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1.
To get a better understanding of the growth of cadmium mercury thiocyanate (CMTC), a promising nonlinear optical crystal, we have investigated the structures of its growth solutions by using Raman spectra. It has been found that Hg(II) ions coordinate with SCN through S atoms, forming the most stable complex of [Hg(SCN)4]2‐ in the solutions while Cd(II) ions bind to SCN around Hg(II) through the other end N atom. Thereby, taking [Hg(SCN)4]2‐ anions as centers, a network structure of Cd(II)‐N‐C‐S‐Hg(II) is formed in the solutions as in the crystal lattice. It is notably that there are other complexes, mostly the Cd(SCN)n (n < 4) complexes, in the solutions. Therefore, the solution structure of CMTC is complicated, which is believed to contribute greatly to the difficulty of growing large single crystals. Based on the analysis of the solution structures, the reasonable growth units of CMTC are proposed.  相似文献   

2.
Reaction of 1,4-dimethylpyridinium chlorosulphite with anhydrous copper(II) chloride in an atmosphere of dry nitrogen yields an ionic complex containing discrete [CuCl4]2– anions and 1,4-dimethylpyridinium cations. Electronic (solid and in solution), far infrared and1H NMR spectral data predict a distortedT d structure which has been confirmed by X-ray crystallography. The crystal structure was solved by the heavy-atom method and refined by full-matrix least squares toR=0.059 for 1685 observed reflections. The [CuCl4]2– anions exhibit twofold symmetry and there are no unusual interactions with the cations. Bond lengths and angles place it in the select class of complexes with the least flattenedT d structure.  相似文献   

3.
A novel bis (dmit) complex of copper (II), [(C3H7)4N]2[Cu(dmit)2] ( 1 ), where dmit is 2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate, was prepared and structurally characterized by X‐ray single crystal diffraction. The copper (II) atom is tetracoordinated by four dmit S atoms, forming a nearly square planar arrangement. The [Cu(dmit)2]2‐ anions and the [(C3H7)4N]+ counter‐cations form a three‐dimensional solid‐state structure by C–H…S hydrogen bonds. The third‐order nonlinear optical properties of the complex were determined by picosecond Z‐scan technique at a wavelength of 1064 nm. The results indicate the compound exhibits reverse saturation absorption and self‐defocusing performance. The molecular second‐order hyperpolarizability γ is calculated to be as high as (1.8±0.2)×10‐30 esu. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

4.
Bimetallic thiocyanate complexes crystal materials belonging to ABTC structure type: ZnCd(SCN)4 and AHg(SCN)4 (A = Zn, Cd, Mn ) which are potentially useful in second harmonic generation (SHG) have been prepared. Their structural, optical and physicochemical properties are characterized by infrared spectroscopy, X‐ray powder diffraction, vis/UV/NIR spectroscopy, SHG measurements and thermal analysis. The states of crystal growth solutions are discussed in this article. The crystals belong to tetragonal system with the space group I‐4 and exhibit SHG efficiencies over one order of magnitude higher than that of Urea. Their transparency cutoffs lie in the UV region, and they possess good physicochemical stabilities.  相似文献   

5.
Morphological characteristics and twinning mechanism of ZnS crystals under hydrothermal conditions have been investigated in this paper. It was shown that under hydrothermal conditions the morphology of ZnS crystallites changes along the four‐fold axis directions, and the crystals are observed in a positive or negative tetrahedron, or in a combination of positive and negative tetrahedra depending on the growth conditions. The positive tetrahedral areas on the crystallites get larger with increase of the concentrations of OH and S2‐ in solutions, whereas the twinned crystallites of ZnS taking an elliptic shape with (111) as composition plane are easily formed in weak basic solutions. It can be found that the morphologies of ZnS crystals are in accordance with the crystallization orientations of positive or negative coordination tetrahedra ([S‐Zn4]6+, [Zn‐S4]6‐) in the crystal although, in some cases, the practical morphology could be greatly affected by growth conditions, and the twinning mechansim can be suggested based on the linkage of growth units of positive and negative coordination tetrahedra, which were formed in the solution. The present investigations further indicated that the crystal chemistry approach based on the linkage/incorporation of growth units previously proposed by us can be sucessfully applied to interpret the growth mechanisms of the crystals and to control a desirable morphology.  相似文献   

