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1.
Rubidium Hexaamidolanthanate and -neodymate, Rb3[La(NH2)6] and Rb3[Nd(NH2)6]; Compounds. Structurally Related to K3[Cr(OH)6] and K4CdCl6 Colourless Rb3[La(NH2)6] (a = 12.298(4) Å, c = 13.759(2) Å, N = 6, R3 c) and pale blue Rb3[Nd(NH2)6] (a = 12.199(6) Å, c = 13.626(4) Å, N = 6, R32) have been prepared by the reaction of the corresponding metals (Rb: La resp. Nd = 3:1) with NH3(P(NH3) = 4–4.5 kbar) at 300°C. Single crystal x-ray methods gave their structures. It is shown by space group relations that these compounds are structurally related to one another and to further ternary amides as well as to K3[Cr(OH)6] and K4CdCl6.  相似文献   

2.
Three Novel Selenoborato- closo -dodecaborates: Syntheses and Crystal Structures of Rb8[B12(BSe3)6], Rb4Hg2[B12(BSe3)6], and Cs4Hg2[B12(BSe3)6] The three selenoborates Rb8[B12(BSe3)6] (P1, a = 10.512(5) Å, b = 10.450(3) Å, c = 10.946(4) Å, α = 104.53(3)°, β = 91.16(3)°, γ = 109.11(3)°, Z = 1), Cs4Hg2[B12(BSe3)6] (P1, a = 9.860(2) Å, b = 10.740(2) Å, c = 11.078(2) Å, α = 99.94(3)°, β = 90.81(3)°, γ = 115.97(3)°, Z = 1), and Rb4Hg2[B12(BSe3)6] (P1, a = 9.593(2) Å, b = 10.458(2) Å, c = 11.131(2) Å, α = 99.25(3)°, β = 91.16(3)°, γ = 116.30(3)°, Z = 1) were prepared from the metal selenides, amorphous boron and selenium by solid state reactions at 700 °C. These new chalcogenoborates contain B12 icosahedra completely saturated with six trigonal-planar BSe3 entities functioning as bidentate ligands to form a persubstituted closo-dodecaborate anion. The two isotypic compounds Rb4Hg2[B12(BSe3)6] and Cs4Hg2[B12(BSe3)6] are the first selenoborate structures containing a transition metal which are characterized by single crystal diffraction.  相似文献   

3.
A solution of sodium in liquid ammonia reacts with Sb2S3 to form large colorless crystals of the composition Na3SbS3⋅10 NH3. The trigonal‐pyramidal SbS33− anion is ion‐paired with three Na+ counter ions, the coordination spheres of which are completed by eight ammine ligands. The resulting neutral [Na(NH3)3]2[Na(NH3)2]SbS3 molecules crystallize together with two ammonia molecules of solvation in the space group P21/c (a=9.828(2), b=6.0702(4), c=33.4377(6) Å, β=91.362(7)°, V=1994.2(5) Å3, Z=4).  相似文献   

4.
Rubidium Decaamidodichromate(III), Rb4Cr2(NH2)10 – Synthesis and Crystal Structure The reaction of chromium(III) with rubidium amide in a molar ratio of Cr(NH2)3/RbNH2 = 1 : 1.75 at 140 °C and p(NH3) = 3 kbar in a high-pressure autoclave results after 90 days in dark violet crystals of Rb4Cr2(NH2)10. Structure determination was done by single crystal X-ray methods:Pna21 (No. 33), Z = 4, a = 12.244(3) Å, b = 6.727(1) Å, c = 19.775(5) Å, N(F2o > 3σ(F2o)) = 1046, N(Var.) = 94, R/Rw = 0,051/0,059&#TAB;The structure of Rb4Cr2(NH2)10 contains isolated, face-sharing N-octahedra around two Cr3+-ions giving [Cr(NH2)3(NH2)3/2]23–. These are arranged to oneanother following the motif of a hexagonal closest packing. They are connected via Rb+- and one further amide ion not bound to Cr3+. The compound is characterized by thermoanalytical and IR-/Raman-spectroscopic measurements.  相似文献   

