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1.
Er3Pd7P4 — Crystal Structure Determination and Extended Hückel Calculations Er3Pd7P4 was prepared by heating the elements (1050°C) and investigated by means of single-crystal X-ray methods. The compound crystallizes in a new structure (C2/m; a = 15.180(3) Å, b = 3.955(1) Å, c = 9.320(1) Å, β = 125,65(1)°; Z = 2) with a three-dimensional framework of Pd and P atoms and with Er atoms in the holes. The Pd atoms are surrounded tetrahedrally, trigonally or linearly by P atoms, which are coordinated by nine metal atoms in the form of a tricapped trigonal prism. Therefore the atomic arrangement of Er3Pd7P4 is related to the structures of ternary transition metal phosphides with a metal: phosphorus ratio of 2:1. Band calculations using the Extended Hückel method show strong covalent Pd? P bonds and weak bonding interactions between Pd atoms with Pd? Pd distances shorter than 2.9 Å.  相似文献   

2.
Preparation and Crystal Structure of Ca5Hg3 and Sr5Cd3 Both the incongruently melting compounds, Ca5Hg3 and Sr5Cd3, have been synthesized from stoichiometric amounts of the pure elements. They crystallize with the Cr5B3 type of structure: space group I4/mcm, Z = 4; Ca5Hg3 (Sr5Cd3): a = 818.9(1) (871.7(1)) pm, c = 1 470.1(3) (1 660.1(3)) pm, c/a = 1.80 (1.90), R = 2.33% (2.97%). The most remarkable fragments are dumbbells X2, which have interatomic distances only slightly longer than the sum of Pauling's covalent radii: Hg? Hg (Cd? Cd) = 306 (298) pm. The structure can be constructed by rhombic dodecahedra as the only constituent moieties. These rhombic dodecahedra are built up by eight Ca (Sr) atoms and six Hg (Cd) atoms and are furthermore centered by an additional Ca (Sr) atom. Along [001] the rhombic dodecahedra share common vertices, but along [110] they are interconnected via common triangular faces. This kind of face sharing is responsible for the short distances obtained between the polyhedra, which leads to the occurrence of the dumbbells mentioned above.  相似文献   

3.
Crystal Structures of SeCl3+SbCl6?, SeBr3+GaBr4?, PCl4+SeCl5?, and (PPh4+)2SeCl42? · 2 CH3CN The crystal structures of the title compounds were determined by X-ray diffraction. SeCl3+SbCl6?: Space group P21/m, Z = 4, structure determination with 1795 observed unique reflections, R = 0.022. Lattice dimensions at ?80°C: a = 940.9, b = 1066.3, c = 1234.9 pm, β = 102.79°. The compound forms ion pairs with the structure of a double octahedron with linked surfaces. SeBr3+GaBr4?: Space group Pc, Z = 2, structure determination with 1461 observed unique reflections, R = 0.058. Lattice dimensions at ?60°C: a = 660.1, b = 655.3, c = 1431.3 pm, β = 101.177°. The compound crystallizes in the SCl3[AlCl4] lattice type. Between the ions there are two relatively short Se … Br? Ga contacts. PCl4+SeCl5?: Space group Ima2, Z = 8, structure determination with 1757 observed unique reflections, R = 0.029. Lattice dimensions at ?50°C: a = 1651.6, b = 1201.2, c = 1166.4 pm. The SeCl5? ions are associated to chains via interionic Se? Cl … Se contacts along the crystallographic c-axis. (PPh4+)2SeCl42? · 2CH3CN: Space group P21/n, Z = 2, structure determination with 2578 observed unique reflections, R = 0.050. Lattice dimensions at ?80°C: a = 1288.5, b = 726.0, c = 2585.8 pm, β = 101.65°. The compound includes planar-tetragonal SeCl42? ions, which almost meet D4h symmetry.  相似文献   

