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1.
Three compounds ASb2(SO4)2(PO4) (A = H3O+, K, Rb) were obtained from the reactions of Sb2O3, A2CO3 (A = Li, Rb) or K2SO4 and NH4H2PO4 in H2SO4 (98 %) at 220–250 °C. Their structures were determined by single‐crystal X‐ray diffraction. All compounds crystallize in the triclinic space group P$\bar{1}$ (no.2) and are isostructural. The crystal structures consist of two‐dimensional 2[Sb2(SO4)2(PO4)] anionic layers and alkali cations, which are located between anionic layers. The anionic layers are composed of [SbO4] ψ‐trigonal bipyramids, [SbO5] ψ octahedra, [SO4] tetrahedra, and [PO4] tetrahedra. All compounds are characterized by solid state UV/Vis/NIR diffuse reflectance spectra, FT‐IR spectroscopy, and Raman spectroscopy.  相似文献   

2.
In the present work, the two‐dimensional (2D) polymer poly[[μ4‐2‐(4‐nitrobenzenesulfonamido)benzoato‐κ4O1:O1:O1′:N6]silver(I)] (AgL), [Ag(C13H9N2O6S)]n, was obtained from 2‐(4‐nitrobenzenesulfonamido)benzoic acid (HL), C13H10N2O6S. FT–IR, 1H and 13C{1H} NMR spectroscopic analyses were used to characterize both compounds. The crystal structures of HL and AgL were determined by single‐crystal X‐ray diffraction. In the structure of HL, O—H…O hydrogen bonds between neighbouring molecules result in the formation of dimers, while the silver(I) complex shows polymerization associated with the O atoms of three distinct deprotonated ligands (L?). Thus, the structure of the Ag complex can be considered as a coordination polymer consisting of a one‐dimensional linear chain, constructed by carboxylate bridging groups, running parallel to the b axis. Neighbouring polymeric chains are further bridged by Ag—C monohapto contacts, resulting in a 2D framework. Fingerprint analysis of the Hirshfeld surfaces show that O…H/H…O hydrogen bonds are responsible for the most significant contacts in the crystal packing of HL and AgL, followed by the H…H and O…C/C…O interactions. The Ag…Ag, Ag…O/O…Ag and Ag…C/C…Ag interactions in the Hirshfeld surface represent 12.1% of the total interactions in the crystal packing. Studies of the interactions of the compounds with human serum albumin (HSA) indicated that both HL and AgL interact with HSA.  相似文献   

3.
The crystal structures of six members of the homologous series with general formula [BiQX]2[AgxBi1?xQ2?2xX2x?1]N+1 (Q = S, Se; X = Cl, Br; 1/2 ≤ x ≤ 1) and N = 4, 5, or 7 were determined by single‐crystal X‐ray diffraction. The series are characterized by the parameters N and x and are denoted (N, x)P. Ag3Bi4S6Cl3 (x = 0.60) (I) , Ag3.5Bi3.5S5Br4 (x = 0.70) (II) and Ag3.65Bi3.35Se4.70Br4.30 (x = 0.73) (III) belong to (4, x)P series Ag5xBi7?5xQ12?10xX10x?3 and adopt the AgBi6S9 structure type. The (5, x)P compound Ag3.66Bi4.34S6.68Br3.32 (IV) , which corresponds to x = 0.61 in Ag6xBi8?6xS14?12xBr12x?4, crystallizes isostructurally to AgBi3S5. The compounds Ag4.56Bi5.44Se8.88Br3.12 (x = 0.57) (V) and Ag5.14Bi4.86S7.76Br4.24 (x = 0.64) (VI) , which are members of (7, x)P series Ag8xBi10?8xQ18?16xBr16x?6, adopt the Ag3Bi7S12 structure type. In the monoclinic crystal structures (space group C2/m) two kinds of layered modules alternate along [001]. Modules of type A uniformly consist of paired rods of face‐sharing monocapped trigonal prisms around Bi atoms with octahedra around mixed occupied metal positions (M = Ag/Bi) between them. Modules of type B are composed of [MZ6] octahedra, which are arranged in NaCl‐type fragments of thickness N. All structures exhibit Ag/Bi disorder in octahedrally coordinated metal positions as well as Q/X mixed occupation of some anion positions. Corresponding to their black color, all compounds are narrow‐gap semiconductors (Eg = 0.35 eV for (II) ). General characteristics of the entire class of (N, x)P compounds are gathered in a catalogue.  相似文献   

