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1.
An Unusual System of Hydrogen Bonds in Rubidium Hydroxide Dihydrate, RbOH · 2 H2O RbOH · 2H2O was obtained by the reaction of Rb with H2O and dehydration of the resulting solution by concentrated sulfuric acid. The compound melts at 310 K. The structure was determined by X-ray single crystal methods: The H positions of H2O were found. The structure consists of a threedimensional H-bonded network of H2O molecules and OH?ions. Hydroxide ions are acceptors for four protons of four adjacent water molecules with d(O? O) = 2×2.59 Å and 2×2.82 Å. Oxygen of OH-ions is disordered over a distance of 1.27 Å. Rb has 8 H2O molecules as nearest neighbours, d(Rb? O) = 3.03 Å to 3.07 Å, OH?ions are further removed with d(Rb? O) ≥ 3.45 Å.  相似文献   

2.
The mononuclear Schiff-base copper(II) compound, [Cu(C13H9Cl2N2O)(NO3)], has been synthesized and characterized by elemental analysis and X-ray single crystal determination. The compound crystallizes in the orthorhombic, space group Cmc21 with unit cell dimensions a?=?6.713(1), b?=?22.147(3), c?=?9.976(1)?Å?, M r?=?405.67, V?=?1483.2(3)?Å3, Z?=?4, R 1?=?0.0568 and wR 2?=?0.1331. X-ray structure determination revealed that the compound possesses crystallographic mirror symmetry. The CuII ion in the compound is five-coordinate in a distorted trigonal bipyramid with one O and two N atoms of the Schiff-base and by two O atoms of the nitrate anion. In the crystal structure, the molecules are linked via intermoleclular C?H?···?O non-classical hydrogen bonds, forming a two-dimensional network. Density functional theory (DFT) and Hartree-Fock (HF) calculations of the structure, atomic charge distribution and natural bond orbital analyses have been performed. The calculated results show that the CuII ion mainly adopts spd2 hybridization and forms five bonds with the NNO donor set of the Schiff-base ligand and with two O atoms of nitrate from four orientations. The coordinate stabilization energies show that the Schiff-base copper(II) compound is very stable.  相似文献   

3.
The synthesis, crystal structure and properties of a novel ternary inclusion compound formed by protonated bis(quinuclidine) inserted in a urea–chloride anionic host, urea5[quinuclidine2H]+Cl- (1), are reported. In the host structure each urea molecule interacts with adjacent urea molecules via N-H ?O hydrogen bonds forming a channel arrangement. Each hexagonal channel is linked through halide ions by N-H ?Cl hydrogen bonds forming a bichannel-like structure. The channel width of the host (14.32?Å) is one of the largest known for a urea host derivative. The compound may be described as a commensurate species, c g/c h=0.98. Conductivity determined for 1 at room temperature is 4.00?×?10-6 (Ω?cm)-1, and it increases with temperature to 3.33?×?10-4 (Ω?cm)-1 at 77°C. Aspects of the thermal stability of the product are discussed.  相似文献   

4.
On Heterocyclic Systems Containing Tin. VIII. 2-Chloro-2-phenyl-1,3,6-trithia-2-stannocane, Crystal Structure and Vibrational Spectra The crystal structure of the title compound has been determined and refined until R = 0.040. The coordination around tin is trigonal bipyramidal (equatorial ligands 2 × S and Ph; axial ligands Sn? Cl 245.3(2) and 1,5-transannular Sn…?S 280.6(2) pm). The eight-membered ring has boat-chair conformation. The vibrational spectra of the title compound and of five analogues with donor O or S and substitution Cl, Ph are given and discussed. The three compounds with donor S have nearly identical aliphatic ring modes (3 × boat-chair conformation), whereas these modes exhibit a conformational change for the case of donor O in the series Cl2, Ph2, ClPh substituted tin. The stretching vibrations of the coordination polyhedron ClnSnS2 are in the range 400 to 340 cm?1. The strong 1,5-transannular Sn…?O or Sn…?S interactions in the cases of Cl substituted Sn are correlated with strong and broad transitions in the range 330 to 280 cm?1; an extended distance of 5 pm is in correspondence with an approximate decrease of energy by 40 cm?1.  相似文献   

