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1.
The Antimonide Triantimonidometallates(III) Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3] The novel compounds Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3] are formed from stoichiometric mixtures of Cs, AlSb (GaSb) and KSb in sealed niobium ampoules at 950 K. The hexagonal structures are especially characterized by one-dimensional rod packings 1∞[Cs6K3Sb] which are formed from columns of condensed (Cs6K6/2) icosahedra. The icosahedra are centered by Sb3-? anions. The trigonal planar anions [AlSb3]6-? and [GaSb3]6-? are embedded between the icosahedra columns, and they are coordinated by alkali metal atoms. The FIR spectra were assigned to the vibrations of the [MSb3]6-? anions, with respect to the 6 m2-D3h symmetry. (P63/mmc, No. 194; a = 1101.7 and 1097.2 pm; c = 1158.9 and 1150.1 pm; Z = 2; Single crystal data: 574 and 546 reflections; R = 0.073 and 0.029. Distances:d(Al? Sb) = 265.4 pm; d(Ga? Sb) = 265.1 pm; d(Sb? Cs) = 401.6–423.0 pm; d(Sb? K) = 358.6–367.3 pm).  相似文献   

2.
Cs4[IrO4], a New Iridate with Planar Anion [IrO4]4? For the first time we obtained black single crystals of Cs4[IrO4] by heating intimate mixtures of CsO0.52 and IrO2 (molar ratio Cs : Ir = 4.30 : 1.00; “Ag-bomb”, 740°C/86 d). Cs4[IrO4] crystallizes monocline, C 2/m, with a = 1031.66(8) pm, b = 671.61(4) pm, c = 660.44(6) pm, b? = 108.118(7)° and Z = 2 in the K4[IrO4]-type. The structure has been determined by four-circle-diffractometer data (PW 1100 from Phillips, Ag? Kα , graphite) with 841 I0(hkl) with I ≥ 3s?(F) (from 947 I0(hkl) out of 3529 measured reflexes). The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.  相似文献   

3.
Cs[Er10(C2)2]I18 and [Er10(C2)2]Br18: Two New Examples for Reduced Halides of the Lanthanides with Isolated [M10(C2)2] Clusters Cs[Er10(C2)2]I18 is obtained from the reaction of ErI3 with caesium and carbon in sealed tantalum containers at 700°C and [Er10(C2)2]Br18 through the metallothermic reduction of ErBr3 with rubidium in the presence of carbon at 750°C in sealed niobium containers. The crystal structures {Cs[Er10(C2)2]I18: triclinic, P1 ; a = 1 105.2(8) pm, b = 1 112.0(7) pm; c = 1 122.9(8) pm; α = 66.91(3)°, β = 87.14(3)°; γ = 60.80(3)°; Z = 1; R = 0.049, Rw = 0.043; [Er10(C2)2]Br18: monoclinic, P21/n, a = 971.8(6) pm, b = 1 623.4(9) pm, c = 1 163.8(6) pm, β = 104.00(6)°; Z = 2; R = 0.077, Rw = 0.057} contain isolated dimeric [Er10(C2)2] clusters. Due to the inclusion of C2 units, the octahedra are elongated in the direction of the pseudo C4 axis. The connecting edges of the two octahedra are exceptionally short (316.7 pm and 314.8 pm respectively). The dimeric units are connected via Xi?a and Xa?i (X = Br, I) bridges according to [Er10(C2)2XX]X. Cs+ is surrounded by a cuboctahedron of iodide ions in Cs[Er10(C2)2]I18.  相似文献   

4.
On ?Lithovanadates”?: Rb2[LiVO4] and Cs2[LiVO4] By heating of well ground mixtures of the binary oxides [A2O, Li2O, V2O5, A : Li: V = 2.2 : 1.1 : 1.0 (A = Rb, Cs); Ni-tube, 750° 25 d] we obtained Rb2[LiVO4] and Cs2[LiVO4] colourless, orthorhombic single crystals. We found a new type of ?Lithovanadate”?-structure: space group Cmc21; a = 587.9(1), b = 1170.1(1), c = 793.3(1) pm, Z = 4 (A = Rb) bzw. a = 610.5(1), b = 1222.6(3), c = 815.5(2) pm, Z = 4 (A = Cs). The structure was determined by four-circle diffractometer data [MoKα -radiation; 997 from 1157 I0(hkl), R = 7.75%, Rw = 5.54% (A = Rb); 686 from 686 I0(hkl), R = 6.97%, Rw = 4.20% (A = Cs)] parameters see text. The Madelung part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.  相似文献   