4.
The anions of the title compounds contain [Ag(SCN)4] units, with the S atoms coordinating to Ag+ in a tetrahedral arrangement. Whereas in the isolated anions of tripotassium tetra­thio­cyanatoargentate(I), K3[Ag(SCN)4], (I), all SCN? groups are bonded as terminal ligands, in tetrapotassium di‐μ‐thio­cyanato‐S:S‐bis­[dithio­cyanato­argentate(I)], K4[Ag2(SCN)6], (II), two AgS4 tetrahedra share one common edge. In poly[potassium [argentate(I)‐di‐μ‐thio­cyanato‐S:S]], K[Ag(SCN)2], (III), edge‐ and vertex‐sharing of AgS4 tetrahedra results in infinite [Ag(SCN)2]? layers.  相似文献   

5.
Synthesis and Crystal Structure of Metal(I) Hydrogen Sulfates – Ag(H3O)(HSO4)2, Ag2(HSO4)2(H2SO4), AgHSO4, and Hg2(HSO4)2 Hydrogen sulfates Ag(H3O)(HSO4)2, Ag2(HSO4)2 · (H2SO4), and AgHSO4 have been synthesized from Ag2SO4 and sulfuric acid. Hg2(HSO4)2 was obtained from metallic mercury and 96% sulfuric acid as starting materials. The compounds were characterized by X‐ray single crystal structure determination. Ag(H3O)(HSO4)2 belongs to the structure type of Na(H3O)(HSO4). The silver atom is coordinated by 6 + 2 oxygen atoms. In the structure, there are dimers and chains of hydrogen bonded HSO4 tetrahedra. Dimers and chains are connected by the H3O+ ion to form a three dimensional hydrogen network. Ag2(HSO4)2(H2SO4) crystallizes isotypic to Na2(HSO4)2(H2SO4). The coordination number of silver is 6 + 1. The structure of Ag2(HSO4)2(H2SO4) is characterized by hydrogen bonded trimers of HSO4 tetrahedra, which are further connected to chains. For the recently published structure of AgHSO4 the hydrogen bonding system was discussed. There are tetrameres and chains, connected by bifurcated hydrogen bonds. The structure of Hg2(HSO4)2 contains Hg22+ cations with Hg–Hg distance of 2.509 Å. Every mercury atom is coordinated by one oxygen atom at shorter distance (2.18 Å) and three ones at longer distances (2.57 to 3.08 Å). The HSO4 tetrahedra form zigzag chains by hydrogen bonds.  相似文献   

6.
Synthesis and Crystal Structure of K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4), and Na(HSO4)(H3PO4) Mixed hydrogen sulfate phosphates K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4) and Na(HSO4)(H3PO4) were synthesized and characterized by X‐ray single crystal analysis. In case of K2(HSO4)(H2PO4) neutron powder diffraction was used additionally. For this compound an unknown supercell was found. According to X‐ray crystal structure analysis, the compounds have the following crystal data: K2(HSO4)(H2PO4) (T = 298 K), monoclinic, space group P 21/c, a = 11.150(4) Å, b = 7.371(2) Å, c = 9.436(3) Å, β = 92.29(3)°, V = 774.9(4) Å3, Z = 4, R1 = 0.039; K4(HSO4)3(H2PO4) (T = 298 K), triclinic, space group P 1, a = 7.217(8) Å, b = 7.521(9) Å, c = 7.574(8) Å, α = 71.52(1)°, β = 88.28(1)°, γ = 86.20(1)°, V = 389.1(8)Å3, Z = 1, R1 = 0.031; Na(HSO4)(H3PO4) (T = 298 K), monoclinic, space group P 21, a = 5.449(1) Å, b = 6.832(1) Å, c = 8.718(2) Å, β = 95.88(3)°, V = 322.8(1) Å3, Z = 2, R1 = 0,032. The metal atoms are coordinated by 8 or 9 oxygen atoms. The structure of K2(HSO4)(H2PO4) is characterized by hydrogen bonded chains of mixed HnS/PO4 tetrahedra. In the structure of K4(HSO4)3(H2PO4), there are dimers of HnS/PO4 tetrahedra, which are further connected to chains. Additional HSO4 tetrahedra are linked to these chains. In the structure of Na(HSO4)(H3PO4) the HSO4 tetrahedra and H3PO4 molecules form layers by hydrogen bonds.  相似文献   