4.
Crystal Structure and Properties of Calcium and Strontium Hexathiodiphosphate(IV), Ca2P2S6 and Sr2P2S6, with a Contribution on Ca5P8 and Pb2P2S6 Ca2P2S6 and Sr2P2S6 were prepared from metal and a mixture of red phosphorus and sulfur (molar ratio M:P:S = 1:1:3) in 2 corundum crucibles inserted in quartz ampullae under vacuum (20 d 900°C). The compounds were obtained as colourless, crystalline powders containing single crystals. They crystallize in the Sn2P2S6 (high temperature form) type structure (P21/c, Z = 2): Ca2P2S6 a = 653.2(2)pm, b = 728.1(2)pm, c = 1110.1(4)pm, β = 124.00(4)°, d = 2.50(2); Sr2P2S6 a = 664.3(2)pm, b = 755.7(3)pm, c = 1139.7(3)pm, β = 124.07(2)°, d = 2.97(2). The anions P2S have staggered confirmation and are arranged with the motif of a cubic close-packing. Sr2+ is coordinated by 8S which form a twofold face-capped trigonal prism and belong to 4P2S. Structure calculations clearly show that Pb2P2S6 also crystallizes in P21/c and not in Pc [1]. Also, Raman- and IR-spectra of Ca5P8 were recorded at 20°C. The stretching vibrations of P were assigned in analogy to those of P2S in alkaline earth hexathiodiphosphates(IV). The range of their frequencies (480 to 340 cm?1) is essentially smaller and shifted to smaller values compared with P2S in Ca2P2S6 and Sr2P2S6 (620 to 390 cm?1). The symmetry of P is not D3d but C2h as in the case of P2S.  相似文献   

5.
Synthesis, Crystal Structure and Spectroscopical Characterization of Palladium(II)‐Diphosphate Pd2P2O7 Pd2P2O7 is synthesized by heating (Tmax = 500 °C) stoichiometric amounts of PdO and phosphoric acid. Using chemical vapour transport experiments (850 °C → 750 °C, addition of PdCl2) Pd2P2O7 was crystallized. Pd2P2O7 adopts its own structure type (C 2/c (No. 15), Z = 4, a = 13,151(2) Å, b = 5,172(1) Å, c = 8,139(1) Å, β = 97,52(1)°, 1160 independent reflections, 55 variables, R1 = 0,021 and wR2 = 0,050). Square‐planar [PdO4]‐units are linked by diphosphate‐groups generating a 3D framework. Within this framework ribbons may be distinguished. Thus Pd2P2O7 might be described as palladium(II)‐[diphosphatopalladate(II)]. The results of various spectroscopic measurements (IR, Raman, UV/VIS, 31P‐MAS‐NMR) are reported and discussed within the context of the crystal structure.  相似文献   

6.
On the Compound Sr7Mn4O15 and Structure Relations to Sr2MnO4 and α-SrMnO3 The “compound” hitherto described as a α modification of Sr2MnO4 is shown to consist of a mixture of SrO and the new monoclinic compound Sr7Mn4O15 crystallizing in the space group P 21/c, a = 681.78(6), b = 962.24(8), c = 1038.0(1) pm, β = 91.886(7)°, Z = 2. Up to 0.3 mm long black crystals were grown from prereacted Sr7Mn4O15, SrO, and SrCl2 at 1350°C in a sealed platinum tube under argon. Its structure is related to α-SrMnO3. It contains layers of cornershared double octahedra [O2/2OMnO3MnO2O1/2]7? parallel to (100). Above 100 K the magnetism of Sr7Mn4O15 follows the Curie Weiss law with Θ ~ -426 K and a moment μeff = 3.62 μB corresponding Mn4+.  相似文献   

7.
Crystal Structure of AlI3 · 2 PI3:P2I5+ AlI4? The crystal structure of the title compound was determined from single crystal X-ray data. P2I5+AlI4? crystallizes in the orthorhombic space group Pbca, a = 1 088.3, b = 1 827.3, c = 2 031.6 pm, V = 4040 · 106 pm3, Z = 8. The P2I5+ and AlI4? ions are connected by weak iodine-iodine bonds (I? I distances between 343.5 and 376.3 pm). The mean P? I and Al? I bond lengths were found to be 240.9 and 252.9 pm respectively.  相似文献   

8.
Caesiumchloropalladate(II)‐hydrates – Two New Compounds with Condensed [Pd2Cl6] Groups We were able to synthesize two caesiumchloropalladate(II)‐hydrates in the CsCl/PdCl2/H2O system by hydrothermal methods. Both compounds show combination of monomeric and dimeric Pd–Cl groups. We characterized the crystal structures by single‐crystal X‐ray diffraction. Cs6Pd5Cl16 · 2 H2O ( I ) crystallizes triclinic in space group type P1 (Nr. 2) with a = 8.972(1) Å, b = 11.359(1) Å, c = 18.168(1) Å, α = 83.61(1)°, β = 76.98(1)°, γ = 76.39(1)° and Z = 2, Cs12Pd9Cl30 · 2 H2O ( II ) monoclinic, space group type C2/m (No. 12) with a = 19.952(1) Å, b = 14.428(1) Å, c = 14.411(1) Å, β = 125.29(1)°, and Z = 2.  相似文献   