5.
The Crystal Structures of (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN and [ReCl4(18)(Crown-6)] Brown single crystals of (NH4)2[ReCl6] are formed by the reaction of NH4Cl with ReCl5 in a suspension of diethylether. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN crystallizes as brown crystal plates from a solution of ReCl5 in acetonitrile. Lustrous green single crystals of [ReCl4(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl5 in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH4)2[ReCl6]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH4)2[PtCl6] type, the Re? Cl distance is 235.5(1) pm. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl2(CH3CN)4]+ ions with trans chlorine atoms, [ReCl6]2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl4(18-crown-6)]: Space group P21/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.  相似文献   

6.
Cs2[Pr6(C2)]I12 — the First Quaternary Reduced Halide with Isolated [M6(C2)] Clusters . Cs2[Pr6(C2)]I12 is obtained as one of the major products from the reaction of PrI3, cesium and carbon in sealed tantalum containers at 850°C. The crystal structure triclinic, P 1 ; a=948.1(2), b=953.6(3), c=1 005.2(3) pm; α=71.01(2); β=84,68(3), γ=89.37(2)°; Z=1 contains discrete Pr6I12-type clusters elongated along the pseudo-four-fold axis to accommodate the C2 units (d(C—C)=139 pm). The clusters are connected through common i?aI and a?iI linkages at metal vertices and edges according to Cs2[Pr6(C2)iI6i?aI6/2]a?iI6/2. The cesium cations occupy interstices within the (distorted) iodide layers in a way that “Cs2I18” dimers are formed, in which Cs+ is surrounded by eleven I?. On the basis of the MO scheme of [Sc6(C2]I11, the bonding of the C2 unit is discussed and compared with other cluster compounds containing C2 units.  相似文献   

7.
The First Binuclear Oxoferrate(II): ?Cs2K4[O2FeOFeO2]”? For the first time ?Cs2K4[Fe2O5]”? was obtained by annealing intimate mixtures of Cs2O, K2O, and CsFeO2 (molar ratio Cs : K : CsFeO2 1.3 : 2.1 : 1) in a closed Fe-cylinder (74 d; 470°C) in the form of red single crystals. The structure determination (four-circle diffractometer, MoKα , 760 out of 857 Io(h kl); R = 5.8%, Rw = 4.6%) confirms the space group C2/m; a = 707.4, b = 1138.5, c = 699.7 pm, β = 91.76°, Z = 2. Essential part of the structure is the binuclear, planar [O(1)2Fe? O(2)? FeO(1)2]6? group which is for the first time observed with oxoferrates(II). Despite different space groups the crystal structure is related to that of Rb2Na4[Co2O5].  相似文献   

8.
A new complex compound, [K2(18-crown-6)2[K(18-crown-6)(EtOH)]2[Er(NCS)6](SCN) (I), was synthesized and its crystal structure was studied by X-ray diffraction. In this work, the synthes and X-ray difraction stady of the crystals of a new complex, hexakis (isothiocyanato) erbiu(III) thiocyanate bis(18-crown-6) dipotassium bis(18-crown-6) ethanolpotassium], [K2(18-crown-6)2][K(18-crown-6)(ETON)]2[Er(NCS)6(SCN)(I)] are described. In crystal I, the alternating [Er(NCS)6]3? anions and binuclear complex cation [K(18-crown-6)2]2+ from infinite chains via the F-S bonds, while two complex cations [K(18-crown-6)(ETON)]+ and the statistically disordered SCN? anion between them are linked by the hydragen bonds O-H…S and O-H…N. Complex I contains the host-guest complex cations [K2(18-crown-6)2)]2+ and [K(18-crown-6)(ETON)]+ [1]. The alternating octabedral [Er(NCS)6]3? anions and binuclear complex cations [K2(18-crown-6)2]2+of crystal I form infinite chains via the K-S bonds, while two complex cations [K(18-crown-6)(EtOH)]+ and the statistically disordered SCN? anion lying between them are linked by interionic hydrogen bonds O-H…S and O-H…N. Complex I contains the host-guest complex cations [K2(18-crown-6)2]2+ and [K(18-crown-6)(EtOH)]+ [1].  相似文献   

