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1.
Framework Compounds with Mobile LaIII Cations: Syntheses, Crystal Structures and Structural Dynamics of the Lanthanum(III) Iron(II) Sulfide Halides La53Fe12S90X3 (X = Cl, Br, I) Black crystals of La53Fe12S90X3 (X = Cl, Br, I) were synthesized from La2S3 and FeS in a reactive LaX3 flux at 1320 K. The structures were determined by single‐crystal X‐ray diffraction. The compounds are isostructural, crystallizing in the rhombohedral space group with Z = 1 (La53Fe12S90Cl3: a = 14.0154(7), c = 21.888(1) Å, V = 3723.5(3) Å3; La53Fe12S90Br3: a = 14.0048(9), c = 22.040(2) Å, V = 3743.6(4) Å3; La53Fe12S90I3: a = 13.9805(8), c = 22.108(2) Å, V = 3742.2(4) Å3). The structure adopted is a stuffed variant of the La52Fe12S90 structure type. [FeII2S9] dimers of face‐sharing octahedra are linked by face‐ and vertex‐sharing bi‐ or tri‐capped [LaIIIS6+n] trigonal prisms, forming a three‐dimensional framework containing cuboctahedral cavities of two sizes. The larger cavities, which remain empty in the structure of La52Fe12S90, are filled by halide ions in La53Fe12S90X3. The smaller cavities accommodate numerous sites for disordered lanthanum cations, modelling a network of diffusion pathways through the structure. An analogous picture is obtained from the calculation of the periodic nodal surface (PNS): The PNS separates a labyrinth containing the framework atoms from a labyrinth containing the mobile lanthanum cations. Molecular dynamic simulations confirm a strong coupling between the motions of the mobile lanthanum ions and the neighbouring sulfide ions.  相似文献   

2.
Thiosilicates of the Rare‐Earth Elements: III. KLa[SiS4] and RbLa[SiS4] – A Structural Comparison Pale yellow, platelet shaped, air‐ and water resistant single crystals of KLa[SiS4] derived from the reaction of lanthanum (La) and sulfur (S) with silicon disulfide (SiS2) in a molar ratio of 2 : 3 : 1 with an excess of potassium chloride (KCl) as flux and source of potassium ions in evacuated silica ampoules at 850 °C within seven days. The analogous reaction utilizing a melt of rubidium chloride (RbCl) instead also leads to yellow comparable single crystals of RbLa[SiS4]. The potassium lanthanum thiosilicate crystallizes monoclinically with the space group P21/m (a = 653.34(6), b = 657.23(6), c = 867.02(8) pm, β = 107.496(9)°) and two formula units per unit cell, while the rubidium lanthanum thiosilicate has to be assigned orthorhombically with the space group Pnma (a = 1728.4(2), b = 667.23(6), c = 652.89(6) pm) and four formula units in its unit cell. In both compounds the La3+ cations are surrounded by 8+1 sulfide anions in the shape of tricapped trigonal prisms. The Rb+ cations in RbLa[SiS4] show a coordination number of 9+2 relative to the S2? anions, which form pentacapped trigonal prisms about Rb+. This coordination number, however, is apparently too high for the K+ cations in KLa[SiS4], so that they only exhibit a bicapped trigonal prismatic environment built up by eight S2? anions. The isolated thiosilicate tetrahedra [SiS4]4? of the rubidium compound are surrounded by La3+ both edge‐ and face‐capping, but terminal as well as edge‐ and face‐spanning by Rb+. In the potassium compound there is no change for the La3+ environment about the [SiS4]4? tetrahedra, but the K+ cations are only able to attach terminal and via edges. The whole structure is built up by anionic equation/tex2gif-stack-1.gif{La[SiS4]}? layers that are separated by the alkali metal cations. In direct comparison the two thiosilicate structures can be regarded as stacking variants.  相似文献   

3.
Tricerium(III) diiron(II,III) hepta­sulfide, Ce3Fe1.94S7, crystallizes in the polar hexagonal space group P63 and adopts the Ce6Al3.33S14 structure type. The Fe atoms occupy both tetrahedral and octahedral sites. Isolated FeS4 tetrahedra, all pointing in the same direction, are stacked along the threefold rotation axes. Chains of face‐sharing FeS6 octahedra propagate along the 63 axis. Vacancies resulting from the partial oxidation of Fe2+ to Fe3+ occur exclusively in the octahedral Fe sites. The Ce atoms are coordinated by [7+1] S atoms, which form bicapped trigonal prisms.  相似文献   