9.
Palladium Pnictides of Zirconium and Hafnium with a Metal : Nonmetal Ratio of 2 : 1 The following compounds were prepared by heating the elements in the range of 800°–1100 °C and characterized by means of X‐ray single crystal methods: Zr5Pd9P7 (a = 3.815(1), b = 26.319(5), c = 6.511(1) Å) and Hf5Pd9P7 (a = 3.776(1), b = 26.382(7), c = 6.500(3) Å) are isotypic and crystallize in a new structure type (Amm2; Z = 2). This also applies to ZrPdAs (a = 3.887(1), b = 19.288(6), c = 6.690(2) Å; Pmmn; Z = 10), while ZrPdSb (a = 6.814(1), b = 4.289(1), c = 7.870(2) Å) forms a TiNiSi analogous structure (Pnma; Z = 4). Common feature of all structures is the tetrahedral environment of Pd by X atoms (X: P, As, Sb). The linking of the tetrahedra leads to a PdX framework with holes, in which the Zr and Hf atoms respectively are located. The non‐metal atoms have trigonal prismatic metal coordination with three additional metal atoms outside the rectangular faces of the prisms. This XMe9 polyhedron (Me = metal) is typical for the large family of ternary pnictides with a metal : non‐metal ratio of 2 : 1.  相似文献   

10.
Metal Sulfur Nitrogen Compounds. 20. Reaction Products of PdCl2 and Pd(CN)2 with S7NH. Preparation and Structure of the Complexes [Ph6P2N][Pd(S3N)(S5)] and X[Pd(S3N)(CN)2] X = [Me4N]+, [Ph4P]+ With PdCl2 and [Ph6P2N]OH S7NH forms the complex salt [Ph6P2N][Pd(S3N)(S5)], which could be isolated in two modifications (α- and β-form). The α-form is triclinic, a = 9.347(4), b = 14.410(8), c = 15.440(11) Å, α = 76.27°(5), β = 77.06°(4), γ = 76.61α(4), Z = 2, space group P1 . The β-form is orthorhombic, a = 9.333(2), b = 17.659(4), c = 23.950(6) Å, Z = 4. The structure of the metal complex is the same in the two modifications. One S3N? and one S52? are coordinate as chelate ligands to Pd. From S7NH, Pd(CN)2, and XOH X = [(CH3)4N]+ and [(C6H5)4P]+ the salts X[Pd(S3N)(CN)2] were formed. The (CH3)4N-salt is isomorphous with the analogous Ni compound described earlier, the (C6H5)4P-salt is triclinic, a = 9.372(4), b = 10.202(5), c = 13.638(6) Å, α = 86.36α(4), β = 85.66°(4), γ = 88.71°(4), Z = 2, space group P1 . One S3N? chelate ligand and two CN? ions are bound to Pd. In all these complexes the coordination of Pd is nearly square planar.  相似文献   

11.
(NH4)2PO3H, H2O crystallizes in the monoclinic system, space group P21/c, with a = 6.322(1) Å, b = 8.323(1) Å, c = 12.676(1) Å, β = 98.84(1) and Z = 4. The structure was refined to R = 0.022 based on 853 independent X-Rays intensities. Improved dimensions of the tetrahedral PO3H2? ion have been obtained: P?H = 1.34(2) and P?O = 1.514(2) Å. The geometry of this ion is compared with that of PO3F2? and SO32? ions and we find a decrease of the volume: VF? > VH+ > Vlone pair.  相似文献   

12.
CsPdCl3 – A Compound with Isolated [Pd2Cl6] Groups and an Inorganic Cation The crystal structure of CsPdCl3 has been characterized by X-ray powder diffraction methods. Meanwhile it was possible to isolate single crystals and to confirm the structure by single crystal X-ray investigations. CsPdCl3 crystallizes orthorhombic in space group Ibam (No. 72) with a = 13.724(1), b = 10.579(1), c = 8.499(1) Å, and Z = 8. CsPdCl3 is a compound with a dinuclear [Pd2Cl6]2– group and a cesium cation. Formerly such groups are only found in combination with large “organic” cations so far.  相似文献   