9.
New Polyiodides of Cesium containing Double and Triple Decker Cations, [Cs(benzo‐18‐crown‐6)2]Ix and [Cs2(benzo‐18‐crown‐6)3](Ix)2 (x = 3, 5) [Cs(b18c6)2]Ix (x = 3 (1) , 5 (3) ) and [Cs2(b18c6)3](Ix)2 (x = 3 (2) , 5 (4) ) (b18c6 = benzo‐18‐crown‐6) have been synthesized by the reaction of benzo‐18‐crown‐6 (C16H24O6), cesium iodide (CsI) and iodine (I2) in acetonitrile ( 1 ), ethanol/dichloromethane ( 2 , 4 ) and 2‐methoxyethanol ( 3 ). Their crystal structures were determined on the basis of single crystal X‐ray data {( 1 ): monoclinic, C2/c, Z = 4, a = 2048.8(5), b = 1329.5(5), c = 1588.7(5) pm, β = 110.23(1)°; ( 2 ): monoclinic, C2/c, Z = 4, a = 2296.0(1), b = 2092.7(1), c = 1373.6(1) pm, β = 100.21(1)°; ( 3 ): monoclinic, P21/n, Z = 4, a = 1586.3(1), b = 1745.5(1), c = 1608.6(1) pm, β = 92.37(1)°; ( 4 ): triclinic, , Z = 2, a = 1241.7(1), b = 1539.8(2), c = 1938.4(2) pm, α = 91.15(1), β = 100.53(1), γ = 95.26(1)°}. As expected, double decker cations centered by Cs atoms, [Cs(b18c6)2]+, are found in the structures of ( 1 ) and ( 3 ). In contrast, the triple decker cation found in ( 2 ) and ( 4 ) is less common. The triiodide anions of ( 1 ) and ( 2 ) can be regarded as normal and the chain‐type pentaiodide anions of ( 3 ) and ( 4 ) fall into the known systematic sequence of these anions. The differences in the connectivity of the crystallographically independent I5? anions in ( 4 ) are surprising with respect to the fact that, so far, independent pentaiodide anions do not show variations in their scheme of connectivity within one crystal structure.  相似文献   

10.
CS[Er6C]I12 and cs2Lu[Lu6C]CI18: Examples for Quaternary Reduced Halides of the Lanthanides with Isolated “Clusters” Cs[Er6C]I12 and Cs2Lu[Lu6C]Cl18 were obtained as byproducts through metallothermic reductions of ErI3 and LuCl, with cesium in the presence of carbon in sealed tantalum containers at temperatures ranging from 700 to 940 °C. Cs2Lu[Lu6C]Cl18 (isostructural with Cs2Zr[Zr6H]Cl18, R 3 , a = 981.7 pm, c = 2723.2 pm, Z = 3, R = 0.082, R, = 0.053) contains octahedral [Lu6C] clusters which are slightly compressed along the threefold axis and edge-bridged by twelve chloride anions to form [Lu6C]Cl12 units. Six additional Cl in exo positions of the cluster provide octahedral coordination for the seventh Lu3+. Cs+ occupies anticuboctahedral interstices within the Cl+ layers as a part of the (hexagonal) closest packed arrangement. Cs[Er6C]I12 (trigonal, R 3, a = 1112.0pm, c = 2063.8pm, Z = 3, R = 0.094, R, = 0.068) exhibits [Er6C]I12 units as well and shows the structural framework of Sc[Sc6N]Cl12. Instead of Sc3+ in octahedral holes, cesium occupies a regular iodide position within the ccp sheets forming [CsI3] layers. Both halides are compared with other compounds of the lanthanides containing isolated [M6X12] clusters. The extreme electron deficiency is discussed.  相似文献   