6.
Bis{2,6‐bis (hydroxymethyl) pyridine‐O,O,N} {μ‐bis(2‐hydroxymethylpyridyl) methanolate‐O,N} dicopper(II) di(propionate) (CCDC 143763) has been prepared and studied by single‐crystal X‐ray diffraction methods at 293(2) K. The crystal structure consists of dimeric complex cation, [Cu2(μ‐bhmp)2(bhmpH)2]+2 and propionate anions (bhmp ‐ 2,6‐bis(hydroxymethyl) pyridine; bhmpH ‐ 2‐(6‐hydroxymethylpyridyl) methanolate ) and propionate anions. The complex cation contains two neutral and two monodeprotonated bhmp molecules, each coordinate to one Cu(II) atom in a tridentate chelating manner, via two O atoms and N atom. The monodeprotonated bmph molecules are also tridentate coordinate via N atom and only one O atom, which serve as bridge between two CuO4N2 moieties. The propionate anions are “ fixed” to the complex by the hydrogen bonds.  相似文献   

7.
The structure of the title complexes [Cu(AFO)2(H2O)2](ClO4)2.2(AFO).2H2O (AFO = 4,5‐Diazafluoren‐9‐one)has been established by single‐crystal X‐ray diffraction. The complex crystallizes in the triclinic space group P‐1 with cell constants a = 7.659(3) Å, b = 11.066(3) Å, c = 14.203(5) Å, alpha = 75.16(3)°, β = 79.87(3)°, gamma = 85.71(3)°, Z = 1. The structure was solved by direct methods and refined to R1 = 0.0595 (wR2 = 0.1164). The X‐ray analysis reveals that a pair of AFO ligands chelate to a Cu(II) atom in an asymmetric fashion with one Cu‐N bond being much longer than the other, the Cu(II) atom is further coordinated by a pair of aqua ligands to form an elongated octahedral geometry. In the crystal of the complex, the mononuclear complex cations [Cu(AFO)2(H2O)2]2+, uncoordinated AFO molecules, lattice water molecules and perchlorate anions are assembled into 3‐D structure via hydrogen bonds and π‐π stacking interaction.  相似文献   

8.
The crystal and molecular structure of the title compound [Cd(Im)6]CO3 3H2O, where Im = imidazole, has been determined by X-ray crystallography. The crystal structure consists of discrete Cd(Im)6 2+ cations, CO3 2– anions and three uncoordinated water molecules. It crystallizes in the hexagonal system, space group P63/m, with lattice parameters a = 9.0552(l) Å, c = 21.745(l) Å, and Z = 2; The Cd(II) ion assumes centrosymmetric octahedron geometry. The bond distance of Cd–N is 2.361(l) Å. A three-dimensional intermolecular hydrogen bond network is formed between the free carbonate anions, the imidazole ligands, and the free water molecules.  相似文献   

9.
Cadmium Magnesium Tetra Thiocyanate, CdMg(SCN)4, [CMTC] belongs to bimetallic thiocyanate complexes. CMTC crystals has been grown by solution growth technique at room temperature. The morphologies of the grown crystals are identified by single crystal analysis. Also the Powder X‐ray Diffractogram of the crystal has been recorded and the various planes of reflection are identified. The title compound crystallizes under triclinic structure with lattice parameters a = 10.0976 Å, b = 7.5015 Å, c = 5.7720 Å and β = 90.2135°. The presence of magnesium and cadmium in the grown crystals were confirmed through Atomic Absorption Spectroscopy. The grown crystals are analysed qualitatively by Fourier Transform Infrared (FTIR) and Fourier Transform Raman spectral measurements. The transmittance spectrum of the crystal in the UV‐Visible region has been recorded and analysed. The dielectric measurements for the crystals were carried out in the microwave region. The thermal stabilities of the crystals were studied by using different thermal analyses like Thermo Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

10.
(C2N2H10)2Mg(HP2O7)2·2H2O, is a new inorganic organic hybrid structure. It has been synthetized using wet chemistry. Its crystal structure consists of cis- and trans-edge sharing [MgO4(H2O)2] octahedra resulting in chains, which are linked via [HP2O7] units to form [Mg(HP2O7)2(H2O)2]4− layers. The Mg2+ cations and the ethylendiammonium cations are located on centers of inversion. The ethylendiammonium cations are alternately located in the interlayer space. The cohesion of the crystal is well ensured by coulombic interactions between anions and cations and by several hydrogen bonds. The diphosphate anion shows an eclipsed conformation.  相似文献   

11.
Abstract The cadmium(II) complex [Cd(phba)2(bim)(H2O)2]n (1) (phba = 4-hydroxybenzoate, bim = 1,2-bis(imidazol-1-yl)ethane) has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in the monoclinic space group C2/c, a = 23.820(4) ?, b = 9.5331(14) ?, c = 11.1086(19) ?, β = 111.519(4)°, V = 2346.7(7) ?3, Z = 4. The coordination geometry of Cd(II) atom is distorted octahedral; it is coordinated by two nitrogen atoms from the imidazole rings of two symmetry-related bim molecules, and four oxygen atoms from two symmetry-related phba anions and two water molecules. The Cd(II) atoms are bridged by bim molecules to form a one-dimensional chain. Graphical abstract Synthesis and crystal structure of a one-dimensional chain cadmium coordination polymer bridged through 1,2-bis(imidazol-1-yl)ethane Yuping Zhang, Liyan Wang, Shouwu Wang, Baolong Li, Yong Zhang The cadmium(II) complex [Cd(phba)2(bim)(H2O)2]n (1) has been synthesized and structurally characterized by X-ray diffraction analysis. The coordination geometry of Cd(II) atom is distorted octahedral; it is coordinated by two nitrogen atoms from the imidazole rings of two symmetry-related bim ligands, and four oxygen atoms from two symmetry-related phba anions and two water molecules. The Cd(II) atoms are bridged by bim ligands to form a one-dimensional chain.  相似文献   