5.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

6.
In an attempt to crystallize Ce[ReO4]4 · xH2O from aqueous solutions of equimolar amounts of Ce[SO4]2 and Ba[ReO4]2 via salt‐metathesis the serendipitous formation of colorless, transparent, rod‐shaped single crystals of CaNa[ReO4]3 was observed as a result of calcium and sodium impurities within the improperly deionized water used. Structure analysis by X‐ray diffraction lead to the conclusion that the title compound crystallizes in the ThCd[MoO4]3 structure type with the hexagonal space group P63/m and the lattice parameters a = 991.74(6) pm, c = 636.53(4) pm, c/a = 0.642 for Z = 2. The crystal structure contains purely oxygen surrounded and crystallographically unique cations, namely Ca2+ in tricapped trigonal prismatic (d(Ca–O) = 6 × 249 pm + 3 × 254 pm), Na+ in octahedral (d(Na–O) = 6 × 241 pm), and Re7+ in tetrahedral coordination (d(Re–O) = 171–173 pm). Furthermore, it was possible to yield an almost phase‐pure microcrystalline powder of the title compound from a melt of equimolar amounts of Na[ReO4] and Ca[ReO4]2 stemming from aquatically obtained precursors.  相似文献   

7.
The compound 2-{5-[2-(2,6-dichlorophenylamino)benzyl]-4-p-tolyl-4H-1,2,4-triazol-3-ylthio}acetate has been prepared and characterized by IR, 1H NMR, 13C NMR and mass spectra. The crystal and molecular structure were further confirmed using single crystal X-ray diffraction. The crystal structure has been found to be stabilized by intermolecular C–H···O interaction generating bifurcated hydrogen bonds whereas the C–H···N interactions generate chain of molecules. The intramolecular N–H···N hydrogen bond forms a ring with S(7) graph-set motif.  相似文献   

8.
The synthesis and spectroscopic properties of a Na complex with ligand 3-aminopyrazine-2-carboxylic acid were described. The resulting complex was characterized by elemental analysis, IR, UV-Vis, NMR spectroscopy and single crystal X-ray diffraction method. The title compound crystallizes in the triclinic system with space group . The crystalline structure of this compound consists of supramolecular architectures involving strong intramolecular N—H…O in pyrazine molecules and intermolecular O—H…N, O—H…O, and N—H…N hydrogen bonds between substituted pyrazine and water molecules.  相似文献   

9.
Abstract

In the crystal structure of the title compound C21H24N3OP · C2H5OH, there are three crystallographically independent phosphoric triamide molecules and three ethanol molecules. The environments of the nitrogen atoms are practically planar. The phosphorus atoms display a distorted tetrahedral environment; the maximum and minimum values of angles are observed for one O?P?N and one N?P?N angles, respectively. In this structure, the phosphoramide and ethanol molecules are linked by some different intermolecular O?H···O and N?H···O hydrogen bonds to form chains. The title solvated compound has been further characterized by IR and 31P{1H}, 1H and 13C NMR spectroscopy. The geometry of the nitrogen atoms in this compound is analyzed and compared with those of analogous structures deposited in the Cambridge Structural Database (CSD; Allen, Acta Cryst. 2002, B58, 380-388).  相似文献   

10.
The structure of the title compound, C3H8NO2+·C2HO4·H2O, is formed by two chiral counterparts (l ‐ and d ‐alaninium cations), semi‐oxalate anions and water molecules, with a 1:1:1 cation–anion–water ratio. The structure is compared with that of the previously known anhydrous dl ‐alaninium semi‐oxalate [Subha Nandhini, Krishnakumar & Natarajan (2001). Acta Cryst. E 57 , o666–o668] in order to investigate the role of water molecules in the crystal packing. The structure of the hydrate resembles that of anhydrous alaninium semi‐oxalate, with the water molecule incorporated into the general three‐dimensional network of hydrogen bonds where it forms four hydrogen bonds with neighbours disposed tetrahedrally about it. Although the main structural motifs in the hydrate and in the anhydrous form are topologically similar, the incorporation of water molecules in the network results in significant geometric distortion. There are several types of hydrogen bond in the crystal structure of the hydrate, two of which (O—H...O bonds between the semi‐oxalate anions and O—H...O hydrogen bonds between water and alaninium cations) are very short. Such hydrogen bonds between semi‐oxalate anions are also present in the anhydrous form of this compound. Short distances between semi‐oxalate anions in neighbouring chains in the hydrate alternate with longer ones, whereas in the anhydrous structure they are equidistant. Despite the similarity of these compounds, dehydration of the hydrate on storage is not of a single‐crystal to single‐crystal type, but gives a polycrystalline pseudomorph, preserving the crystal habit. This transformation proceeds through the formation of an intermediate compound, presumably a hemihydrate.  相似文献   