11.
Crystal Structures of the Polytellurides [Ca(DMF)6]Te4, [Sr(15-Crown-5)2]Te4 · H2O, {[BaCl(18-Crown-6)(DMF)2]2[BaCl(18-Crown-6)(DMF) (H2O)]2(Te4)2}, and [Ph3PNPPh3]2Te5 · 2 DMF The title compounds were formed by alkalimetal polytelluride solutions in dimethylformamide (DMF) in the presence of the corresponding counter ions as well as in the presence of 15-crown-5 or 18-crown-6. Single crystals were obtained upon using additional diethylether. [Ca(DMF)6]Te4: Space group C2/c, Z = 4, 1024 observed unique reflections, R = 0.055. Lattice dimensions at ?70°C: a = 1776.1; b = 813.0 c = 2545.9pm; β = 102.90°. The compound consists of centrosymmetric [Ca(DMF)6]2+ ions, in which the calcium ions are octahedrally coordinated by the six oxygen atoms of the DMF molecules, and chain-like Te [Sr)15-crown-5)2]Te4 · H2O: Space group C2/c, Z = 4, 3322 observed unique reflections, R = 0.058. Lattice dimensions at ?70°C: a = 1450.5; b = 1407.3; c = 1660.9 pm; β = 110.22°. The compounds forms centrosymmetric cations [Sr(15-crown-5) 2]2+, in which the Sr2+ ion is sandwich-like surrounded by the ten oxygen atoms of the crown ether molecules, and chain-like Te42? ions, which are associated in the lattice forming polymeric chains. {[BaCl(18-crown-6)(DMF) 2]2[BaCl(18-crown-6)(DMF)· (H2O)] 2(Te4)2}: Space group P1 , Z = 1, 3189 observed unique reflections, R = 0.054. Lattice dimensions at 19°C: a = 986.1; b = 1052.8; c = 2696.4 pm; α = 89.34°; β = 88.68°; γ = 89.56°. The compound consists of chain-like Te ions without symmetry and of the two somewhat different cations [BaCl(18-crown-6)(DMF) 2]22+, in which the Ba2+ ions dimerize via centroysmmetric rings. Along with the six oxygen atoms of the crown ether molecules and the oxygen atoms of the DMF molecules, the oxygen atoms of the DMF and water molecule, respectively, the Ba+ ions achieve coordination number ten. [Ph3PNPPh3]2Te5 · 2DMF: Space group Pc, Z = 2, 5971 observed unique reflections, R = 0.058. Lattice dimensions at 20°C: a = 20°C: a = 1085.2; b = 1287.0; c = 2715.9 pm; β = 90.19°. The compounds consists of [Ph3PNPPh3]+ ions, chain-like Te52? ions, and incorporate DME molecules without bonding interaction. The 52? ions are associate via polymeric chains in which left- and right handed individuals are alternating.  相似文献   

12.
Three Alkali‐Metal Erbium Thiophosphates: From the Layered Structure of KEr[P2S7] to the Three‐Dimensional Cross‐Linkage in NaEr[P2S6] and Cs3Er5[PS4]6 The three alkali‐metal erbium thiophosphates NaEr[P2S6], KEr[P2S7], and Cs3Er5[PS4] show a small selection of the broad variety of thiophosphate units: from ortho‐thiophosphate [PS4]3? and pyro‐thiophosphate [S3P–S–PS3]4? with phosphorus in the oxidation state +V to the [S3P–PS3]3? anion with a phosphorus‐phosphorus bond (d(P–P) = 221 pm) and tetravalent phosphorus. In spite of all differences, a whole string of structural communities can be shown, in particular for coordination and three‐dimensional linkage as well as for the phosphorus‐sulfur distances (d(P–S) = 200 – 213 pm). So all three compounds exhibit eightfold coordinated Er3+ cations and comparably high‐coordinated alkali‐metal cations (CN(Na+) = 8, CN(K+) = 9+1, and CN(Cs+) ≈ 10). NaEr[P2S6] crystallizes triclinically ( ; a = 685.72(5), b = 707.86(5), c = 910.98(7) pm, α = 87.423(4), β = 87.635(4), γ = 88.157(4)°; Z = 2) in the shape of rods, as well as monoclinic KEr[P2S7] (P21/c; a = 950.48(7), b = 1223.06(9), c = 894.21(6) pm, β = 90.132(4)°; Z = 4). The crystal structure of Cs3Er5[PS4] can also be described monoclinically (C2/c; a = 1597.74(11), b = 1295.03(9), c = 2065.26(15) pm, β = 103.278(4)°; Z = 4), but it emerges as irregular bricks. All crystals show the common pale pink colour typical for transparent erbium(III) compounds.  相似文献   

13.
Cs4[La(NO3)6](NO3) · HNO3: The First Nitric Acid Adduct of a Ternary Alkali Lanthanide Nitrate In the crystal structure of Cs4[La(NO3)6](NO3). HNO3 (monoclinic, P21/c, Z = 2, a = 787.3(2); b = 1353.0(3); c = 1141.8(7) pm; β = 94,37(3)°) La3+ has a coordination number of twelve (six bidentate nitrate ligands). The structure may be viewed at as a layer structure: Layers of the composition [Cs(1)4La2(NO3)12]2?, and [Cs(2)4(NO3)2(HNO3)2]2+ are stacked alternatively in the [100] direction.  相似文献   

