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1.
New Ternary Phosphides and Arsenides of Cesium and Element of the 8th Transition Metal Group In the ternary systems Cesium/8th transition metal group/5th main group some new compounds were found and investigated. By single crystal measurements CsRh2P2 was found to crystallize in the space group 14/mmm with the lattice constants a = 390.11 pm and c = 1429.36 pm. The new compounds with the formula CsM2X2 (M = Fe, Co, Ru, Rh, Ir; X = P or As) crystallize in the ThCr2Si2-type structure, compounds of the formula Cs2MX2 (M = Ni, Pd, Pt; X = P or As) can be placed in a line with the K2PdP2-type structure.  相似文献   

2.
Sulfur(IV) Compounds as Ligands. II. The Crystal and Molecular Structure of Pentacarbonyl--(sulfur dioxide)chromium The structure of pentacarbonyl(sulfurdioxide)chromium ( 1 ) has been determined from single crystal X-ray data. The compound crystallizes with eight formula units in the rhombic unit cell (space group Pbn21) of the dimensions a = 657.8(2) pm, b = 1245.2(4) pm, c = 2177.4(5) pm (at 180 K). The sulfur dioxide is η1-coplanar coordinated, the Cr? S distance is 219 pm, the shortest bond reported so far between chromium(0) and sulfur. The Cr? C(ax) bond (189 pm) was found only marginally shorter than the Cr? C(eq) bonds (190 pm) providing proof of the high π-acceptor capacity of SO2.  相似文献   

3.
Preparation and Crystal Structure of New AM2X2 Compounds in the Systems Earthalkali Metal/Platinum Metal/Germanium . Four new ternary compounds in the systems earthalkali metal/platinum metal/germanium have been prepared and characterised by single crystal X-ray investigation. BaRu2Ge2 crystallizes orthorhombically, space group Fddd, a=634.4(1) pm, b=1 056.5(3) pm, c=1 273,1(3) pm. SrRu2Ge2 (a=430.6(1) pm, c=1 030.3(2) pm), BaRh2Ge2 (a=418.9(5) pm, c=1 175.7(10) pm) and SrRh2Ge2 (a=418.3(3) pm, c=1 071.8(6) pm) crystallize in the ThCr2Si2-type structure (tetragonal, space group I4/mmm).  相似文献   

4.
Intercalation of Metal Nitrates in Graphite. IV. Reaction of Anhydrous Copper (II) Nitrate with Graphite By heating of Cu(NO3)2 and Cu(NO3)2 · N2O4 with graphite (160–200°C, 1–8 d) samples of stage 4, 5, and 6 of Cu(NO3)2 graphite were obtained, which were characterized by X-ray powder diffraction and chemical analysis. 4th stage: Ic = 2030 pm, C:Cu ≈ 40:1. 5th stage: Ic = 2365 pm, C:Cu ≈ 50:1. 6th stage: Ic = 2700 pm, C:Cu ≈ 60:1. The intercalate thickness was found to be 690 pm. Heating with Cl2 yields the corresponding stages of CuCl2 graphite.  相似文献   

5.
Hydroxo Compounds. 9. Barium Oxohydroxostannate(II) Ba[SnO(OH)]2 The pale yellow barium hydroxostannate(II), to which different stoichiometries have been assigned in the past, is now identified doubtlessly as Ba[SnO(OH)]2. The compound crystallizes in the monoclinic space group P21 (a = 759.4(2) pm, b = 576.2(1) pm, c = 717.4(2) pm, β = 107.67(2)°, Z = 2, R = 0.038, 645 Ihkl) and exhibits a typical layer structure. Ba[SnO(OH)]2 contains a new structural element in tin(II) chemistry, which is a one dimensional polyanion [SnO(OH)]? with syndiotactical conformation. In the context with the structures of two Na-hydroxostannates(II) which were characterized recently, the polyanion can be looked at as an intermediate condensation product of a (topotactical ?) reaction to SnO which all known hydroxostannates(II) undergo.  相似文献   