7.
New Thiophosphates: The Compounds Li6Ln3(PS4)5 (Ln: Y, Gd, Dy, Yb, Lu) and Ag3Y(PS4)2 The new thiophosphates Li6Ln3(PS4)5 (Ln: Y, Gd, Dy, Yb, Lu) were synthesized by heating mixtures of Ln, P, S, and Li2S4 at 900 °C (100 h) and they were investigated by single crystal X‐ray methods. The compounds with Ln = Y (a = 28.390(2), b = 10.068(1), c = 33.715(2) Å, β = 113.85(1)°), Gd (a = 28.327(2), b = 10.074(1), c = 33.822(2) Å, β = 114.297(7)°), Dy (a = 28.124(6), b = 10.003(2), c = 33.486(7) Å, β = 113.89(3)°), Yb (a = 28.178(3), b = 9.977(1), c = 33.392(4) Å, β = 113.65(1)°), and Lu (a = 28.169(6), b = 10.002(2), c = 33.432(7) Å, β = 113.54(3)°) are isotypic and crystallize in a new structure type (C2/c; Z = 12). Main feature are PS4 tetrahedra isolated from each other surrounding the Ln and Li atoms via their S atoms. The coordination number of the five crystallographically independent Ln atoms is eight, but the polyhedra are quite different and they are interlinked to larger units extending in [010]. The environment of the Li atoms is irregular and formed by five to six S atoms. The crystal structure is compared with that of Li9Ln2(PS4)5 (Ln: Nd, Gd). For the synthesis of Ag3Y(PS4)2 (a = 16.874(3), b = 9.190(2), c = 9.312(2) Å, β = 123.17(3)°) a mixture of Y, P, S, and Ag2S was heated to 700 °C (50 h). The thiophosphate crystallizes in a new structure type (C2/c; Z = 4) composed of isolated PS4 tetrahedra. The two crystallographically independent Ag atoms are surrounded by four S atoms in the shape of distorted tetrahedra. The Ag(1)S4 polyhedra are cornershared to strands running along [001], which are linked together via Ag(2)S4 tetrahedra. The environment of the Y atoms is composed of eight S atoms each building distorted square antiprisms. These polyhedra are connected with each other via common edges to a strand running along [001].  相似文献   

8.
The title compounds, bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ2N1:P}disilver bis(perchlorate) acetonitrile monosolvate, [Ag2(C18H17N2P)2](ClO4)2·CH3CN, (1), and bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ2N1:P}bis[(nitrato‐κ2O,O)silver], [Ag2(C18H17N2P)2(NO3)2], (2), each contain disilver macrocyclic [Ag2(C18H17N2P)2]2+ cations lying about inversion centres. The cations are constructed by two N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine (DPP) ligands linking two Ag+ cations in a head‐to‐tail fashion. In (1), the unique Ag+ cation has a near‐linear coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands. Two ClO4 anions doubly bridge two metallomacrocycles through Ag...O and N—H...O weak interactions to form a chain extending in the c direction. The half‐occupancy acetonitrile molecule lies with its methyl C atom on a twofold axis and makes a weak N...Ag contact. In (2), there are two independent [Ag(C18H17N2P)]+ cations. The nitrate anions weakly chelate to each Ag+ cation, leading to each Ag+ cation having a distorted tetrahedral coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands, and two chelating nitrate O atoms. Each dinuclear [Ag2(C18H17N2P)2(NO3)2] molecule acts as a four‐node to bridge four adjacent equivalent molecules through N—H...O interactions, forming a two‐dimensional sheet parallel to the bc plane. Each sheet contains dinuclear molecules involving just Ag1 or Ag2 and these two types of sheet are stacked in an alternating fashion. The sheets containing Ag1 all lie near x = , , etc, while those containing Ag2 all lie near x = 0, 1, 2 etc. Thus, the two independent sheets are arranged in an alternating sequence at x = 0, , 1, etc. These two different supramolecular structures result from the different geometric conformations of the templating anions which direct the self‐assembly of the cations and anions.  相似文献   