14.
New Oxides with the “Butterfly-Motive”: Rb6[Fe2O5] and K6[Fe2O5] Rb6[Fe2O5] and K6[Fe2O5] were obtained for the first time by annealing intimate mixtures of “Rb6CdO4” with CdO (molar ratio 1 : 1.1) and KO0.48 with CdO (molar ratio 5.9 : 1) respectively in closed Fe-cylinders. Determination and refinement of the crystalstructure confirms the space group C2/m (four-circle-diffractometer data). Rb6[Fe2O5]: Ag Kα , 720 out of 1220 Io(hkl), R = 9.68%, Rw = 6.09%; a = 718.9pm, b = 1183.1 pm, c = 695.4pm, β = 95.05°, Z = 2; K6[Fe2O5]: MoKα , 1214 Out of 12141o(hkl), R = 3.20070, Rw = 2.48%, a = 691.21 pm, b = 1142.78pm, c = 665.50pm, β = 93.82°, Z = 2. The binuclear unit [O2FeOFeO2]6? already known to be planar with oxoferrates(II) now was observed to be angular here and closely related to Na6[Be2O5].  相似文献   

15.
The First “Litho-Manganate(V)” with Layer-Structure: Cs2{Li[MnO4]} By heating intimate mixtures of the oxides [CsO1,2, Li2MnO3; Cs: Mn = 2,3 : 1; Ag-Zylinder, 580°C, 62 d] blue-green single crystals of Cs2{Li[VO4]} were obtained for the first time. The new “Litho-Manganate(V)” crystallices orthorhombic (SG: Cmc21) with a = 596.08(7), b = 1202.6(1), c = 816.8(1) pm (Guinier-Simon data), Z = 4. It is isotypic with Cs2{Li[VO4]} [1]. The structure was determined by four-circle-diffractometer data [Mo? Kα , for 496Io(hkl) R = 3.1%, R, = 2.4%], parameters see text. The Madelung Part of Lattice Energie, MAPLE and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, are calculated and disscussed.  相似文献   

16.
Synthesis and Crystal Structure of the Fluoride ino‐Oxosilicate Cs2YFSi4O10 The novel fluoride oxosilicate Cs2YFSi4O10 could be synthesized by the reaction of Y2O3, YF3 and SiO2 in the stoichiometric ratio 2 : 5 : 3 with an excess of CsF as fluxing agent in gastight sealed platinum ampoules within seventeen days at 700 °C. Single crystals of Cs2YFSi4O10 appear as colourless, transparent and water‐resistant needles. The characteristic building unit of Cs2YFSi4O10 (orthorhombic, Pnma (no. 62), a = 2239.75(9), b = 884.52(4), c = 1198.61(5) pm; Z = 8) comprises infinite tubular chains of vertex‐condensed [SiO4]4? tetrahedra along [010] consisting of eight‐membered half‐open cube shaped silicate cages. The four crystallographically different Si4+ cations all reside in general sites 8d with Si–O distances from 157 to 165 pm. Because of the rigid structure of this oxosilicate chain the bridging Si–O–Si angles vary extremely between 128 and 167°. The crystallographically unique Y3+ cation (in general site 8d as well) is surrounded by four O2? and two F? anions (d(Y–O) = 221–225 pm, d(Y–F) = 222 pm). These slightly distorted trans‐[YO4F2]7? octahedra are linked via both apical F? anions by vertex‐sharing to infinite chains along [010] (?(Y–F–Y) = 169°, ?(F–Y–F) = 177°). Each of these chains connects via terminal O2? anions to three neighbouring oxosilicate chains to build up a corner‐shared, three‐dimensional framework. The resulting hexagonal and octagonal channels along [010] are occupied by the four crystallographically different Cs+ cations being ten‐, twelve‐, thirteen‐ and fourteenfold coordinated by O2? and F? anions (viz.[(Cs1)O10]19?, [(Cs2)O10F2]21?, [(Cs3)O12F]24?, and [(Cs4)O12F2]25? with d(Cs–O) = 309–390 pm and d(Cs–F) = 360–371 pm, respectively).  相似文献   