6.
Transition Metal Complexes of P-rich Phosphanes and Silyphosphanes. III. Complex Compounds (t-Bu)3P9 · Cr(CO)5 and (t-Bu)3P9 · 2 Cr(CO)5 Derived from Nonaphosphane (3) (t-Bu)3P9 The reaction of (t-Bu)3P9 1 with Cr(CO)5 · THF in a molar ratio of 1:1 yields (t-Bu)3P9 · Cr(CO)5 2 (yellow crystals) with the Cr(CO)5 group coordinated to an equatorial P atom of the P9 skeleton. In the reaction of 1 with 2 moles of Cr(CO)5 · THF the complex product (t-Bu)3P9 · 2 Cr(CO)5 3 is formed with the second Cr(CO)5 group linked to a basal P atom. Evidence for this comes from 31P NMR spectra as well as from crystal structure determinations of 2 and 3.2 crystallizes in the space group P21/n with a = 1012,9(2) pm, b = 2961,9(4) pm, c = 983,2(2) pm, β = 101,41(2)° and Z = 4 formula units. 3 crystallizes on the space group Pbcn with a = 2675,8(8) pm, b = 1222,4(2)pm, c = 2212,3 pm and Z = 8. In 2 and 3 the equatorial P atoms opposite to the P2 dumbbell are complexed. The further complexation in 3 takes place at a basal P atom in Z-arrangement. The distances d(P Cr) are 243.5(1) pm and 240.5(1) pm and 240.5(1) pm for the equatorial P atoms in bf 2 and 3, respectively. For the basal P atom is 3 the distance in 235.7 pm. The P P distance range from 217.5 to 223.0 pm with the shorter ones at the bridgehead atom and the longer one at the P2 dumbbell. The structures are discussed with that of the free ligand.  相似文献   

7.
Ternary Compounds of Lithium with Yttrium, Lanthanum, or Neodymium and Elements of the Fifth Main Group in a “Filled” CaAl2Si2-type Structure Formation and crystal structure of ternary compounds with lithium and yttrium, lanthanum or neodymium and elements of the fifth main group of the composition ALi3X2v (A = Y, La, Nd; Xv = P, As, Sb, Bi) are reported. Crystal structure determination by X-ray and neutron diffraction methods show that the compounds crystallize in a ?filled”? CaAl2Si2 structure. Two Li atoms of the formula occupy the Al sites in distorted tetrahedral Xv holes of the lattice, the slightly distorted octahedral holes of the Xv atoms are filled with A and the third Li atom.  相似文献   

8.
Preparation and Crystal Structure of Cs2Sb4S7 The first thioantimonite of Cesium has been synthesized and its crystal structure determined. The substance crystallizes monoclinic with spacegroup P21/c. The lattice constants are a = 1111.2(5) pm, b = 1227.1(5) pm, c = 1163.7(5) pm and ß = 97.60(5)°. There are four formula units in the unit cell. Sb–S chains are formed by trigonal SbS3 pyramids and ψ-trigonal SbS4 bipyramids.  相似文献   

9.
New Ternary Arsenides of Cesium with 8b-Elements Cs2PdAs2 was prepared from the elements. It is isotypic with K2PdAs2 (A2MX2) and crystallizes orthorhombically, space group Cmcm, with the following constants: a = 706.8(4) pm; b = 1476.6(7) pm; c = 636.6(3) pm. The structure is characterized by MX2-zigzag-ribbons surrounded by channel-like arranged alkali atoms. The new ternary compounds CsRu2As2 and CsRh2As2 are isotypic with ThCr2Si2 (inferred from powder photographs).  相似文献   