13.
Synthesis and Crystal Structure of the Adducts [DB-18C6] · CH3CN · CH3CSOH and [DC-18C6](CH3CSOH)2 as well as of the Salt-like Compounds [Cs(B-15C5)2]CH3CSS and [Cs(DB-18C6)]2S5(DMF)21) The reaction products of crown ethers, cesium, and sulfur in aprotic solvents like acetonitrile and dimethylformamide strongly depend on the reaction conditions. Using CH3CN as a solvent, sometimes neutral host-guest adducts crystallize only, e.g., [dibenzo-18C6] · CH3CN · CH3CSOH (monoclinic, S. G. P21/c, Z = 4, a = 9.73(1) Å, b = 22.03(1) Å, c = 11.86(1) Å, β = 91.8(1)°) or [dicyclohexyl-18C6](CH3CSOH)2 (monoclinic, S. G. P21/n, Z = 2, a = 7.75(1) Å, b = 10.32(1) Å, c = 17.73(1) Å, β = 95.7(1)°). The monothioacetic acid, CH3CSOH, must be regarded as the first product of the hydrolysis of CH3CN. Furthermore, another product of this kind of hydrolysis, CH3CSSH, is obtained too. Therefore, we also obtain the salt-like compound [Cs(benzo-15C5)2]CH3CSS (monoclinic, S. G. C2/c, Z = 4, a = 16.05(1) Å, b = 16.73(1) Å, c = 13.11(1) Å, β = 106.3(1)°). If the solvent DMF is used, the pentasulfide [Cs(dibenzo-18C6)]2S5(DMF)2 crystallizes (monoclinic, S. G. P21/n, Z = 4, a = 14.79(1) Å, b = 14.24(1) Å, c = 25.74(1) Å, β = 92.7(1°. The S52? anions show the cis-conformation.  相似文献   

14.
Crystal Structures of Acid Hydrates and Oxonium Salts. XX. Oxonium Tetrafluoroborates H3OBF4, [H5O2]BF4, and [H(CH3OH)2]BF4 The crystal structures of three oxonium tetrafluoroborates were determined. H3OBF4, oxonium tetrafluoroborate proper, is triclinic with space group P1 , Z = 2 and the unit cell dimensions a = 4.758, b = 6.047, c = 6.352 Å and α = 80.40, β = 79.48, γ = 88.25° at ?26°C. Cations H3O+ and anions BF4? are linked by hydrogen bonds O? H…?F into ribbons of condensed rings. In [H5O2]BF4 (diaquohydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 6.584, b = 9.725, c = 7.084 Å, β = 95.15° at ?100°C) the hydrogen bond in the cation H5O2+ is 2.412 Å short, asymmetric and approximately centered and the linking of cations and anions three-dimensional. In [H(CH3OH)2]BF4 (Bis(methanol)hydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 5.197, b = 14.458, c = 9.318 Å, β = 94.61° at ?50°C) the cation [H(CH3OH)2]+ is characterized for the first time in a crystal structure with an again very short (2.394 Å), asymmetric and effectively centered hydrogen bond. By further hydrogen bonds cations and anions form only dimers of the formula unit of centrosymmetric cyclic structure.  相似文献   

15.
New compounds, Sr2Ga(HPO4)(PO4)F2 and Sr2Fe2(HPO4)(PO4)2F2, have been prepared by hydrothermal synthesis (700°C, 180 MPa, 24 h) and characterized by single-crystal X-ray diffraction. Sr2Ga(HPO4)(PO4)F2 crystallizes in the monoclinic space group P21/n with a = 8.257(1) Å, b = 7.205(1) Å, c = 13.596(2) Å, β = 108.02(1)°, V = 769.2(2) Å3 and Z = 4 and Sr2Fe2(HPO4)(PO4)2F2 in the triclinic space group P21/n with a = 8.072(1) Å, b = 8.794(1) Å, c = 8.885(1) Å, α = 102.46(1)°, β = 115.95(1)°, γ = 89.95(1)°, V = 550.6(1) Å3 and Z = 2. Structures are both based on different sheets involving corner-linkage between octahedra and tetrahedra. The sheets are linked by Sr2+ cations. Structural relationships exist between the descloizite mineral and the title compounds.  相似文献   

