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1.
Ca3Cl2CBN, a Compound with the New CBN4? Unit The new compound Ca3Cl2CBN was obtained from the reaction of Ca and CaCl2 with CaCN2, B and C or with BN and C, in sealed tantalum containers at 900°C. The crystal structure is related with the structure of Ca3Cl2C3 whereas the C34? units (C2v symmetry) are substituted by isoelectronic CBN4? anions (Cs symmetry): Ca3Cl2CBN, Pnma, a = 1 386.7(9) pm, b = 384.7(3) pm, c = 1 124.7(6) pm, Z = 4; R = 0.055, Rw = 0.036 for 380 independent intensities. The CBN4? units are located between layers of Ca2+ that are interconnected by Cl?. The bond angle (C? B? N) is 176° and bond distances are dC? B = 144 pm and dB? N = 138 pm, respectively.  相似文献   

2.
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   

3.
Structures with AIB2? and BaAl4?type Units. I The Compounds Sr4Pd5P5 and Sr2Pd3P3 Sr4Pd5P5 (Cmcm, a = 4.177(1) Å, b = 31.377(5) Å, c = 8.581(2) Å, Z = 4) und Sr2 Pd3P3(Pmmm, a = 4.199(1) Å, b = 4.212(1) Å, c = 34.227(4) Å, Z = 4) have been prepared by heating the elements. Both structures contain exclusively units characteristic for the AIB2? and BaAl4?type. The ratio between isolated P-atoms and P2?pairs is interpreted with an ionic splitting of the formulas.  相似文献   

4.
The Metal-Rich Titanium Selenide Ti9Se2 The new compound Ti9Se2 has been prepared as hitherto most metal-rich phase in the system titanium-selenium. It crystallizes in the orthorhombic space group Pbam (No. 55) with a = 691.7(2), b = 1 550.5(9), c = 345.4(2) pm. The structure consists of [Ti9]-strings which are described within the concept of condensed clusters. The Se atoms are coordinated by tricapped trigonal prisms of Ti atoms.  相似文献   

5.
Reaction of Telluriumhexafluoride and Trimethylamine, Structures of the TeF5? and SeF5? Anions The reaction of TeF6 and (CH3)3N is of the redox kind, resulting in reduction of tellurium: X-ray single crystal analysis reveals the compounds (CH3)2N? CH2? N(CH3)2+TeF5? and [(CH3)3NH+]5(TeF5?)3(HF2?)2. By comparison with published data it can be shown that this mixture is identical to previously published [(CH3)3N]2TeF6. The latter was supposed to be one of the few examples of tellurium in a coordination state of eight. (CH3)4N+TeF5? and (CH3)4N4SeF5? are obtained and their structure is investigated by single crystal x-ray methods also. The anions SF5?, SeF5? and TeF5? are discussed in terms of weak interactions.  相似文献   

6.
On the Reaction of Tellurium with Tungsten Halides: Synthesis and Crystal Structure of Te7WOCl5, a Compound with a Polymer Tellurium Cation The reaction of tellurium with WOCl4 in the presence of a large excess of WCl6 in a sealed evacuated glass ampoule at 150°C yields beside the main product Te8(WCl6)2 a small amount of Te7WOCl5. The crystal structure determination (orthorhombic space group Pcca, lattice parameters at 173 K: a = 2 596.5(9) pm, b = 810.0(3) pm, c = 775.7(2) pm) shows that Te7WOCl5 is built of one-dimensional band shaped polymeric tellurium cations, one-dimensional associated pyramidal WOCl4? anions and of isolated Cl? anions. Te7WOCl5 can thus be formulated as [Te72+]n [WOCl4?]n (Cl?). The structure is closely related but not isotypic to the bromine containing analogue Te7WOBr5. The difference between the two structures lies in different directions of the polar [WOX4?]n chains (X = Cl, Br). The strongly elongated thermal ellipsoid of one tellurium atom is shown to be caused by thermal vibration by determing the crystal structure of Te7WOCl5 at three different temperatures (223, 173 and 123 K). All displacement parameters of all atoms can be extrapolated to zero for 0 K.  相似文献   

7.
Titanium Tetrafluoride – a Surprising Simple Column Structure For the first time single crystals of TiF4 have been obtained by solvothermal decomposition of (O2)2Ti7F30 in anhydrous HF. The colourless, transparent needles crystallize orthorhombic in spacegroup Pnma–D (No. 62) with a = 2 281.1, b = 384.8, c = 956.8 pm, Z = 12. The new type of structure is dominated by isolated columns of corner-linked TiF6-octahedra.  相似文献   