12.
A complex of copper(II) with the diethylenetriaminemonopripionate ligand [Cu2(4-Dtmp)2](ClO4)2 (I) is synthesized and characterized using X-ray diffraction. The crystals of compound I are monoclinic, a = 7.740(2) Å, b = 19.199(3) Å, c = 8.449(2) Å, β = 91.61(2)°, Z = 2, and space group P21/n. The structural units of crystal I are centrosymmetric dimeric cations and statistically disordered ClO 4 anions. In the cation, the copper atom is coordinated by three N atoms [mean Cu-N, 2.01(1) Å] and two O atoms [Cu-O, 2.134(6) Å and 1.958(7) Å] of the pentadentate bridging-chelate Dtmp ligand, which occupy vertices of the trigonal bipyramid. The binuclear cations are linked via centrosymmetric pairs of hydrogen bonds into ribbons aligned parallel to the a axis of the crystal. The ClO 4 anions form columns in the same direction. In the crystal, the cationic ribbons and anionic columns alternate in a chessboard fashion. __________ Translated from Kristallografiya, Vol. 50, No. 3, 2005, pp. 450–454. Original Russian Text Copyright ? 2005 by Antsyshkina, Sadikov, Poznyak, Sergienko.  相似文献   

13.
The reaction of 2,6-dimethylpyridine with SbCl3 and HCl affords the title compound, the structure of which is ascertained by X-ray diffraction. The unit cell consists of one bridged Sb2Cl82− anion and two 2,6-dimethylpyridinium cations. The trivalent antimony ion is bonded not only directly to chlorine anions, but also is coordinated with chlorine anions by secondary bonds. In the crystal, there exists infinite coordinated chains of [Sb2Cl8] n 2n anions running along the a axis, which link 2,6-dimethylpyridinium cations by N-H…Cl hydrogen bonds.  相似文献   

14.
The crystal structures consist of organoammonium cations hydrogen bonded to tetrahedral CoCl4 2– anions. In the 4-dimethylaminopyridinium salt, [(CH3)2NC5H5NH]2CoCl4, pairs of cations hydrogen bond in an asymmetric fashion to two of the chlorines in each anion. The planar cations form two sets of – stacks, first parallel to the a axis and the second parallel to the b axis. The anions lie between these two nonintersecting sets of stacks. In contrast, for the second compound, [C6H4(CH2NH3)2]CoCl4, the tetrahedral CoCl4 2– anions form layers lying parallel to the bc plane. The 1,3-di(ammoniummethyl)benzene cations crosslink adjacent anionic layers, forming a lamellar structure of alternating organic and inorganic layers.  相似文献   

15.
Single crystals of a novel nonlinear optical organometallic compound CLTC, ([(18C6)Li][Cd(SCN)3]), were grown from aqueous solutions via evaporation technique and characterized by IR spectroscopy, thermal gravimetric analysis and X‐ray single‐crystal diffraction. By X‐ray single‐crystal structural analysis it is revealed that the compound crystallized in a noncentrosymmetric space group Cmc21 of orthorhombic system with cell parameter a = 14.767(3) Å, b = 15.454(3) Å, c = 10.644(2) Å, V = 2429.0(8) Å3 and Z = 4. The thermal stability and thermal decomposition of CLTC crystal were investigated by means of thermogravimetry and differential thermal analysis. The second harmonic generation (SHG) efficiency was measured using the Kurtz and Perry powder technique. It was shown that the value of the SHG efficiency of CLCT powder was about 2 times higher than that of potassium dihydrogen phosphate (KDP). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