5.
We present the low‐temperature synthesis of potassium hexaamido zirconate(IV) from the transition metal tetrafluoride and thealkali metal dissolved in liquid ammonia at –40 °C. Potassium hexaamido zirconate(IV) K2[Zr(NH2)6] is the first ternary amide reported for elements of group 4 of the periodic table It crystallizes with a novel structure type in the trigonal space group R$\bar{3}$ c with a = 6.5422(2) Å, c = 32.824(2) Å, V = 1216.66(9) Å3, Z = 6 and c/a = 5.017. The structure can be derived from the K2PtCl6 type. The compound contains discrete D3‐symmetric [Zr(NH2)6]2– anions which differ significantly from octahedral shape. Quantum chemical calculations show the distortion to arise from a splitting of degenerate d‐orbitals on the zirconium atom leading to a significant gain in energy.  相似文献   

6.
Preparation, properties, and crystal structure of Na3[Yb(NH2)6] Na3[Yb(NH2)6] was prepared by the reaction of Na and Yb in the atomic ration 3:1 with ammonia at 150°C and 200 atm as a light grey microcrystalline powder. Colourless single crystals were obtained at 180°C and ~6000 atm. It decomposes rapidly at temperature above 140°C. At 250°C NaNH2 nd a nitride phase results which crystallizes in the Nacl lattice type with a = 4.86 Å. Na3[Yb(NH2)6] crystallizes orthorhombically with the lattice spacings a = 6.492 Å, b = 12.24 Å, and c = 21.33 Å with 8 formula units per unit cell. The space group is D–Pbca (No.61). The amide ions have a distorted close-packed arrangement with the layer sequence ABAC in the direction [010]. Ytterbium occupies on sixth, sodium one half of the octahedral interstices.  相似文献   

7.
Transparent yellow crystals of Ba4[WN4]Cl2 were grown at 850°C by the reaction of Ba(NH2)2 with W in a KCl melt under flowing nitrogen. The compound crystallizes monoclinic in P21/m and Z = 2 with the cell parameters a = 8.447(4) Å, b = 6.143(2) Å, c = 10.727(6) Å and β = 99.04(4)°. The crystal structure contains isolated anions [WN4]6? and Cl?. It is the first nitridotungstate(VI) chloride reported so far.  相似文献   

8.
Tetrarubidiumnonagermanid(4–)-ethylendiamin, Rb4[Ge9][en] Orange-farbene Kristalle von Rb4[Ge9][en] erhält man nach der Austauschreaktion einer Lösung von ,NaGe2.25‘ (precursor) in Ethylendiamin (en) mit festem RbI bei 360 K und nachfolgender langsamer Abkühlung. Die Verbindung ist äußerst empfindlich gegen Oxidation und Hydrolyse. Der thermische Abbau im dynamischen Vakuum beginnt mit der vollständigen Abgabe von en bei 350 K. Es folgt die Sublimation von Rubidium in vier weiteren Stufen (Rb8Ge25, Rb8Ge44, RbxGe136 mit x È 16, Ge). Das Ramanspektrum zeigt die charakteristischen Banden des Anions [Ge9]4– bei 151, 163, 185 und 222 cm–1. Rb4[Ge9][en] kristallisiert in einem neuen Strukturtyp (Raumgruppe P21/m; a = 15.353 Å, b = 16.434 Å, c = 15.539 Å, β = 113.75°; Z = 6; Pearsonsymbol mP198-40), der als hierarchische Variante der Strukturen von Al4YbMo2 und CrB4 (hierarchische Basistypen, „initiators”︁) beschrieben werden kann, indem Atome partiell durch Aggregate ersetzt werden: B4[□][Cr] ≙ Al4[Yb][Mo]2 ≙ Rb4[Ge9][en]1–2. Drei kristallographisch unabhängige [Ge9]4–-Cluster sind in ein vierbindiges 465-Netz aus Rb-Atomen eingebettet, ein Netzwerk kondensierter Tetraasterane. Die Cluster sind verzerrte überkappte tetragonale Antiprismen mit D1(Ge–Ge) = 2.57 Å (16 Ç ) und D2(Ge–Ge) = 2.84 Å (4 Ç ). Die Atome der Cluster mit D1 und D2 liegen auf der Oberfläche eines Rotationsellipsoids (a = b = 2.136 Å, c = 2.431 Å). Die en-Moleküle befinden sich in offenen Kanälen entlang [1¯ 0 1]. Die Koordinationen [Ge9]Rb12/4 und Rb [Ge9]4/12 en2/8 zeigen, daß beim ersten Schritt der Solvatisierung Kationen und Clusteranionen nicht voneinander getrennt werden.  相似文献   