17.
Synthesis, Crystal Structure, and 12Sb-Mössbauer Spectrum of [SbCl2(18-Crown-6)]+SbCl6? The title compound, which has been prepared by the reaction of antimony trichloride and antimony pentachloride in the presence of 18-crown-6 in acetonitrile solution, is characterized by its 121Sb-Mössbauer spectrum and by an X-ray structure determination. Space group P21, Z = 2, 2439 observed unique reflections, R = 0.045, wR = 0.043. Lattice dimensions at ?80°C: a = 780.6(7), b = 1297.5(9), c = 1 278.5(10) pm, β = 100.56(7)°. The structure of [SbCl2(18-crown-6)]+SbCl6? contains cations in which the antimony atom in the first coordination sphere is surrounded in a ?-trigonal-bipyramidal fashion by two oxygen atoms of the crown ether in axial position as well as in the equatorial position by the two chlorine atoms and the lone electron pair.  相似文献   

18.
An Oxostannate of a New Structure Type: Cs4[SnO4] In order to prepare Cs3LiSnO4 by heating of a well ground mixture of the binary oxides [CsO0.67, Li2O, SnO2; Cs:Li:Sn = 3.3:1.0:1.0; 450°C; 28 d; Ni-tube] colourless, monoclinic single crystals of Cs4[SnO4] have been yielded for the first time: space group P21/c with a = 1180.8 pm. b = 728.2 pm, c = 1166,7 pm, β = 111.79°, Z = 4. The crystal structure was solved by fourcycle-diffractometer data [Siemens AED2, 2299 from 2708 I0(hkl), R = 7.0%, Rw = 5.6%], parameters see text. Characteristic for the complicated structure are “isolated” [SnO4]4? tetrahedra. Mean Fictive Ionic Radii, MEFIR, Effective Coordination Numbers, ECoN and the Madelung Part of Lattice Energy, MAPLE, have been calculated.  相似文献   

19.
Colourless, lath‐shaped single crystals of Cs2[B12I12] · 2 CH3CN (monoclinic, C2/m; a = 1550.3(2), b = 1273.2(1), c = 1051.5(1) pm, β = 120.97(1)°; Z = 2) are obtained by the reaction of Cs2[B12H12] with an excess of I2 and ICl (molar ratio: 1 : 2) in methylene iodide (CH2I2) at 180 °C (8 h) and recrystallization of the crude product from acetonitrile (CH3CN). The crystal structure contains quasi‐icosahedral [B12I12]2– anions (d(B–B) = 176–182 pm, d(B–I) = 211–218 pm) which arrange in a cubic closest‐packed fashion. All octahedral interstices are filled with centrosymmetric dimer‐cations {[Cs(N≡C–CH3)]2}2+ containing a diamond‐shaped four‐membered (Cs–N–Cs–N) ring of Cs+ cations and nitrogen atoms of the solvating acetonitrile molecules (d(Cs–N) = 321 pm, 2 ×). The cesium cations themselves actually reside in the distorted tetrahedral voids of the cubic [B12I12]2– packing (d(Cs–I) = 402–461 pm, 10 ×) if one ignores the solvent particles.  相似文献   

20.
Transparent platelet‐shaped green single crystals of the title compound were obtained by the reaction of cesium bromide, praseodymium, sulfur, and red phosphorus in the molar ratio 1:2:8:2 with an excess of CsBr as flux in evacuated silica ampoules at 950 °C for fourteen days. Cs3Pr5[PS4]6 crystallizes monoclinically in the space group C2/c (a = 1627.78(7), b = 1315.09(6), c = 2110.45(9) pm, β = 103.276(5)°; Z = 4). Its crystal structure is different from all the other alkali‐metal containing ortho‐thiophosphates of the lanthanides, since it is not possible to formulate a layer containing the praseodymium centered sulfur polyhedra ([PrS8]13—, d(Pr—S) = 286 — 307 pm) and the isolated [PS4]3— tetrahedra (d(P—S) = 202 — 207 pm, ?(S—P—S) = 104 — 106°). All these tetrahedra are edge‐sharing with the metal polyhedra to build up a framework instead. The coordination sphere of the half occupied (Cs2)+ cations (CN = 10 + 2) can be described as two six‐membered sulfur rings in chair conformation containing a “cesium‐pair” in the middle. In contrast the (Cs1)+ cations are surrounded in the not unusual configuration of tetracapped trigonal prisms (CN = 10, better 10 + 2 as well).  相似文献   

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