16.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of the Linkage Isomeric Chlororhodanoiridates(III) trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? By treatment of Na2[IrCl6] with NaSCN in 2N HCl the linkage isomers trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. X-ray structure determinations on single crystals of trans-(n-Bu4N)3[IrCl2(SCN)4] ( 1 ) (monoclinic, space group P21/a, a = 18.009(4), b = 15.176(3), c = 23.451(4) Å, β = 93.97(2)°, Z = 4) and trans-(Me4N)3[IrCl2(NCS)(SCN)3] ( 2 ) (monoclinic, space group P21/a, a = 17.146(5), b = 9.583(5), c = 18.516(5) Å, β = 109.227(5)°, Z = 4) reveal the complete ordering of the complex anions. The via S or N coordinated thiocyanate groups are bonded with Ir? S? C angles of 105.7–109.7° and the Ir? N? C angle of 171.4°. The torsion angles Cl? Ir? S? C and N? Ir? S? C are 3.6–53.0°. The IR and Raman spectra of ( 1 ) are assigned by normal coordinate analysis using the molecular parameters of the X-ray determination. The valence force constants are fd(IrS) = 1.52 and fd(IrCl) = 1.72 mdyn/Å.  相似文献   

17.
Mixtures of strontium and mercury in molar ratios of 7:3 have been annealed for 20 days at 520°C. From the pure product Sr3Hg2 single crystals have been obtained. Sr3Hg2 crystallizes in the U3Si2 type of structure (space group P4/mbm); the cell constants are a = 8.883 (2) Å and c = 4.553(1) Å. All of the Hg atoms are involved in Hg2 dumbbells with Hg? Hg distances of 3.41 Å.  相似文献   

18.
Pentacalcium Hexaphosphahypodiphosphate, Ca5P8, a Compound with Isolated Anions P810? in the Staggered Ethane Conformation Ca5P8 is prepared from calcium and red phosphorus in a molar ratio 5:8 in argon atmosphere in corundum crucibles inserted in quartz ampullae (3.5 d 1 000°C). It is a red-brown powder which is hydrolyzed by moisture. Single crystals are formed from powder at 1 100°C within 60 d. Ca5P8 crystallizes in a new structure type (mC26) with isolated anions P810? in staggered conformation: C2/m (no. 12); a = 689.9(4) pm, b = 1 188,3(4) pm, c = 748.4(3) pm, β = 108.25(2)°, Z = 2; d = 2.56(1). Ca5P8 is the first compound containing polyphosphide anions with fourfold and single bonded phosphorus atoms (formally P+ and P2?, resp.). The cations Ca2+ are arranged in a distorted cubic close-packing. The centers of the polyphosphide anions replace in an ordered way one third of Ca2+ in every second layer. The terminal P atoms occupy all octahedral interstices, so that P810? is coordinated by 18 Ca2+ in form of a cuboctahedron with capped squaric faces.  相似文献   

19.
Metastable Compounds of Rare Earth Oxides. About Sr3Pr4O9 and Sr3La2Sm2O9 with a Remark about SrPr2O4 Sr3Pr4O9 (A) and Sr3La2Sm2O9 (B) are for the first time prepared and investigated by X-ray single crystal work. Both compounds crystallize with monoclinic symmetry (space group Cs4? Cc, Z = 4) with (A) a = 11.468; b = 7.262; c = 13.218 Å; β = 115.61°, (B) a = 11.518; b = 7.263; c = 13.290 Å; β = 115.61°. (A) and (B) are metastable with high disorder in the metal positions. All of the metal positions are occupied with a statistical distribution of Sr2+ and Ln3+. (A) decomposes in the hitherto unknown compound SrPr2O4. It belongs to the calciumferrite type compounds.  相似文献   

20.
Sr3(BS3)2 and Sr3(B3S6)2: Two Novel Non‐oxidic Chalcogenoborates with Boron in a Trigonal‐Planar Coordination The thioborates Sr3(BS3)2 and Sr3(B3S6)2 were prepared from strontium sulfide, amorphous boron and sulfur in solid state reactions at a temperature of 1123 K. In a systematic study on the structural cation influence on this type of ternary compounds, the crystal structures were determined by single crystal X‐ray diffraction. Sr3(BS3)2 crystallizes in the monoclinic spacegroup C2/c (No. 15) with a = 10.187(4) Å, b = 6.610(2) Å, c = 15.411(7) Å, β = 102.24(3)° and Z = 4. The crystal structure of Sr3(B3S6)2 is trigonal, spacegroup R3¯ (Nr. 148), with a = 8.605(1) Å, c = 21.542(4) Å and Z = 3. Sr3(BS3)2 contains isolated [BS3]3— anions with boron in a trigonal‐planar coordination. The strontium cations are found between the layers of orthothioborate anions. Sr3(B3S6)2 consists of cyclic [B3S6]3— anions and strontium cations, respectively.  相似文献   

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