4.
The structure of rhombohedral (R) iron(III) tris­[di­hydrogen­phosphate(I)] or iron(III) hypophosphite, Fe(H2PO2)3, has been determined by single‐crystal X‐ray diffraction. The structure consists of [001] chains of Fe3+ cations in octa­hedral sites with symmetry bridged by bidentate hypophosphite anions.  相似文献   

5.
Two one‐dimensional zinc‐based coordination polymers containing cyanate anions are reported. catena‐Poly[sodium [[tricyanato­zinc(II)]‐μ‐1,4‐diaza­bicyclo­[2.2.2]octane‐κ2N:N′]], {Na[Zn(NCO)3(C6H12N2)]}n, consists of linear [tricyanato­zinc(II)]‐μ‐1,4‐diaza­bicyclo­[2.2.2]octane strands in which the Zn2+ cations adopt trigonal–bipyramidal coordination on sites of m2 point symmetry. Na+ cations lie between the strands on sites of m point symmetry, coordinated in a distorted octa­hedral geometry by six O atoms of the cyanate anions. catena‐Poly[[dicyanato­zinc(II)]‐μ‐4,4′‐bipyridine‐κ2N:N′], [Zn(NCO)2(C10H8N2)]n, crystallizes in the space group P21/n with Z′ = 5. The structure consists of zigzag strands formed by Zn2+ cations linked via 4,4′‐bipyridine. Each Zn2+ cation adopts a tetra­hedral coordination, with two sites occupied by 4,4′‐bipyridine and two cyanate anions completing the coordination sphere. The structure is closely comparable with the thio­cyanate and halide analogues [ZnX2(C10H8N2)] (X = NCS, Cl or Br).  相似文献   

6.
In the title compound, catena‐poly[[tri­silver(I)‐tri‐μ3N,N‐diethyl­dithio­carbamato‐3′κS:1κS′:2κS;1κS:2κS′:3κS;2κS:3κ2S,S′:1′κS′], [Ag3(C5H10NS2)3]n, the trigonally and tetra­hedrally coordinated Ag atoms are μ3‐bridged by κ3‐ and κ4‐S2CNEt2 ligands to form a ribbon structure along the c axis. There is a twofold axis parallel to the b axis and passing through the tetra­hedrally coordinated Ag atom. The S2CNEt2 ligands coordinate the Ag atoms in η12‐ and η22‐fashions, depending on the bridging S atoms. The distances between the trigonal Ag and S atoms are 2.4915 (11)–2.6205 (11) Å, while those between the tetra­hedral Ag and S atoms are 2.5457 (11) and 2.7145 (10) Å. The shortest Ag⋯Ag distance between trigonal Ag atoms is 2.8336 (7) Å, which indicates a weak Ag⋯Ag inter­action, whereas the shortest distance between trigonal and tetra­hedral Ag atoms is 3.463 (6) Å, which is considered as non‐bonding.  相似文献   

7.
Crystals of pentalanthanum pentatitanium heptadecaoxide (La5Ti5O17 with 0.3% oxy­gen excess, or LaTiO3.41) have been synthesized by floating‐zone melting, and the structure has been solved using single‐crystal X‐ray diffraction intensities. The monoclinic (P21/c) structure consists of perovskite‐like slabs of vertex‐sharing TiO6 octahedra, which are separated by additional oxy­gen layers. The slabs are five octahedra wide. Due to the adjustment of the TiO6 octahedra to meet the coordination requirements of the La3+ cations, a superstructure develops along the a axis.  相似文献   

8.
Potassium scandium niobate hydroxide, K3(Sc0.875Nb0.125)Nb2O9H1.75, is a new scandium niobate with a unique cage structure. The structure contains two non‐equivalent K+ sites (3m and m2 site symmetry), one disordered Sc3+/Nb5+ site (m site symmetry), one Nb5+ site (3m site symmetry), two O2− sites (m and mm2 site symmetry) and one H+ site (m site symmetry). Both scandium and niobium have octahedral environments, which combine to form cages around potassium. One K atom lies in a cube‐like cage built of seven octahedra, while the other K atom is encapsulated by an eight‐membered trigonal face‐bicapped prism. The cages form sheets that extend along the ab plane.  相似文献   