9.
Building on previous single crystal X‐ray structure determinations for the group 1 salts of complex thiosulfate/univalent coinage metal anions previously defined for (NH4)9AgCl2(S2O3)4, NaAgS2O3·H2O and Na4[Cu(NH3)4][Cu(S2O3)2]·NH3, a wide variety of similar salts, of the form , M1 = group 1 metal cation, M2 = univalent coinage metal cation (Cu, Ag), (X = univalent anion), most previously known, but some not, have been isolated and subjected to similar determinations. These have defined further members of the isotypic, tetragonal series, for M1 = NH4, M2 = Cu, Ag, X = NO3, Cl, Br, I, together with the K/Cu/NO3 complex, all containing the complex anion [M2(SSO3)4]7? with M2 in an environment of symmetry, Cu, Ag‐S typically ca. 2.37, 2.58Å, with quasi‐tetrahedral S‐M‐S angular environments. Further salts of the form , n = 1‐3, have also been defined: For n = 3, M2 = Cu, M1/x = K/2.25 or 1 5/6, NH4/6, (and also for the (NH4)4Na/4H2O·MeOH adduct) the arrays take the form with distorted trigonal planar CuS3 coordination environments, Cu‐S distances being typically 2.21Å, S‐Cu‐S ranging between 105.31(4)–129.77(4)°; the silver counterparts take the form for M1 = K, NH4. For n = 2, adducts have only been defined for M2 = Ag, the anions of the M1 = Na, K adducts being dimeric and polymeric respectively: Na6[(O3SS)2Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, K3[Ag(μ‐SSO3)2](∞|∞)·H2O; a polymeric copper(I) counterpart of the latter is found in Na5Cu(NO3)2(S2O3)2 ≡ 2NaNO3·Na3[Cu(μ‐SSO3)2](∞|∞). For n = 1, NaAgS2O3, the an‐ and mono‐ hydrates, exhibit a two‐dimensional polymeric complex anion in both forms but with different contributing motifs. (NH4)13Ag3(S2O3)8·2H2O takes the form (NH4)13[{(O3SS)3Ag(μ‐SSO3)}2Ag], a linearly coordinated central silver atom linking a pair of peripheral [Ag(SSO3)4]7? entities. In Na6[(O3SS)Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, the binuclear anions present as Ag2S4 sheets, the associated oxygen atoms being disposed to one side, thus sandwiching layers of sodium ions; the remarkable complex Na5[Ag3(S2O3)4](∞|∞)·H2O is a variant, in which one sodium atom is transformed into silver, linking the binuclear species into a one‐dimensional polymer. In (NH4)8[Cu2(S2O3)5]·2H2O a binuclear anion of the form [(O3SS)2Cu(μ‐S.SO3)Cu(SSO3)2]8? is found; the complex (NH4)11Cu(S2O3)6 is 2(NH4)2(S2O3)·(NH4)7[Cu(SSO3)4]. A novel new hydrate of sodium thiosulfate is described, 4Na4S2O3·5H2O, largely describable as sheets of the salt, shrouded in water molecules to either side, together with a redetermination of the structure of 3K2S2O3·H2O.  相似文献   

10.
Ag4Bi2O5 — A Novel Silverbismuthate(III) Yellow single crystals of Ag4Bi2O5 have been obtained for the first time by solid state reaction of Ag2O and Bi2O3 applying an oxygen pressure of 10 MPa at a temperature of 473 K. According to the results of a single crystal structure determination (Pnna, a = 1428.3(2), b = 569.2(1), c = 877.7(1) pm, Z = 4, 1544 diffractometer data, R1 = 0.050, wR2 = 0.094) the anionic partial structure of Ag4Bi2O5 consists of chains of corner and edge sharing BiO4-units. The silveratoms form a network of threedimensionally connected trigonal bipyramides with Ag? Ag-contacts between 285 and 323 pm.  相似文献   