8.
New Alkylchlorosulfonium Salts and Crystal Structure of Diethylchlorosulfonium-Hexachloroantimonate (C2H5)2SCl+SbCl6? We describe the preparation and spectroscopic characterization of Dialkylchlorosulfonium-Hexachloroantimonates R2SCl+SbCl6? (R = C2H5, i-C3H7) and the crystal structure of Diethylchlorosulfonium-Hexachloroantimonate (C2H5)2SCl+SbCl6? at 172(1) K. The salt crystallize in the orthorhombic space group P212121 with a = 980.4(13) pm, b = 1010.6(8) pm, c = 1492.8(14) pm with four formula units per unit cell.  相似文献   

9.
Ga8Ir4B – a Gallium Iridium Boride with isolated, nearly square planar Ir4B Groups in a Structure derived from the CaF2 Type The new compound Ga8Ir4B (tetragonal, I41/acd, a = 853.69(2) pm, c = 2 105.69(6) pm, Z = 8, 614 reflections, 31 parameters, R = 0.034) was prepared by reaction of the elements at 1 100°C. The structure is derived from the CaF2 type. It contains isolated Ir4B groups with boron in an unusual, nearly square planar coordination.  相似文献   

10.
Polynuclear Complexes with Fe? As, Fe? Sb, and Fe? Bi Frameworks The anionic iron clusters Fe3(CO)112? and Fe4(CO)132? were reacted with compounds EX3 and with organic derivatives REX2 and R2EX of the elements arsenic, antimony, and bismuth. Commonly redox and cluster degradation reactions were observed. The new complexes [(CO)4Fe? AsMe2? Fe(CO)4]?, [HFe3(CO)9(mu;3-SbBut)]?, [Fe3(CO)10 (mu;3-Sb)]?, and [Fe3(CO)10(mu;3-Bi)]? were formed and isolated as their PPN salts. The Fe? As? Fe complex was identified by a structure determination, the other complexes were identified by their spectra.  相似文献   

11.
Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 53. Preparation, Properties, and Vibrational Spectra of the Cage Anions P113? and As113? The Zintl-phases M3X11 (M = Na, K, Rb, Cs; X = P, As) are prepared from the elements or from M3X7 and X. The compounds undergo a first-order phase transition from the crystalline to the plastically crystalline state. Unit cell and space group of both modifications and the transition temperature Tc are determined. The vibrational spectra of the crystalline compounds and the Raman spectrum of the P113? anion in en-solution as well are measured. The assignment of the frequencies is given, based on the 32-D3 symmetry of the X113? cage anion. Normal coordinate analysis is carried out in terms of Cartesian coordinates to avoid the problem of redundancies in using internal coordinates. The force constants [mdyn Å?1] obtained for the characteristic bonds r, s, and t are: f = 1.34, f = 1.20, f = 1.08; f = 1.1, f = 0.91. Normal vibrations and the potential energy distribution (PED) are discussed.  相似文献   

12.
Synthesis and Structure of Li3RhH6 — a Ternary Hydride with Isolated [RhH6]3? Octahedra The ternary rhodium hydride Li3RhH6 was synthesized by the reaction of lithium hydride with rhodium under a hydrogen pressure of 80 bar. X-ray investigations on powdered samples and an elastic neutron diffraction experiment on the deuterated compound led to the complete structure determination (space group: Pnma, Z = 4). The atomic arrangement is isotypic to the Na3RhH6 structure type. The crystal structure contains isolated [RhH6]3? octahedra, which are separated by the lithium ions.  相似文献   

13.
Ba[CoN]: A Low-Valency Nitridocobaltate with Angled Chains [CoN2/22?] Ba[CoN] is prepared by reaction of barium and cobalt (molar ratio Ba : Co = 1 : 2.5) in tantalum crucibles at 870°C with flowing nitrogen (1 atm) within a period of 96 h. After cooling down to room temperature (24°C/h) black single crystals of the ternary phase with a platy habit are obtained (orthorhombic, Pnma; a = 959.9(2) pm, b = 2 351.0(3) pm, c = 547.6(2) pm; Z = 20). The crystal structure of Ba[CoN] contains angled (planar) chains [CoN2/22?] which run along the [010]-direction (N? Co? N[°]: 178.5(5), 179.6(6), 180.0; Co? N? Co[°]: 82.9(6), 84.2(5), 177.1(8); Co? N[pm]: 174.6(12), 177.2(12), 181.9(13), 184.3(13), 187.1(12)). Nitrogen is in an octahedral coordination (N Ba4Co2) and is arranged in a distorted cubic close packing. Barium occupies one half of the tetrahedral holes (Ba? N[pm]: 274.8(16) ? 308.2(12)). The cis-positions of the Co-atoms at the nitrogen coordination-octahedra cause short Co? Co contacts within the chains [CoN2/22?]. Through this, Co2-units (Co? Co[pm]: 247.8(4); bridged by nitrogen) and linear Co3-groups (Co? Co [pm]: 245.5(2); Co? Co? Co[°]: 180.0; bridged by nitrogen) alternate along the chains. The crystal structure of Ba[CoN] is closely related to the Ba[NiN] type structure.  相似文献   