9.
The title compound, poly[diammine­hexa‐μ‐cyano‐di­copper(I)­copper(II)­mercury(II)], [Cu3Hg(CN)6(NH3)2]n, has a novel threefold‐inter­penetrating structure of three‐dimensional frameworks. This three‐dimensional framework consists of two‐dimensional network Cu3(CN)4(NH3)2 complexes and rod‐like Hg(CN)2 complexes. The two‐dimensional network complex contains trigonal–planar CuI (site symmetry m) and octa­hedral CuII (site symmetry 2/m) in a 2:1 ratio. Two types of cyanide group form bridges between three coordination sites of CuI and two equatorial sites of CuII to form a two‐dimensional structure with large hexa­gonal windows. One type of CN group is disordered across a center of inversion, while the other resides on the mirror plane. Two NH3 mol­ecules (site symmetry 2) are located in the hexa­gonal windows and coordinate to the remaining equatorial sites of CuII. Both N atoms of the rod‐like Hg(CN)2 group (Hg site symmetry 2/m and CN site symmetry m) coordinate to the axial sites of CuII. This linkage completes the three‐dimensional framework and penetrates two hexa­gonal windows of two two‐dimensional network complexes to form the threefold‐inter­penetrating structure.  相似文献   

10.
The structure of bis­[4,5‐ethyl­enedi­thio‐2‐(4,5‐ethyl­enedi­thio‐1,3‐diselena­cyclo­pent‐4‐en‐2‐yl­idene)‐1,3‐diselena­cyclo­pent‐4‐enium] bis(μ‐1,2,5‐thia­diazo­le‐3,4‐di­thiol­ato‐κ3S4,S5:S4)bis[(1,2,5‐thia­diazo­le‐3,4‐di­thiol­ato‐κ2S4,S5)­iron(III)], (BETS)2[Fe(tdas)2]2 [BETS is alternatively called bis­(ethyl­enedi­thio)­tetraselenafulvalenium] or (C10H8S4Se4)2[{Fe(C2N2S3)2}2], consists of segregated columns of dimers of BETS and columns of dimers of [Fe(tdas)2]. Each dimer displays inversion symmetry. Numerous chalcogen–chalcogen contacts are observed within and between the columns, producing a network of interactions responsible for the metal‐like behaviour of the compound.  相似文献   

11.
Transparent yellow plates of rubidium manganese hexa­thio­diphosphate, Rb2MnP2S6, were synthesized in molten RbBr. The compound is isotypic to other compounds of the type A2MP2Q6 (A = K, Rb, Cs; M = Mn, Fe; Q = S, Se). Its structure can be viewed as columns of face‐sharing S6 polyhedra parallel to the a axis, interconnected by Rb+. The S6 polyhedra are centered alternately by Mn (in octahedral coordination) and P2 units (in trigonal antiprisms). The Mn atom and P2S6 group lie on centers of symmetry.  相似文献   

12.
The title compound, hexadecalanthanum pentatitanium heptadeca­sulfide heptadecaoxide, La16Ti5S17+xO17 [x = 0.75 (9)], has been obtained as a by‐product in the preparation of new oxy­chalcogenide compounds in the La/Ti/Ag/S/O system. La16Ti5S17+xO17 crystallizes in the tetragonal system (space group I4/m) and is isostructural with Nd16Ti5S17O17. The structure of the title compound consists of an [La2S2] rock‐salt‐type framework, which delimits [001] square channels containing two types of chains of corner‐sharing Ti(O,S)6 octahedra. These chains are connected through La(O,S)n polyhedra.  相似文献   

13.
The title compound, {(C9H14N)4[Pb3I10]}n, crystallizes as an organic–inorganic hybrid. As such, the structure consists of a two‐dimensional inorganic layer of [Pb3I10]n4n ions extending along [100]. The asymmetric unit contains two independent Pb atoms, viz. one in a general position and the other on an inversion centre. Each Pb atom is octa­hedrally coordinated by six iodide ions and exhibits both face‐ and corner‐sharing with adjacent atoms in the inorganic layer. These anionic layers alternate with 3‐phenyl­propyl­ammonium cations, which hydrogen bond to the iodides. Simple face‐to‐edge σ–π stacking inter­actions are observed between the aromatic rings that stabilize the overall three‐dimensional structure. This net structure has only been observed five times previously.  相似文献   

14.
The silver bismuth trideca­sulfide Ag3.5Bi7.5S13 crystallizes in the monoclinic space group C2/m. Its structure is built up of two alternating kinds of layered modules parallel to (001). In the module denoted A, octa­hedra around the metal positions (M = Ag/Bi, M2 and an S atom on 2/m, other atoms on m) alternate with paired monocapped trigonal prisms around Bi. The NaCl‐type module B is composed of parallel eight‐membered chains of edge‐sharing octa­hedra running dia­gonally across it. Ag3.5Bi7.5S13 is the member with N = 8 of the pavonite homologous series NP of ternary compounds with the general formula [Bi2S3]2·[AgBiS2](N−1)/2.  相似文献   