10.
On the Reaction of HCl with HF/SbF5 and the Crystal Structure of SbCl3F2 The reaction of HCl in HF/SbF5 solution at ?78°C yields H2F+SbClF5?. At ?40°C formation of SbCl3F2 was observed, which crystallizes in the tetragonal space group I-4 with a = 1 281.6(5) pm, c = 758.1(6) pm with 8 formula units per unit cell. The structure contains cis-fluorine-bridged tetramers, in which Sb has a distorted octahedral coordination.  相似文献   

11.
Quaternary Cesium Copper(I) Lanthanoid(III) Selenides of the Type CsCu3M2Se5 (M = Sm, Gd — Lu) By oxidation of mixtures of copper and lanthanoid metal with elemental selenium in molar ratios of 1 : 1 : 2 and in addition of CsCl quaternary cesium copper(I) lanthanoid(III) selenides with the formula CsCu3M2Se5 (M = Sm, Gd — Lu) were obtained at 750 °C within a week from torch‐sealed evacuated silica tubes. An excess of CsCl as flux helps to crystallize golden yellow or red, needle‐shaped, water‐resistant single crystals. The crystal structure of CsCu3M2Se5 (M = Sm, Gd — Lu) (orthorhombic, Cmcm, Z = 4; e. g. CsCu3Sm2Se5: a = 417.84(3), b = 1470.91(8), c = 1764.78(9) pm and CsCu3Lu2Se5: a = 407.63(3), b = 1464.86(8), c = 1707.21(9) pm, respectively) contains [MSe6]9— octahedra which share edges to form double chains running along [100]. Those are further connected by vertices to generate a two‐dimensional layer parallel to (010). By edge‐ and vertex‐linking of [CuSe4]7— tetrahedra two crystallographically different Cu+ cations build up two‐dimensional puckered layers parallel to (010) as well. These sheet‐like structure interconnects the equation/tex2gif-stack-3.gif{[M2Se5]4—} layers to create a three‐dimensional network according to equation/tex2gif-stack-4.gif{[Cu3M2Se5]}. Thus empty channels along [100] form, apt to take up the Cs+ cations. These are surrounded by eight plus one Se2— anions in the shape of (2+1)‐fold capped trigonal prisms with Cs—Se distances between 348 and 368 pm (8×) and 437 (for M = Sm) or 440 pm (for M = Lu), respectively, for the ninth ligand.  相似文献   

12.
Single Crystal X-Ray Analysis of Compounds with Covalent Metal—Metal Bonds. IV. Molecular and Crystal Structure of Mn2(CO)8[μ-Sn(Br) Mn(CO)5]2 Mn2(CO)8[μ-Sn(Br)Mn(CO)5]2 crystallizes in the monoclinic crystal system (a = 881.7 pm; b = 1237.6 pm; c = 1551.1 pm und β = 63.54°) in the space group P21/n with two formula units in the cell. The structure was solved by means of 2601 symmetrically independent reflections using the heavy atom method. The central molecule fragment of Mn2(CO)8 · [μ-Sn(Br)Mn(CO)5]2 consists of a planar Mn2Sn2 rhombus with a Mn? Mn-bond (Mn? Mn = 308.6(1) pm) across the metal ring. Besides the bonds to both Mn ring atoms each Sn(IV) atom has a terminal bond to a Br and Mn(CO)5 ligand, building up a distorted tetrahedron around the Sn(IV) atom. The terminal ligands in Mn2(CO)8[μ-Sn(Br)Mn(CO)5]2 are in transposition with respect to the ring. The mean values for the remaining bond distances are: Sn? Mn = 263.0(1) pm; Sn? Br = 255.4(1) pm; Mn? C = 184.4(6) pm; C? O = 113.3(7) pm. A comparison of the Sn2Mn2 ring with similar metal rings has been given.  相似文献   

13.
Ca9Cl8(BC2)2 was obtained by solid state reaction of a mixture of CaCl2, Ca, B and C. The structure was solved by single crystal X-ray structure determination. Ca9Cl8(BC2)2 crystallizes in the orthorhombic space group Cmcm (No. 63, a = 1162.91(8) pm, b = 1341.59(10) pm and c = 1208.62(9) pm, Z = 4). The most striking element of the title compound is the bent BC25– unit that is surrounded by a bicapped trigonal prismatic arrangement of calcium ions.  相似文献   