9.
Preparation and Properties of the Alkali Hexaiodatogermanates(IV), M2[Ge(IO3)6] Germanium dioxide aquate and alkali nitrates react with iodic acid to yield alkali hexaiodatogermanates(IV), M2[Ge(IO3)6], (M = NH4, K, Rb, Cs). The unit-cell dimensions of the trigonal cell are for K2[Ge(JO3)6] a0 = 11.16 Å, c0 = 11.34 Å, z = 3. The compounds M[MIV(IO3)6] (MI = NH4, K, Rb, Cs, MIV = Ge, Sn, Pb, Ti, Zr, Mn) are isomorphous1).  相似文献   

10.
The crystalline structure of a new compound Rh(III) of (NH4)2[Rh(NO2)3(NH3)(μ-OH)]2 composition has been determined. The crystallographic characteristics are H16N10O14Rh2: a = 6.3963(2) Å, b = 9.3701(4) Å, c = 13.6646(5) Å, β = 102.266(1)°, V = 800.28(5) Å3, Z = 2, d calc = 2.432 g/cm3. The distance Rh...Rh in the dimer is 3.200 Å. Original Russian Text Copyright ? 2006 by S. P. Khranenko, I. A. Baidina, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No. 2, pp. 380–384, March–April, 2006.  相似文献   

11.
Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of [Co(NH3)6][Os(SCN)6] From the mixture of the linkage isomers [Os(NCS)n(SCN)6–n]3–, n = 0–2, pure [Os(SCN)6]3– has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of [Co(NH3)6][Os(SCN)6] (trigonal, space group R 3, a = 12.368(2), c = 11.830(2) Å, Z = 3) reveals that the thiocyanate ligands are exclusively S‐coordinated with the Os–S distance of 2.388 Å and the Os–S–C angle of 108.8°. The IR and Raman spectra of (n‐Bu4N)3[Os(SCN)6] are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constant fd(OsS) is 1.42 mdyn/Å.  相似文献   

12.
The crystal structures of Co3[Co(CN)6]2, 12 H2O (a, = 10.210 ± 0.005 Å) and Cd3[Co(CN)6]2, 12 H2O (a = 10.590 ± 0.005 Å) have been determined by X-ray powder methods. According to the measured density the unit cell contains 1 1/3 formula units with 4 Co2+ (Cd2+) in 4a, 2 2/3 Co3+ in 4b, 16 C and 16 N in 24e, 8 H2OI near 24e, (96k) and 8 H2OII near 8 c (192 l). Structure factor calculations based on the space group Oh5 - F m 3 m lead to the following final values of the reliability index R: 0.038 (Co3[Co(CN)6]2, 12 H2O) and 0.037 (Cd3[Co(CN)6]2, 12 H2O). The interatomic distances for the cobaltous compound (in parentheses for the cadmium compound) are: Co3+-C: 1.88 Å (1.89); C-N: 1.15 Å (1.17); Co2+-N: 2.08 Å (2.24); Co2+-OI: 2.10 Å (2.27); shortest OI-H-OII-bonds: 2.89 Å (2.82). Co3+ is octahedrally coordinated by six carbon atoms, the divalent metal ion by four nitrogen atoms and two water molecules. The two different metal ions are connected by M2+-N-C-Co3-bonds to a threedimensional network. The infrared and electronic spectra are shown to be in agreement with the results of the structure analyses of these compounds. The observed positions of the OH-stretching vibrations lead to a hydrogenbond-length of 2.8–2.95 Å.  相似文献   