15.
In sodium hexa­amminecobalt(III) tetra­kis­(4‐fluoro­benzoate) monohydrate, Na[Co(NH3)6](C7H4FO2)4·H2O, determined at 180 K, [Co(NH3)6]3+ cations lie on centres of inversion and form layers in which their C4 axes lie perpendicular to the layer planes. 4‐Fluoro­benzoate anions lie on twofold axes and general positions and adopt near‐planar geometries. Na+ cations and water mol­ecules lie on twofold axes, forming [NaO5] square pyramids that lie between the [Co(NH3)6]3+ cations. The second‐sphere inter­actions between [Co(NH3)6]3+ cations and 4‐fluorobenzoate anions comprise edge‐to‐face and vertex‐to‐face arrangements. The structure is closely comparable with that of the benzoic acid salt, demonstrating that fluorination of the anion in the para position has no significant influence on the second‐sphere inter­actions and minimal influence on the gross crystal structure.  相似文献   

16.
A polymeric heterometallic compound, {[Gd2Zn3(C4H4O5)6(H2O)6]·12H2O}n, comprising zinc(II) and gadolinium(III) cations bridged by carboxyl­ate groups from oxy­di­acetate ligands, is presented. The GdIII cations lie at sites with crystallographic 32 symmetry and display a tricapped trigonal‐prism arrangement, which is defined by six carboxyl and three ether O atoms. The ZnII cations lie at sites with imposed 2/m symmetry and are octahedrally coordinated by four carboxyl O atoms and two apical water ligands, which form strong intramolecular hydrogen bonds. Comparison is made with the previously reported isostructural homologous copper–gadolinium complex.  相似文献   

17.
The title compound, hexapotassium octairon(II,III) dodecaphosphonate, exhibiting a two‐dimensional structure, is a new mixed alkali/3d metal phosphite. It crystallizes in the space group Rm, with two crystallographically independent Fe atoms occupying sites of m (Fe1) and 3m (Fe2) symmetry. The Fe2 site is fully occupied, whereas the Fe1 site presents an occupancy factor of 0.757 (3). The three independent O atoms, one of which is disordered, are situated on a mirror and all other atoms are located on special positions with 3m symmetry. Layers of formula [Fe3(HPO3)4]2− are observed in the structure, formed by linear Fe3O12 trimer units, which contain face‐sharing FeO6 octahedra interconnected by (HPO3)2− phosphite oxoanions. The partial occupancy of the Fe1 site might be described by the formation of two [Fe(HPO3)2] layers derived from the [Fe3(HPO3)4]2− layer when the Fe1 atom is absent. Fe2+ is localized at the Fe1 and Fe2 sites of the [Fe3(HPO3)4]2− sheets, whereas Fe3+ is found at the Fe2 sites of the [Fe(HPO3)2] sheets, according to bond‐valence calculations. The K+ cations are located in the interlayer spaces, between the [Fe3(HPO3)4]2− layers, and between the [Fe3(HPO3)4]2− and [Fe(HPO3)2] layers.  相似文献   

18.
The title compound, (C3H10N)8[Pb5I18], crystallizes as an inorganic–organic hybrid. As such, the structure consists of two‐dimensional sheets of corner‐ and face‐sharing [PbI6]4− octa­hedra, separated by layers of 3‐propyl­ammonium cations, which hydrogen bond to the I atoms. The asymmetric unit contains six independent Pb atoms; four are on general positions and the other two are on special positions, viz. a centre of inversion and a twofold axis. The inorganic sheets show a never before seen motif.  相似文献   

19.
We present two ZnII‐ and CdII‐based coordination polymers (CPs), L ‐Zn and L ‐Cd , offering H‐bonding‐based cavities of varying dimensions. Both CPs were used for the highly selective detection of S2O72? and Fe3+ ions where H‐bonding based cavities played an important role. Fluorescence quenching, competitive binding studies and binding parameters substantiated significant recognition of S2O72? and Fe3+ ions by both CPs.  相似文献   

20.
The title compound is a new mixed alkali/3d metal phosphite. It exhibits a layered structure formed by linear Mn3O12 trimer units which contain face‐sharing MnO6 octahedra interconnected by (HPO3)2− phosphite oxoanions. The K+ cations located between the anionic [Mn3(HPO3)4]2− sheets are ninefold coordinated. The presence of the alkaline ion leads to the highest symmetry and shortest interlayer distance compared with two previous compounds showing the same anionic framework and having ammonium salts as cations. The compound crystallizes in the space group Rm, with two crystallographically independent Mn atoms occupying sites of m and 3m symmetry. All the other atoms, except for the phosphite O atoms, are located on special positions with 3m symmetry.  相似文献   

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