14.
The Crystal Structures of ErSeI and NaErSe2 It is reported about attempts to synthesize lanthanoide selenidehalides of the formula LnSeX (X ? Cl, Br, I) exemplary for Ln ? Er. The relative stabilities of these compounds are discussed. X-ray crystal structure analysis revealed for the compounds ErSeBr and ErSeI the FeOCl-structure type (space group Pmmn, Z = 2, a = 406.3(5) pm, b = 559.2(6) pm, and c = 795(1) pm, and a = 418.26(6) pm, b = 558.4(1) pm, and c = 889.0(2) pm, respectively). A corresponding chloride was not found within the scope of this investigation. From the educts Er2Se3 and ErCl3 in the presence of NaCl as flux in Nb-ampoules the compound NaErSe2 was formed instead which crystallizes in an α-NaFeO2-type structure (space group R3 m, Z = 3, a = 408.41(2) pm and c = 2067.4(2) pm).  相似文献   

15.
On Fluorides of Univalent and Divalent Mercury For the first time Rb2HgF4 and Cs2HgF4, both colourless, have been obtained. From single crystal investigations they crystallize tetragonal in the K2NiF4-type of structure, space group I4/mrnm-D4h17 (No. 139) with a = 455.6 pm, c = 1375.7 pm, Z = 2 for Rb2HgF4 and a = 462.5 pm, c = 1451.8 pm, Z = 2 for Cs2HgF4. The determination of the crystal structure of Hg2F2 confirmed the unit cell [1] with a = 367.00(4) pm, c = 1090.1(2) pm, Z = 2 space group I4/mrnm-D4h17 (No. 139).  相似文献   

16.
Hydroxo Compounds. 12. Crystal Structure and Constitution of Sodium Trihydroxozincate Na[Zn(OH)3] 1 The crystal structure of the very sensitive sodium trihydroxozincate Na[Zn(OH)3] 1 has been determined at 190 K. Contrary to the observations of trigonal planar [Zn(OH)3]? anions at 298 K, the structure of 1 at lower temperatures is characterized by 1-dimensional chains [Zn(OH)2(OH)2/2]? with the much more plausible (distorted) tetrahedral coordination of the Zn atoms (P42bc? C4v 6; Nr. 106; a = 1083.9 pm; c = 530.8 pm; Z = 8; Zn? O = 194.3–200.5 pm). The H positions were determined unambigeously from the X-ray data in complete agreement with calculations of potential profiles. There are pronounced hydrogen bond distances present. The Na atoms are coordinated by (5+1) oxygen atoms (Na? O = 234.8–248.8 pm and 282.7 pm). The noncentric coordination of the atoms as well as the strong anisotropic and anharmonic temperature tensors indicate a second order phase transition between 190 K and 298 K.  相似文献   

17.
1,3,5,7-Tetraphospha-2,4,6,8,9-decamethyl-2,4,6,8,9-pentasila-bicyclo (3.3.1)-nonan. Structure and Reactions The structure of the title compound 1 (white quad-shaped crystals, mp. 193°C) obtained by reaction of Li2PH with Me2SiCl2, is identified by 31PNMR and mass spectra as well as X-ray structure analysis. Compound 1 crystallizes in the monoclinic space group C2/c (No. 15) with a = 1563.6(28) pm, b = 1166.7(9) pm, c = 2556.0(27) pm, = 87.07(12)° and Z = 8 formula units in the elementary cell. The molecule has approximately mm (C2v) symmetry. The boat-boat conformation characterizes 1 as direct precursor of the dodecamethyl-hexasila-tetraphospha-adamantane. The bond lengths and bond angles are normal with d?(P? Si) = 224.5 pm and d?(Si? Me) = 186.0 pm. The H bonded to P are directed exocyclic. 1 reacts with (CO)4CrNBD (NBD = Norbornadiene) (bidentate ligand) to (SiMe2)5P2(PH)2Cr(CO)4 2 while closing the structure of compound 1 to the adamantane structure via the inserted Cr(CO)4.  相似文献   