11.
Ag9I3(SeO4)2(IO3)2 was obtained for the first time by reacting a stoichiometric mixture of Ag2O, AgI and SeO2 at elevated oxygen pressure (255 MPa) and at a temperature of 500 °C. Ag9I3(SeO4)2(IO3)2 was characterized by X‐ray powder diffraction, differential scanning calorimetry, impedance spectroscopy and single crystal structure analysis. The crystal structure was solved by direct methods (I23, Z = 8, a = 12.9584(6) Å, V = 2175.9(2) Å3 and R1 = 2.70 %). The crystal structure consists of isolated SeO4 tetrahedra and trigonal IO3 pyramids separated by Ag+ and I ions. Each four of the SeO42– and IO3 anions aggregate, forming a novel supramolecular building block, showing a hetero‐cubane like structure. According to the results of impedance measurements, Ag9I3(SeO4)2(IO3)2 is a good silver ion conductor. The compound shows an abrupt increase in the ionic conductivity in the temperature range of 115 to 147 °C, and has a silver ion conductivity of 7.1 × 10–5 Ω–1 cm–1 at 25 °C. The activation energy for silver ion conduction is 0.45 eV, in the temperature range from 25 to 115°.  相似文献   

12.
The 2‐D heteronuclear coordination polymer {[Ag4Fe2(SCN)12(H2O)2] (inaH)2(H2O)2}n (1) (inaH is the abbreviation of protonated isonicotinic acid) with chemical formula C24Ag4Fe2N14O8S12 has been synthesized and characterized by single crystal X‐ray diffraction, elemental analysis and IR spectroscopy. The Ag2S2 rings connect two kinds of octahedral geometries of Fe(III) ions, [Fe(NCS)6]3– and Fe(H2O)2(NCS)4]? units with bridging thiocyanate ions leading to 2‐D [Ag4Fe2(SCN)12(H2O)22– anion framework. Four kinds of rings including the unprecedented thirty‐two membered Ag4Fe4(SCN)8 rings share comers or edges in the 2‐D anion layer structure. All thiocyanates coordinate to the metal ions according to the HSAB principle with N atoms binding to the Fe(III) ions and with S atoms binding to Ag(I) ions. Pronoated ina cations stabilize the layer structure as counter ions and hydrogen bonds were formed within the pronoated in a cations dimer and between the dimers and the lattice waters. Crystal data: Mr= 1560.44, triclinic, P1, a=0.76082(1) nm, b=0.9234 nm, c= 1.85611(4) nm, a= 103.0170(10)°, β=93.7780(10)°, y=97.4080(10)°, V= 1.25385(3) nm3, Z=1, μ(Mo Kα)=2.650 mm?1, Dc,=2.067 g · cm?3, F(000)=758, R1=0.0412. wR2=0.1003.  相似文献   

13.
Preparation, Raman Spectra, and Crystal Structures of V2O3(SO4)2, K[VO(SO4)2], and NH4[VO(SO4)2] The oxo-sulfato-vanadates(V) V2O3(SO4)2, K[VO(SO4)2], and NH4[VO(SO4)2] have been prepared as crystals suitable for X-ray structure determination. In all structures sulfate acts as an unidentate ligand only toward a single vanadium atom. The structure of V2O3(SO4)2 consists of a threedimensional network of pairs of cornershared VO6 octahedra with one terminal oxygen atom each, and SO4 tetrahedra. All oxygen atoms of the sulfate ions are coordinated. NH4[VO(SO4)2] and K[VO(SO4)2] are isostructural. VO6 octahedra with one terminal oxygen atom and pairs of sulfate tetrahedra form infinite chains by corner sharing. The chains are weakly interlinked to layers. The sulfate ions are distorted towards planar SO3 molecules and single oxygen atoms attached to vanadium. This structural detail gives an explanation for the mechanism of the reversible reaction K[VO(SO4)2] ? K[VO2(SO4)] + SO3 at 400°C. Raman spectra of the compounds have been recorded and interpreted with respect to their structures. Crystal data: V2O3(SO4)2, monoclinic, space group P21/a, a = 947.2(4), b = 891.3(3), c? 989.1(4) pm, β = 104.56(3)°, Z = 4, 878 unique data, R(Rw) = 0.039(0,033); K[VO(SO4)2], orthorhombic, space group P212121, a = 495.3(2), b = 869.6(9), c = 1 627(1)pm, Z = 4, 642 unique data, R(Rw) = 0,11(0,10); NH4[VO(SO4)2], orthorhombic, space group P212121, a = 495.3(1), b = 870.0(2), c = 1 676.7(4)pm, Z = 4, 768 unique data, R(Rw) = 0.088(0.083).  相似文献   

