl 2.5813,(8),2.6943,(8),Å] connected by Cd,Cl,Cd bridges in the Cd equatorial plane along a, and by Cd,Cl,Cu bridges to layers of square-planar CuCl2(H2O)2 along c. There are long axial Cu,Cl interactions of 2.8623,(7),Å and additional water of hydration is hydrogen bonded to coordinated water and chloride ligands. The additional water connects the ac sheets into a three-dimensional network. Both Cd and Cu occupy different sites. The Cu,Cu and Cd,Cd distances are 3.8274,(6),Å. [source] Purification, crystallization and preliminary X-ray diffraction studies of parakeet (Psittacula krameri) haemoglobinACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 10 2009S. M. Jaimohan Birds often show efficient oxygen management in order to meet the special demands of their metabolism. However, the structural studies of avian haemoglobins (Hbs) are inadequate for complete understanding of the mechanism involved. Towards this end, purification, crystallization and preliminary X-ray diffraction studies have been carried out for parakeet Hb. Parakeet Hb was crystallized as the met form in low-salt buffered conditions after extracting haemoglobin from crude blood by microcentrifugation and purifying the sample by column chromatography. Good-quality crystals were grown from 10% PEG 3350 and a crystal diffracted to about 2.8,Å resolution. Preliminary diffraction data showed that the Hb crystal belonged to the monoclinic system (space group C2), with unit-cell parameters a = 110.68, b = 64.27, c = 56.40,Å, , = 109.35°. Matthews volume analysis indicated that the crystals contained a half-tetramer in the asymmetric unit. [source] Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the small subunit of isopropylmalate isomerase (Rv2987c) from Mycobacterium tuberculosisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2009Manikandan Karuppasamy Two C-terminally truncated variants of the small subunit of Mycobacterium tuberculosis isopropylmalate isomerase (Rv2987c; LeuD), LeuD_1-156 and LeuD_1-168, have been cloned, heterologously expressed in Escherichia coli, purified using standard chromatographic techniques and crystallized. The crystals of LeuD_1-156 belonged to the hexagonal system (space group P6122 or P6522) with up to four subunits in the asymmetric unit, whereas the crystals of LeuD_1-168 belonged to the monoclinic system (space group P21) with two subunits in the asymmetric unit. Both crystals diffracted X-rays to beyond 2.0,Å resolution and were suitable for further crystallographic analysis. [source] An Unprecedented 2D 4f-3d-5d Multimetal-Isonicotinic Acid Complex: Synthesis, Structural Characterization and Magnetic PropertiesCHINESE JOURNAL OF CHEMISTRY, Issue 9 2008Wen-Tong CHEN Abstract A novel heterometallic metal-isonicotinic acid inorganic-organic hybrid complex [Zn0.5(H2O)]{(Hg2Cl5)- [Er(C6NO2H4)3(H2O)2]}(HgCl2)·0.5CH3OH·0.5H2O (1) has been successfully synthesized via a hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a=34.165(4) Å, b=9.4692(8) Å, c=24.575(3) Å, , =115.090(5)°, V=7200(1) Å3, C18.50H21Cl7ErHg3N3O10Zn0.50, Mr=1495.25, Dc=2.759 g/cm3, T=293(2) K, µ(Mo K,) =15.954 mm,1, F(000) =5400 and R1/wR2=0.0561/0.0909 for 3157 observed reflections [I>2,(I)] and 6468 unique reflections. Complex 1 is characteristic of a novel 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layered structure constructed from the [Er(C6NO2H4)3(H2O)2] chains interconnected by the Hg2Cl5, linkers. The 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layers, mercury chloride and the lattice water molecules are held together via hydrogen bonds to form a three-dimensional framework with the methanol molecules and the hydrated zinc ions located in the cavities. The magnetic properties show that complex 1 exhibits antiferromagnetic-like interactions. [source] From 1D Polymeric Chain to Two-fold Parallel Interpenetration of (4,4) Net: Synthesis and Characterization of Two New Copper(II) Complexes Derived from Highly Polydentate Aminopolycarboxylate LigandCHINESE JOURNAL OF CHEMISTRY, Issue 7 2008Ya-Pan WU Abstract Two new copper(II) polymers, {[Cu2(egta)(bpe)(H2O)2]·H2O}n (1) and {[Cu2(egta)(bipy)(H2O)2]·5H2O}n(2), [H4egta=3,12-bis(carboxymethyl)-6,9-dioxa-3,12-diazatetradecanedioic acid, bpe=1,2-bis(4-pyridyl)ethane, bipy4,4,-bipyridyl] have been synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra and TG analysis. The structure determination reveals that both 1 and 2 crystallize in a monoclinic system, space group P21/c. Complex 1 exhibits a two-fold parallel interpenetration of (4,4) net framework consisting of 1D zigzag chains interlocked together through hydrogen bonding interaction. However, the meso-helix chains of 2 are packed to form 2D supramolecular structures. Interestingly, in 2, the host frameworks encapsulate a unique pentamer water cluster and are further connected into 1D tapes by water-water hydrogen bonding interaction. Magnetic measurements reveal that there is a weak ferromagnetic interaction between the adjacent Cu(II) ions in 1. [source] Synthesis and Structural Characterization of 1,4-Di(2-methoxyphenyl)-2,5-piperazinedioneCHINESE JOURNAL OF CHEMISTRY, Issue 5 2007Shu-Sheng Zhang Abstract A new derivative of 2,5-piperazinedione, 1,4-di(2-methoxyphenyl)-2,5-piperazinedione (I), was synthesized by the cyclocondensation reaction of N -2-methoxyphenyl chloroacetamide, and its structure was characterized by elemental analysis, IR, 1H NMR and single crystal X-ray diffraction method. The crystal belongs to monoclinic system, space group P21/c with unit cell dimensions a=0.56934(10) nm, b=1.3880(2) nm, c=1.00329(17) nm, ,=90.376(3)°, V=0.7928(2) nm3, Z=2, Dc=1.367 g·cm,3, ,=0.98 cm,1, R and wR being 0.0606 and 0.1564 respectively for 1549 unique reflections with 1247 observed reflections [I>2,(I)]. The molecule has a crystallographically imposed symmetry center. The three rings in the molecule are each coplanar with their attached groups, excluding methyl H atoms and the H atoms attached to the piperazinedione ring, while the whole molecule is not planar, with dihedral angles of 74.7(1)° between the piperazinedione and each of the two aromatic rings. The crystal structure is stabilized by van der Waals and dipole-dipole forces. [source] Synthesis and Crystal Structure of Two iso - closo 11-Vertex p -Bromobenzoate Ruthenoborane Clusters: [(PPh3)(p -BrC6H4CO2)2RuB10H8] and [(PPh3)2Ru(p -BrC6H4CO2)-(PPh3)RuB10H9]CHINESE JOURNAL OF CHEMISTRY, Issue 12 2006Qing-Liang Guo Abstract The title clusters [(PPh3)(p -BrC6H4CO2)2RuB10H8] (1) and [(PPh3)2Ru(PPh3)(p -BrC6H4CO2)RuB10H9] (2) have been prepared and characterized by elemental analysis, FT-IR, 1H, 13C NMR spectra and single-crystal X-ray diffraction analysis. The clusters crystallize in monoclinic system, space group C2/c, with a=2.569(4) nm, b=1.546(2) nm, c=1.927(3) nm, ,=95.11(2)°, Z=8, V=7.622(21) nm3, Dc=1.533 Mg/m3, F(000)=3472, S=1.009, R=0.0418, wR=0.0775 and triclinic system, space group P -1, with a=1.3142(3) nm, b=1.3761(3) nm, c=1.8503(4) nm, ,=90.445(4)°, ,=105.950(4)°, (=108.980(4)°, Z=2, V=3.0251(12) nm3, Dc=1.434 Mg/m3, F(000)=1316, S=1.007, R=0.0464, wR=0.1175, respectively for 1 and 2. In the structures, both of the clusters are based on a closo -type C2v 1:2:4:2:2 RuB10 stack with the metal occupying the unique six-connected apical position. In cluster 1, the metal center has three exo -polyhedral ligands:one triphenylphosphine and two dative oxygen atoms of p -bromobenzoates. The other oxygen atoms of two p -bromobenzoate are additionally bonded to B(2) and B(3) atoms respectively, resulting in two exo -cyclic five-membered Ru-O-C-O-B rings and engendering a symmetrical conformation. The cluster 2 is a bimetallic species in which the second ruthenium is bound to the {RuB10} center via one Ru,Ru bond and two {RuHµB} bridges resulting in one closo distorted exo -polyhedral Ru(1)- Ru(2)-B(3)-B(6) tetrahedron. [source] Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing Thioamide GroupCHINESE JOURNAL OF CHEMISTRY, Issue 7 2005Liu Fa-Qian Abstract Two compounds 2-benzoyl- N -phenyl-2-(1,2,4-triazol-1-yl)thioacetamide (1) and 2-(4-chlorobenzoyl)- N -phenyl- 2-(1,2,4-triazol-1-yl)thioacetamide (2) were synthesized from substituted acetophenone, triazole and phenyl isothiocyanate by several step