18.
Cs5Sb8 and β‐CsSb: Two New Binary Zintl Phases The anion in the crystal structure of the new Zintl phase Cs5Sb8 synthesized from the elements (monoclinic, space group P21/c, a = 724.4(2) pm, b = 1135.2(3) pm, c = 2750.9(8) pm, β = 96.663(5)°, Z = 4) consists of two and three bonded Sb atoms, which are connected to form puckered nets with 5 and 28 membered rings. β‐CsSb (monoclinic, space group P21/c, a = 1519.4(3) pm, b = 734.0(2) pm, c = 1432.2(2) pm, β = 113.661(3)°, Z = 4) crystallizes with a superstructure of the LiAs structure type. As in the α phase (NaP type), twobonded Sb atoms form neary ideal 41 screx chains. In contrast to the α phase the helices have opposite chirality.  相似文献   

19.
Crystal Structure of the Compounds BaCaGaF7 and BaCaCrF7 The isostructural fluorides BaCaGaF7 and BaCaCrF7 (values in parentheses) crystallize monoclinically in space group P2/n, Z = 4: a = 539.0 (539.8), b = 541.0 (542.2), c = 1897.8 (1900.6) pm, β = 92.33 (92.10)°. Complete X-ray single crystal structure determinations showed, that the compounds are built up from triple layers [CaF8/2 · MF3]2?, which consist of a central sheet of edge-sharing CaF8/22? polyhedra (distorted square antiprisms) with MIIIF6octahedra condensed on it at both sides and which are held together by 12-coordinated barium ions. The resulting average distances are: Ga? F = 187.8 (Cr? F = 189.4) pm, Ca ? F = 236.2 (236.2) pm, Ba? F = 289.4 (289.4) pm. Some relations to the structures of other fluorides are discussed.  相似文献   

20.
The binary silicides Eu5Si3 and Yb3Si5 were prepared from the elements in sealed tantalum tubes and their crystal structures were determined from single crystal X-ray data: I4/mcm, a = 791.88(7) pm, c = 1532.2(2) pm, Z = 4, wR2 = 0.0545, 600 F2 values, 16 variables for Eu5Si3 (Cr5B3-type) and P62m, a = 650.8(2) pm, c = 409.2(1) pm, Z = 1, wR2 = 0.0427, 375 F2 values, 12 variables for Yb3Si5 (Th3Pd5 type). The new silicide Eu5Si3 contains isolated silicon atoms and silicon pairs with a Si–Si distance of 242.4 pm. This silicide may be described as a Zintl phase with the formula [5 Eu2+]10+[Si]4–[Si2]6–. The silicon atoms in Yb3Si5 form a two-dimensional planar network with two-connected and three-connected silicon atoms. According to the Zintl-Klemm concept the formula of homogeneous mixed-valent Yb3Si5 may to a first approximation be written as [3 Yb]8+[2 Si]2–[3 Si2–]6–. Magnetic susceptibility investigations of Eu5Si3 show Curie-Weiss behaviour above 100 K with a magnetic moment of 7.85(5) μB which is close to the free ion value of 7.94 μB for Eu2+. Chemical bonding in Eu5Si3 and Yb3Si5 was investigated by semi-empirical band structure calculations using an extended Hückel hamiltonian. The strongest bonding interactions are found for the Si–Si contacts followed by Eu–Si and Yb–Si, respectively. The main bonding characteristics in Eu5Si3 are antibonding Si12-π* and bonding Eu–Si1 states at the Fermi level. The same holds true for the silicon polyanion in Yb3Si5.  相似文献   

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