11.
The X‐ray crystal structure analysis of the title compound, C17H30O8, revealed a 4C1 conformation of the pyran­osyl ring [Cremer–Pople puckering parameters of Q = 0.568 (2) Å, θ = 5.1 (2) and ϕ = 218 (3)°]. The structure shows no deviations from the geometric parameters of pyran­oside carbohydrates. The hydroxyl groups participate in O—H⃛O hydrogen bonds, forming a two‐dimensional pattern [O⃛O = 2.811 (3) and 2.995 (3) Å].  相似文献   

12.
LI  Ping  LIU  Zhihong 《中国化学》2009,27(11):2183-2189
Two novel organic base templated nonmetal borates [(CH3)2NH2]2[B5O6(OH)4]2·[HCON(CH3)2] ( ? ) and [NH3CH2CH2NH3]2[B14O20(OH)6] ( II ) have been synthesized under hydrothermal conditions, and characterized by elemental analyses, FT‐IR spectroscopy, X‐ray diffraction, and TG‐DTA. Their crystal structures were determined from single crystal X‐ray diffraction. The crystal structure of compound I is characterized by forming a 3D supramolecular structure with large channels along axes b and c through O? H···O hydrogen‐bonding among the [B5O6(OH)4]? anions. The crystal structure of compound II is characterized by forming a 3D supramolecular structure with large channels along axis a and direction [111] through O? H···O hydrogen‐bonding among the [B14O20(OH)6]4? anions. The templating organic amine cations in I and II are both obtained through in situ hydrothermal reactions, and are both located in the channels of the 3D supramolecular structure, respectively. Their thermal behavior has been also investigated.  相似文献   

13.
L-aspartic acid zinc was synthesized by a rapid and convenient method in high yield under microwave conditions, and its single crystal structure was analyzed by X-ray diffraction. The structure unit of the title compound is [Zn(L-Asp)(H2O)2]·H2O, which is a bicyclo-complex forming a spiral linear polymer via coordination bonds. The spiral linear polymers are assembled as a three-dimensional supramolecule by intermolecular hydrogen bonds. The crystal belongs to the orthorhombic crystal system, P2(1)2(1)2(1) space group, a=0.7830(3) nm, b=0.9369(4) nm, c=11.599(5) nm, α=β=γ=90.00°, V=0.8509(6) nm3, Z=4, Dc=1.955 g/cm3, F(000)=512, μ=2.289. The toxicity of the title compound is lower than that of glutamic acid zinc and zinc sulfate.  相似文献   

14.
A mixed-ligand compound, [Ni2(BPTC)(pyz)?·?2H2O] n (0.5H2O) n (BPTC?=?3,3′,4, 4′-benzophenone-tetracarboxylate, pyz?=?pyrazine), has been prepared hydrothermally by assembly of BPTC, NiCl2·6H2O and pyz. X-ray diffraction analysis of a single crystal reveals the three-dimensional framework assembled from pyz-pillared two-dimensional sheets. Three types of channels in one direction are established inside the structure. The third-order nonlinear optical (NLO) properties in DMF have been studied by Z-scan technique using an 8?ns laser at 532?nm. The results reveal that the new compound exhibits strong NLO absorption and self-focusing refractive performance (n 2?=?2.7?×?10?17?m2?W?1).  相似文献   

15.
A new Keggin arsenomolybdate based inorganic–organic hybrid compound containing complementary inorganic double helical chains, [Ag2(pyttz)3(H2O)][HAsMo12O40]·H2O (1), was successfully synthesized and characterized. Single crystal X-ray analysis reveals that compound 1 exhibits 3D supramolecular framework with (43)(44·62)(47·610·84) topology, in which the complementary double helical chains constructed by the left- and right-handed helical chains are found. In the crystal engineering point of view, the rich coordination atoms and conjugated heterocyclic rigid plane of pyttz organic ligand and the multiple twisted V-shaped coordination modes of Keggin POMs facilitate the formation of the inorganic helical structure. In addition, the title compound exhibits good photocatalytic degradation of methylene blue dye, and is very stable and easily separated from the catalytic system for reuse as well.  相似文献   