14.
Two Ag(I) complexes, [Ag2(bobb)2]⋅(NO3)2 ( 1 ) and [Ag2(crotonate)2(aobb)]n ( 2 ) (bobb =1,3‐bis(1‐benzylbenzimidazol‐2‐yl)‐2‐oxapropane; aobb =1,3‐bis(1‐allylbenzimidazol‐2‐yl)‐2‐oxopropane), have been synthesized and characterized using elemental analysis, electrical conductivities, infrared and UV–visible spectral measurements and single‐crystal X‐ray diffraction. Complex 1 is binuclear and three‐coordinated by two N atoms from two bobb ligands, while complex 2 is a unique metal organic compound with diamond‐like multinuclear Ag centers with each Ag bridged by two aobb ligands and two crotonate ions to form one‐dimensional single polymer chain structures and extended into two‐dimensional frameworks through π–π and intermolecular C─H⋅⋅⋅O hydrogen bonds. The adjacent Ag(I) centers are bridged by allyl from aobb which is not only a σ‐bonding ligand, but also a π‐acid ligand. The DNA binding modes of complexes 1 and 2 were investigated using electronic absorption titration, fluorescence spectra and viscosity measurements. The results suggest that the two complexes bind to DNA via an intercalative mode, and their binding affinity for DNA follows the order 2  >  1 . This is due to the chelating effects which can enhance the planar functionality of the metal complexes.  相似文献   

15.
New Phosphido-bridged Multinuclear Complexes of Ag, Cd and Zn. The Crystal Structures of [Ag4(PPh2)4(PMe3)4], [Ag6(PPh2)6(PtBu3)2] and [M4Cl4(PPh2)4(PnPr3)2] (M = Zn, Cd) AgCl reacts with Ph2PSiMe3 in the presence of a tertiary Phosphine PMe3 or PtBu3 to form the multinuclear complexes [Ag4(PPh2)4(PMe3)4] ( 1 ) and [Ag6(PPh2)6(PtBu3)2] ( 2 ). In analogy to that MCl2 reacts with Ph2PSiMe3 in the presence of PnPr3 to form the two multinuclear complexes [M4Cl4(PPh2)4(PnPr3)2] (M = Zn ( 3 ), Cd ( 4 )). The structures were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (Nr. 33), Z = 4, a = 1 313.8(11) pm, b = 1 511.1(6) pm, c = 4 126.0(18) pm, 2 : space group P1 (Nr. 2), Z = 2, a = 1 559.0(4) pm, b = 1 885.9(7) pm, c = 2 112.4(8) pm, α = 104.93(3)°, β = 94.48(3)°, γ = 104.41(3)°; 3 : space group C2/c (Nr. 15), Z = 4, a = 2 228.6(6) pm, b = 1 847.6(6) pm, c = 1 827.3(6) pm, β = 110.86(2); 4 : space group C2/c (Nr. 15), Z = 4, a = 1 894.2(9) pm, b = 1 867.9(7) pm, c = 2 264.8(6) pm, β = 111.77(3)°). 3 and 4 may be considered as intermediates on the route towards polymeric [M(PPh2)2]n (M = Zn, Cd).  相似文献   

16.
During the exploration of the K2O-Bi2O 3 -As2O5 system, single crystals of a new arsenate of trivalent bismuth, K3Bi5(AsO4) 6, were isolated by solid state reaction at 600°C. The title compound crystallizes in the monoclinic system, space group C2/c (N°15) with a = 18.257(2) Å, b = 7.260(1) Å, c = 20.130(4) Å, β = 119.86(1)°, and Z = 4. Its structure consists of a three-dimensional framework made up of AsO4 tetrahedra and BiO6 and BiO7 polyhedra sharing edges and corners, delimiting cavities wherein K+ ions reside. This compound exhibits a potassium ion conductivity but with rather low conductivity value.  相似文献   