16.
In this article, diaquatetrakis (thiocyanato) manganese(II) mercury(II)‐N‐methyl‐2‐pyrrolidone, MnHg(SCN)4(H2O)2.2(C3H6CONCH3), (abbreviated as MMTWMP), a new organometallic nonlinear optical crystal material is reported. The structure, optical and thermal characterizations were determined by elemental analysis, infrared and Raman spectroscopy, X‐ray powder diffraction, thermogravimetric analysis, differential scanning calorimetry, special heat, SHG measurements and UV/Vis/NIR optical transmission spectra. It belongs to the tetragonal crystallographic system, with cell parameters: a = 12.1294, c = 8.2238Å, V = 1211.27Å3. Single crystals with dimensions up to 8 × 7 × 5 mm3 have been obtained. The morphology of the crystals was indexed. The MMTWMP crystal exhibits good physicochemical stability at normal temperature and pressure. Its UV transparency cutoff is 360 nm, which is shifted to the violet by 13 nm, as compared with MnHg(SCN)4 (MMTC); the optical transmission is 44.82% at 404 nm, which is by 17.46% higher than that of MMTC.  相似文献   

17.
(C3H5N2)2[Cd(C3H4N2)2Nb2O3F8]·2H2O (C3H4N2=imidazole) (1) was prepared from the hydrothermal reaction of Nb2O5, 3CdSO4·8H2O, C3H4N2, HF and H2O at 403 K, and characterized by single crystal X-ray diffraction and IR spectra. 1 crystallizes in the orthorhombic system, space group Pba2, with a=11.0192(9), b=16.8012(14), c=6.8717(6) ?, and Z=2. The crystal is made up of [Cd(C3H4N2)2Nb2O3F8]2− anions, [C3H5N2]+ complex cations and H2O molecules of crystallization. And the backbone of the compound is a one dimension coordination polymeric chain containing the anions. The complex cations and anions are linked through hydrogen bonding interactions. Co-crystallized water molecules fill in the pores and hydrogen bond to the host. Bond valence sums show that O1, O3 and F3 have much more negative charge, which are in agreement with the crystal structure that they act as bridging atoms.Supplementary material CCDC-606794 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at http://www.ccdc.cam.ac.uk/ const/retrieving.html or from the Cambridge Data Centre (CCDC), 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033 or e-mail: deposit@ccdc.cam.ac.uk.  相似文献   

18.

Abstract  

Two complexes [Cd2(dpe)3(H2O)8]·(dpe)·(hssal)2·(H2O)2 1, [Mn(dpe)2(Hpcmb)2·(H2O)2] 2, (dpe = trans-1,2-di(4-pyrindyl)ethylene; H2hssal = sulphosalicylic acid; H2pcmb = p-(carboxyl-methyloxy)-benzenecarboxylic acid) has been prepared, and was characterized by elemental analysis, FT-IR and single-crystal X-ray diffraction. Structure indicates in complex 1 that Cd(II) is a distorted octahedral coordination geometry. The hssal2− anions are localized between 2-D sheets {[Cd(dpe)2(H2O)4]2+(dpe)}n and {{[Cd(dpe)2(H2O)4]2+}n as count anions and bridge to further connect these 2-D sheets through hydrogen bond O–H···O to form 3-D structure. The complex 2 is a single molecule structure. In 2, Each Mn(II) atom is six-coordinated with a distorted octahedral coordination geometry. The single molecule units are extended into three-dimensional structure via π–π, hydrogen bonding interactions. The thermogravimetric behavior and luminescent property of complex 1 were investigated.  相似文献   

19.
Abstract The crystallization and structures of a triclinic (henceforth T) (C6H9N2)2[CdBr4] and a monoclinic (henceforth M) of (C6H9N2)2[CoBr4] are reported. The crystal packing of both solids is analyzed and compared: both contain parallel chains of cations and stacks of anions. In both T and M, each [MBr4]2− is hydrogen bonded non-symmetrically to surrounding cations in a ladder chains that run along b axis, with planar cations in both structures falling in parallel to the planes to anions. In T the cation chains are further involved in classical π···π stacking, while in M the cation chains show less significant stacking, with longer repeat distance. Index Abstract Extensive N–H···Br hydrogen bonds link both anions and cations into chains of the ladder type parallel to the crystallographic b axis. The crystal structures of bis(2-amino-5-methylpyridinium) tetrabromometallate(II): Intermolecular interactions in (C6H9N2)2[MBr4]; M = Cd and Co Rawhi Al-Far and Basem Fares Ali   相似文献   

20.
Cadmium mercury thiocyanate (CdHg(SCN)4, CMTC) and its two lewis base adducts: cadmium mercury thiocyanate dimethyl‐sulphoxide (CdHg(SCN)4(H6C2OS)2, CMTD) and cadmium mercury thiocyanate glycol monomethyl ether (CdHg(SCN)4(C3H8O2), CMTG) have been discovered as nonlinear optical (NLO) crystal materials. Their structural, optical and physicochemical properties were characterized by X‐ray powder diffraction (XRPD), infrared spectroscopy, vis/UV/NIR spectra and thermal analysis. It is discovered that their transparency cutoffs lie in the UV region and CMTD crystals possess the shortest cutoff wavelength among the three crystal materials.  相似文献   

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