13.
Single crystals of three rubidium uranyl selenates, Rb2[(UO2)(SeO4)2(H2O)](H2O) ( 1 ), Rb2[(UO2)2(SeO4)3(H2O)2](H2O)4 ( 2 ), and Rb4[(UO2)3(SeO4)5(H2O)] ( 3 ), have been prepared by evaporation from aqueous solutions made out of mixtures of uranyl nitrate, selenic acid and Rb2CO3. The structures of all compounds have been solved by direct methods on the basis of X‐ray diffraction data sets. The crystallographic data are as follows: ( 1 ): orthorhombic, Pna21, a = 13.677(2), b = 11.8707(13), c = 7.6397(9) Å, V = 1240.4(3) Å3, R1 = 0.045 for 2396 independent observed reflections; ( 2 ): triclinic, P1¯, a = 8.4261(12), b = 11.8636(15), c = 13.3279(18) Å, α = 102.612(10), β = 107.250(10), γ = 102.510(10)°, V = 1183.7(3) Å3, R1 = 0.067 for 4762 independent observed reflections; ( 3 ): orthorhombic, Pbnm, a = 11.3761(14), b = 15.069(2), c = 19.2089(17) Å, V = 3292.9(7) Å3, R1 = 0.075 for 3808 independent observed reflections. The structures of the phases 1 , 2 , and 3 are based upon uranyl selenate hydrate sheets composed from corner‐sharing pentagonal [UO7]8— bipyramids and [SeO4]2— tetrahedra. In the crystal structure of 1 , the sheets have composition [(UO2)(SeO4)2(H2O)]2— and run parallel to (001). The interlayer contains Rb+ cations and additional H2O molecules. In structure of 2 , the [(UO2)2(SeO4)3(H2O)2]2— sheets are oriented parallel to (101). Highly disordered Rb+ cations and H2O molecules are located between the sheets. The structure of 3 is based upon [(UO2)3(SeO4)5(H2O)]4— sheets stacked parallel to (010) and contains Rb+ cations in the interlayers. The topologies of the uranyl oxoselenate sheets observed in the structures of 1 , 2 , and 3 are related to the same simple and highly‐symmetric graph consisting of 3‐connected white and 6‐connected black vertices.  相似文献   

14.
Ammonolysis Reaction of (NH4)2GeF6. Synthesis and Structure of NH4[Ge(NH3)F5] (NH4)2GeF6 reacts with ammonia to yield NH4[Ge(NH3)F5] at 280°C. The reaction path was elucidated by in situ time and temperature resolved X-ray powder diffraction. NH4[Ge(NH3)F5] crystallizes isostructurally to NH4[Si(NH3)F5] in the tetragonal space group P4/n (No. 85) with lattice constants a = 619.41(1) pm and c = 724.70(1) pm. The germanium atom is coordinated by five fluorine atoms and the nitrogen atom of the ammonia molecule. The ammonium cation is located on the Wyckoff position (2 a) in P4/n. The crystal structure is stabilized by extensive hydrogen bonding.  相似文献   

15.
The monoammoniate of lithium amidoborane, Li(NH3)NH2BH3, was synthesized by treatment of LiNH2BH3 with ammonia at room temperature. This compound exists in the amorphous state at room temperature, but at ?20 °C crystallizes in the orthorhombic space group Pbca with lattice parameters of a=9.711(4), b=8.7027(5), c=7.1999(1) Å, and V=608.51 Å3. The thermal decomposition behavior of this compound under argon and under ammonia was investigated. Through a series of experiments we have demonstrated that Li(NH3)NH2BH3 is able to absorb/desorb ammonia reversibly at room temperature. In the temperature range of 40–70 °C, this compound showed favorable dehydrogenation characteristics. Specifically, under ammonia this material was able to release 3.0 equiv hydrogen (11.18 wt %) rapidly at 60 °C, which represents a significant advantage over LiNH2BH3. It has been found that the formation of the coordination bond between ammonia and Li+ in LiNH2BH3 plays a crucial role in promoting the combination of hydridic B? H bonds and protic N? H bonds, leading to dehydrogenation at low temperature.  相似文献   