17.
K3FeSe3 and K3Fe2Se4, Two New Compounds in the System K/Fe/Se The two selenides K3FeSe3 and K3Fe2Se4 were synthesised by fusion reactions of potassium carbonate with iron and selenium in a stream of hydrogen charged with selenium at 695 °C and 710–730 °C, respectively. The crystal structures were determined by single‐crystal X‐ray diffractometer data. The atomic arrangement of K3FeSe3 is characterised by edge sharing [Fe2Se6] double tetrahedra separated by potassium ions (space group P21/c, Z = 4). The characteristic structural unit of the mixed‐valent compound K3Fe2Se4 is a zig‐zag chain of edge‐sharing, iron‐centred selenium tetrahedra, again separated by potassium ions (space group Pnma, Z = 4).  相似文献   

18.
The first silver bismuth borate, AgBi2B5O11 (silver dibismuth pentaborate), has been prepared via glass crystallization in the Ag2O–Bi2O3–B2O3 system and characterized by single‐crystal X‐ray diffraction. Its structure is derived from that of centrosymmetric Bi3B5O12 by ordered substitution of one Bi3+ ion for Ag+, which results in the disappearance of the mirror plane and inversion centre. Second harmonic generation (SHG) measurements confirm the acentric crystal structure. It is formed by [Bi2B5O11] layers stretched along c and comprised of vertex‐sharing B5O10 and BiO3 groups which incorporate the Ag+ cations. The new compound was characterized by thermal analysis, high‐temperature powder X‐ray diffraction, and vibrational and UV–Vis–NIR (near infrared) spectroscopy. Its thermal expansion is strongly anisotropic due to the presence of rigid B5O10 groups aligned in a parallel manner. The minimal value is observed along their axis [parallel to c, αc = 3.1 (1) × 10?6 K?1], while maximal values are observed in the ab plane [αa = 20.4 (2) and αb = 7.8 (2) × 10?6 K?1]. Upon heating, AgBi2B5O11 starts to decay above 684 K due to partial reduction of silver; incongruent melting is observed at 861 K. According to density functional theory (DFT) band‐structure calculations, the new compound is a semiconductor with an indirect energy gap of 3.57 eV, which agrees with the experimental data (absorption onset at 380 nm).  相似文献   

19.
Hydrothermally synthesized dipotassium gallium {hydrogen bis[hydrogenphosphate(V)]} difluoride, K2Ga[H(HPO4)2]F2, is isotypic with K2Fe[H(HPO4)2]F2. The main features of the structure are ([Ga{H(HPO4)2}F2]2−)n columns consisting of centrosymmetric Ga(F2O4) octahedra [average Ga—O = 1.966 (3) Å and Ga—F = 1.9076 (6) Å] stacked above two HPO4 tetrahedra [average P—O = 1.54 (2) Å] sharing two O‐atom vertices. The charge‐balancing seven‐coordinate K+ cations [average K—O,F = 2.76 (2) Å] lie in the intercolumn space, stabilizing a three‐dimensional structure. Strong [O...O = 2.4184 (11) Å] and medium [O...F = 2.6151 (10) Å] hydrogen bonds further reinforce the connections between adjacent columns.  相似文献   

20.
A new metal borophosphate PbII4{Co2[B(OH)2P2O8](PO4)2}Cl ( 1 ), containing both Pb2+ cations and Cl anions, was hydrothermally synthesized and characterized by powder X‐ray diffraction, ICP, TG/DTA, and FTIR spectroscopic analyses. The crystal structure determination from single‐crystal X‐ray diffraction reveals that compound 1 crystallizes in the trigonal space group R c (No. 167), a = 9.7513(7) Å, c = 91.060(13) Å, V = 7498.7(13) Å3 and Z = 18. Its structure features a new cobalt borophosphate layer {Co2[B(OH)2P2O8](PO4)2}7– built up from CoO5 square pyramids, [B(OH)2P2O8]5– borophosphate trimers and PO4 tetrahedra. Extra‐framework Pb2+ and Cl ions are located at the vacancy of layers to achieve the charge neutrality of the framework. Magnetic measurements indicate that antiferromagnetic interactions exist between Co2+ ions with a negative Weiss constant of –20.3 K.  相似文献   

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