14.
PdSCl, a Molecular Palladium(II) Disulfidechloride with Octanuclear Pd8(S2)4Cl8 Groups and with Tetra Metal-coordinated bridging Disulfide Groups Black crystals of PdSCl have been obtained by reaction of Pd with S2Cl2 in closed quartz ampoules at 200°C. The compound is to be formulated as a Palladium(II)-disulfidechloride consisting of Pd8(S2)4Cl8 molecules with approximately D4h symmetry. In the octanuclear complexes Pd atoms form a cube, where bridging disulfide groups are found in front of 4 faces and μ2?bridging Cl atoms on 8 edges. In the monoclinic crystal structure (a = 8.763(2) Å; b = 9.082(2) Å; c = 13.662(4) Å; β = 91.748(23)°; V = 1086.8 Å3; Z = 16 PdSCl; Space gr. P21/n) the molecules form a cubic closed arrangement.  相似文献   

15.
Contributions on the Thermal Behaviour of Anhydrous Phosphates. VII Preparation, Structure, and Thermal Behaviour of Orthorhombic NbPO5–δ By a chemical vapour transport in a temperature gradient (e.g. 1000° → 9000°C) it is possible to prepare the already known forms of NbPO5 and a new phase as single crystals. Using I2 or NH4Cl as transport agents α?NbPO5 was obtained as colourless crystals, which enabled a refinement of the already known tetragonal crystal structure to R = 1.73%. The dark blue crystals of the up to now unknown orthorhombic phase could only be prepared under reducing conditions (by adding NbP). Their crystall structure is related to monoclinic β-NbPO5 (single crystall investigation, space group Pna21; a = 11.2875 Å; b = 6.6296 Å; c = 5.2871 Å; Z = 4; R = 3.17%), but the crystals are deficient in oxygen according to NbPO5?δ recognizable by the dark blue colour. When NbPO5?δ (orthorhombic) is ground in an agate mortar NbPO5?δ (monoclinic) is formed, which has the already known structure of β-NbPO5. By heating (340°C) a reversible transformation from NbPO5?δ (monoclinic) to NbPO5?δ (orthorhombic) takes place. This is isostructural to WPO5 and also to an orthorhombic modification of (colourless) NbPO5, which we also could observe above 340°C.  相似文献   

16.
ACl3 · 2NH3 – a Compound with the Crystal Structure of a Tetraammine Dichloroaluminiumtetrachloroaluminate – [AlCl2(NH3)4]+[AlCl4]? Ammoniates of aluminiumchloride AlCl3 · xNH3 are in discussion as starting materials for the synthesis of aluminiumnitride. Therefore the reactions of melts of monoamminealuminiumchloride with ammonia were investigated. They react at 150°C within 10 min with one mole of ammonia to the diammoniate, [AlCl2(NH3)4]+[AlCl4]?. The pure compound can be obtained by sublimation at 200°C in vacuumline apparatus. X-ray structure determination on [AlCl2(NH3)4]+[AlCl4]? was carried out: see “Inhaltsübersicht”.  相似文献   

17.
Synthesis and Structure of Hexa-t-butyl-1,4-dichloro-1,4-distanna-2,3,5,6,7,8-hexaphosphabicyclo[2.2.2]octane – a New Cage Compound with the Sn(P2)3Sn Skeleton The reaction of the diphosphide K2[(tBuP)2] 1 with SnCl4 leads by a redox process mainly to (tBuP)3,4 and other sideproducts. However, at the same time a threefold [2 + 1]-cyclocondensation reaction takes place yielding the new cage compound hexa-t-butyl-1,4-dichloro-1,4-distanna-2,3,5,6,7,8-hexaphosphabicyclo[2.2.2]octane, ClSn(tBuP? PtBu)3SnCl 2 . 2 could be obtained in a pure form and characterized 31P and 119Sn NMR spectroscopically; 2 was also characterized by a single crystal structure analysis.  相似文献   

18.
Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 58. Tetrabariumtriphosphide, Ba4P3: Preparation and Crystal Structure Ba4P3 is obtained from the elements in the molar ratio 4:3 or by reaction of Ba3P2 and Ba5P4 in the molar ratio 1:1 (steel ampoules with inner corundum crucibles; 1 490 K). The greyish black, easily hydrolysing compound crystallizes in a new structure type oP56. The structure shows two crystallographically independent dumbbells P24? (d(P? P) = 225 and 232 pm) and isolated ions P3? corresponding to (Ba2+)8(P24?)4(P3?)4. The partial structure of the Ba atoms forms a complex network of trigonal prisms with tetrahedral and square pyramidal holes, as well as polyhedra with 14 faces (CN 10) which are icosahedron derivatives. The P3? anions center trigonal prisms and the 14 face polyhedron. The P-atoms of the P24? dumbbells center neighboring trigonal prisms with common square faces. (Pbam (no. 55); a = 1 325.4(2) pm, b = 1 256.2(2) pm, c = 1 127.3 pm; Z = 8).  相似文献   

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