reactions. The structure of compound 1 was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic system with space group P21/c, a=0.8806(2) nm, b=1.2097(2) nm,c=1.4809(3) nm, ,=105.88°, Z=4, V=1.5173(6) nm3, Dc=1.411 Mg/m3, ,=0.22 mm -1, F(000)=672, finalR1=0.040 and Rw=0.103. There is obvious potentially weak CH···N intermolecular interaction in the crystal, which stabilizes the structure. The results of biological test show that the two compounds have antifungal and plant growth regulating activities. [source] Synthesis and characterization of diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 and crystal structure of {[(CsH5CH2)2Sn(ON=CHC6H5)]2O}2CHINESE JOURNAL OF CHEMISTRY, Issue 10 2004Han-Dong Yin Abstract Diorganotin compounds ([R2Sn(ON=CHC6H5)]2O)2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3), 2-ClC6H4CH2 (4), 4-ClC6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1:1 molar ratio in refluxing anhydrous benzene or toluene. They were characterized by elemental analysis, IR, 1H NMR and 119Sn NMR spectroscopy. And two sets of 119Sn chemical shifts were observed in the 119Sn NMR spectra of these compounds, indicating the presence of two types of environment around the tin atoms. The crystal structure of compound 1 was determined by X-ray single crystal diffraction analysis. The results showed that the crystal of compound 1 belongs to a monoclinic system with space group P21/c and unit cell dimensions: ,=1.0718(9) nm, b=1.9666(17) nm, c=2.0480(17) nm, ,=96.4371(14)°, Dc=1.450 g/cm3, Z=2, F(000)=1888, V=4.290(6) nm3, ,=1.206 mm,1, R1=0.0405, wR2=0.0786. The compound 1 belongs to centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn2O2 unit in which the bridging oxygen atoms are hi-coordinated. Each bridging oxygen atom also connects with an em-cyclic tin atom. The endo - and exo -cyclic tin atoms are both five-coordinated, and have coordination geometry of distorted trigonal bipyramid. [source] Preparation, Structural Characterization and Luminescent Property of Binuclear Silver (I) Complex Formed by Benzotriazole and 1-Hydroxymethyl BenzotriazoleCHINESE JOURNAL OF CHEMISTRY, Issue 9 2002Qing-Xiang Liu Abstract Dinuclear silver (I) six-membered ring complex [Ag2 (bta)2 -(hmbta)2] (ClO4)2 (3) has been synthesized by the reaction of benzotriazole (bta) (1) and 1-hydroxymethyl benzotriazole (hmbta) (2) with Ag (CH3CN)4ClO4. The structures of compound 2 and Complex 3 have been studied by single crystal X-ray diffraction analysis. The change of luminescent intensity of 1, 2 and 3 was reported. Compound 2 crystallizes in the monoclinic system with space group P2 (1)/c, a = 0.7655 (10) nm, b = 1.0126 (14) nm, c =0.9502 (13) nm, , = 95.07 (2)°, V = 0.7337 (17) nm3 and Z = 4. Complex 3 crystallizes in the triclinic system with space group P1, a = 0.73611 (18) nm, b = 0.9152 (2) nm, c = 1.2277 (3) nm, , = 87.170 (5)°, V = 0.8221 (3) nm3 and Z = 1. The main structural feature of complex 3 is a symmetric dinuclear six-membered ring formed by two silver (I) atoms and four N-atoms from two benzotriazoles. The second structural feature of complex 3 is the ,-, stacking interaction between two adjacent molecular planes, which forms the two-dimentional layer structure. Besides, compared with 2, the luminescent intensity of complex 3 shows a remarkable enhancement. [source] Synthesis and Structure of Inclusion Complex of Cyclomaltoheptaose (,-Cyclodextrin) with m - AminophenolCHINESE JOURNAL OF CHEMISTRY, Issue 4 2002Jin-Ling Wang Abstract The supramolecular compound, ,-CD/m -aminophenol [(C42H70O35)·(C6H7ON)·(H2O)7.5·CH3OH], was synthesized and characterized by X-ray diffraction analysis. It crystallizes in monoclinic system, P21 space group, with a = 1.5122(4) nm, b=1.0335(4) nm, c=2.0915(3) nm, ,=109.58(2)°, V = 3.0798(3) nm3 and final R = 0.0598. The system belongs to "shallow inclusion" which is rarely found. In this supramolecule, the guest is located over the narrow rim of the host There are so many hydrogen bonds that they build a dense hydrogen bond net. The hydrogen-bond interactions are the main force to form the whole system and keep the stability. [source] | |||||||||||||