16.
The Crystal Structure of the Sodium Oxohydroxoaluminate Hydrate Na2[Al2O3(OH)2] · 1.5 H2O The crystal structure of the sodium oxohydroxoaluminate hydrate Na2[Al2O3(OH)2] ·s 1.5 H2O (up to now described as Na2O · Al2O3 · 2.5 H2O and Na2O · Al2O3 · 3 H2O, respectively) was solved. The X-ray single crystal diffraction analysis (tetragonal, space group P-421m, a = 10.522(1) Å, c = 5.330(1) Å, Z = 4) results in a polymeric layered structure, consisting of AlO3/2(OH) tetrahedral groups. Between these layers the Na+ ions are situated, which form tetrameric groups of face-linked NaO6 octahedra. The involved O2? ions are due to Al? O? Al bridges, Al? OH groups and water of crystallization. 27Al and 23Na MAS NMR investigations confirm the crystal structure analysis. The relations between the crystallization behaviour of the compound and the constitution of the aluminate anions in the corresponding sodium aluminate solution and in the solid, respectively, are discussed.  相似文献   

17.
A novel energetic microporous metal‐organic coordination polymer {[Ni(tnbpdc)(bpy)(H2O)2] · 1.5(DMF)}n ( 1 ) (tnbpdc = 2, 2′,6, 6′‐tetranitro‐4, 4′‐biphenyl dicarboxylate, bpy = 4, 4′‐bipyridine) was prepared solvothermally and characterized by elemental, IR spectroscopic, and single‐crystal X‐ray diffraction analyses. The X‐ray crystal structure of 1 revealed a rectangular‐shaped grid constructed with tnbpdc linkers and bpy linkers, with the free tunnel size estimated as 11 × 15 Å2. The thermal stability of the compound was evaluated by differential scanning calorimetry and thermogravimetric analysis. Such complexes may find application as novel heat‐resistant energetic materials.  相似文献   

18.
On Heterocyclic Systems Containing Arsenic. II1). Molecular and Crystal Structure of 5-Chloro-1-oxa-4, 6-dithia-5-arsaocane The crystal structure of the title compound has been determined from single crystal X-ray data and refined to a conventional R of 0.048. The eight-membered ring has the boat-chair conformation. PITZER and BAEYER strain are smaller than in cyclooctane and the transannular 1, 5-H…?H repulsion in cyclooctane is replaced by a stabilizing 1, 5-As…?O attraction. The coordination of the As-atom is ψ trigonal-bipyramidal with axial distances As? Cl 2.27 Å, As? O 2.45 Å and equatorial distances As? S 2.25 Å. The structure consists of 12-coordinated molecules. The crystal data of the analogous Sb compound 5-Chloro-1-oxa-4, 6-dithia-5-stibaocane are given.  相似文献   

19.
IntroductionMolecularpolymerwithonedimensionalormultidimen sionalstructureassemblingthroughhydrogenbondsisanim portantresearchcontentinthesupramolecularchemistryandcrystalenginnering .1,2 Withthedevelopmentofnewtypefunctionalmaterialssuchasmolecularmagnetic ,selectedcatalysis ,reversiblecatalysis ,reversiblehost guestmolecular(ion)exchangeetc.,3themoleculardesignandsynthesishavealreadyattractedconsiderableattentioninsupramolecu larsystem .Thesupramolecularcomplexesandorganiccom poundscontainin…  相似文献   

20.
Two new “butterfly‐shaped” pentanuclear dysprosium(III) clusters, [Dy53‐OH)3(opch)6(H2O)3] ? 3 MeOH ? 9 H2O ( 1 ) and [Dy53‐OH)3(Hopch)2(opch)4(MeOH)(H2O)2] ? (ClO4)2 ? 6 MeOH ? 4 H2O ( 2 ), which were based on the heterodonor‐chelating ligand o‐vanillin pyrazine acylhydrazone (H2opch), have been successfully synthesized by applying different reaction conditions. Single‐crystal X‐ray diffraction analysis revealed that the butterfly‐shaped cores in both compounds were comparable. However, their magnetic properties were drastically different. Indeed, compound 1 showed dual slow‐relaxation processes with a transition between them that corresponded to energy gaps (Δ) of 8.1 and 37.9 K and pre‐exponential factors (τ0) of 1.7×10?5 and 9.7×10?8 s for the low‐ and high‐temperature domains, respectively, whilst only a single relaxation process was noted for compound 2 (Δ=197 K, τ0=3.2×10?9 s). These significant disparities are most likely due to the versatile coordination of the H2opch ligands with particular keto–enol tautomerism, which alters the strength of the local crystal field and, hence, the nature or direction of the easy axes of anisotropic dysprosium ions.  相似文献   

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