16.
A one‐dimensional aluminum phosphate, [NH3(CH2)2NH2(CH2)3NH3]3+ [Al(PO4)2]3—, has been synthesized hydrothermally in the presence of N‐(2‐Aminoethyl‐)1, 3‐diaminopropane (AEDAP) and its structure determined by single crystal X‐ray diffraction. Crystal data: space group = Pbca (no. 61), a = 16.850(2), b = 8.832(1), c = 17.688(4)Å, V = 2632.4(2)Å3, Z = 8, R1 = 0.0389 [5663 observed reflections with I > 2σ(I)]. The structure consists of anionic [Al(PO4)2]3— chains built up from AlO4 and PO4 tetrahedra, in which all the AlO4 vertices are shared and each PO4 tetrahedron possesses two terminal P=O linkages. The cations, which balances the negative charge of the chains, are located in between the chains and interact with the oxygen atoms through strong N—H···O hydrogen bonds. Additional characterization of the compound by powder XRD and MAS‐NMR has also been performed and described.  相似文献   

17.
New Heteropolyanions of the M2X2W20 Structure Type with Antimony(III) as a Heteroatom The syntheses of two new heteropolyanions of the M2X2W20 structure type are presented. They are characterized by X‐ray structure analysis and vibrational spectra. Na6(NH4)4[Zn2(H2O)6(WO2)2(SbW9O33)2]·36H2O (1) is monoclinic (P21/n) with a = 12.873(3)Å, b = 25.303(4)Å, c = 15.975(4)Å and β = 91.99(3)°. Na10[Mn2(H2O)6(WO2)2(SbW9O33)2]·40H2O (2) also crystallizes in the space group P21/n with a = 12.892(3)Å, b = 25.219(5)Å, c = 16.166(3)Å and β = 94.41(3)°. Both polyanions are isostructural to anions of this structure type containing other heteroatoms. They are built up by two β‐B‐SbW9 fragments, which are derived from defect structures of the Keggin anion. These subÍunits are connected by two formal WO2 groups with further stabilization by addition of two M(H2O)3 groups (M = ZnII, MnII, FeIII, CoII) leading to the M2X2W20‐type heteropolytungstates.  相似文献   

18.
A rhenium cluster complex [Ni(NH3)6]2.5·NH4[Re12CS17(CN)6]·8.5H2O is obtained and structurally described. The compound crystallizes in the triclinic space group P-1 with the unit cell parameters: a = 11.0856(13) Å, b = 15.242(2) Å, c = 21.232(3) Å, α = 90.158(4)°, β = 97.439(4)°, γ = 90.051(4)°, V = 3557.3(8) Å3, Z = 2, d calc = 3.287 g/cm3. The crystal structure represents a packing of [Ni(NH3)6]2+ and NH4 + cations, [Re12CS17(CN)6]6? cluster anions, and crystallization water molecules bound by a system of hydrogen bonds.  相似文献   

19.
The compound [Co(En)3]2[Hg2(H2O)Cl6]Cl4 (I, En is ethylenediamine) has been synthesized and studied by X-ray diffraction. The crystals of I (a = 21.8745(14) Å, b = 10.6008(6) Å, c=15.4465(12) Å, space group Pna21) consist of tris(ethylenediamine)cobalt(III) complexes (the unit cell contains two [Co(En)3]3+ cations of opposite chirality). [Hg2(H2O)Cl6]2? anions, and isolated chloride ions. The complex anion consists of the tetrahedral [HgCl4]2? group (Hg-Cl, 2.44–2.56 Å) and the hydrated molecule [Hg(H2O)Cl2] (Hg-Cl, 2.301 and 2.308 Å; Hg-O, 2.788 Å) combined by weak Hg-Cl interactions (2.915 and 3.220 Å).  相似文献   

20.
Ammonium hexamolybdobismuthate(III) of composition (NH4)3[BiMo6O18(OH)6] · 7H2O (I) was synthesized and studied by mass spectrometry, X-ray diffraction, IR spectroscopy, and thermogravimetry. The compound is monoclinic: a = 10.438 Å, b = 7.909 Å, c = 18.127 Å, β = 96.59°, V = 1486.76 Å3, ρcalc = 3.32 g/cm3, Z = 2.  相似文献   

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