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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.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

15.
Single crystals of two new modifications of [P(C6H5)4]2[Cu2I4] were obtained by reaction of granulated copper with iodine and [P(C6H5)4]I in dry acetone under nitrogen atmosphere. They crystallise monoclinically, space group P21/n (No. 14), a = 11.550(6), b = 7.236(2), c = 27.232(13) Å, β = 98.13(3)°, V = 2253(2) Å3, and Z = 2 ([P(C6H5)4]2[Cu2I4]-C), and space group Cc (No. 9), a = 17.133(5), b = 15.941(5), c = 18.762 (6) Å, β = 114.02(1)°, V = 4681(3) Å3, and Z = 4 ([P(C6H5)4]2[Cu2I4]-D), respectively. In these compounds the [CuI2]? anions form dimers di-μ-iodo-diiodocuprate(I), which are either planar ( C ) or folded ( D ).  相似文献   

16.
The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO3)2]2− anions are grouped into centrosymmetric pairs and are surrounded by two K+ cations to give the overall layer composition {K2[Hg(SO3)2]2}2−. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO3)2]2− anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K+ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH4)2[Hg(SO3)2] and Na2[Hg(SO3)2]·H2O are discussed.  相似文献   

17.
Dissolution of solid AgNCO (silver isocyanate) in aqueous ammonia (25 %) and subsequent crystal growth at T = –9 °C furnished the new ammoniate (NH3)Ag(NCO) as colorless crystals [P21/c (no. 14); a = 4.1817(3) Å, b = 14.445(1) Å, c = 6.1988(5) Å, β = 102.0(4)°, V = 365,6(2) Å3; Z = 4]. In the molecular monammine complex, which is only stable at temperatures below T = 0 °C, silver is in a twofold, however, asymmetrical coordination by the isocyanate anion and ammonia. At the reaction conditions applied, AgNCO does not form an ionic diammine species (e.g. [Ag(NH3)2]+) as known from related silver salts. In this sense, the solvation chemistry of AgNCO exhibits a rarely observed feature.  相似文献   

18.
News on K2[MnF6], Rb2[MnF6], and Cs2[MnF6] Cs2[MnF6] (a = 8.972 Å) and Rb2[MnF6] (a = 8.531 Å) as well as this with K2[MnF6] (a = 8.221 Å and hexagonal a = 5.722, c = 9.331 Å) form mixed crystals of the K2PtCl6 type of structure. Calculations of the Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, lead contrary to former assumptions to distances Mn? F of about 1.86 Å (CN 6).  相似文献   

19.
Twisted Tetrahedra Chains 1[Li(NH2)4/2?] in the Structure of the Hexagonal Modification of Cesium Lithium Amide, CsLi(NH2)2 The ternary amides, CsLi(NH2)2 (dimorphous) and CsLi2(NH2)3, were prepared by reaction of the metals with ammonia in high pressure autoclaves. The structure of the hexagonal modification of CsLi(NH2)2 was established inclusive the hydrogen atom positions from single crystal x-ray data. The compound crystallizes in the space group P6222 with N = 3. The lattice parameters are a = 6.331(1) Å and c = 8.410(1) Å. Lithium ions occupy distorted nitrogen tetrahedra. These tetrahedra are connected by translocated edges along [001]. The cesium ions combine the equally oriented chains [Li(NH2)4/2?]. The amide ions are twisted out of the hexagonal aa-plane. If we assume sp3-hybridized valence electrons of the nitrogen atoms the bonding interaction between free electron pairs and lithium ions are thereby strenghtened.  相似文献   

20.
[Co(NH3)6] · H2[NiMo6O18(OH)6] · 6H2O (I) and [Co(NH3)6] · H2[ZnMo6O18(OH)6] · 6H2O (II) have been synthesized and studied by mass spectroscopy, thermogravimetry, and X-ray powder diffraction. The crystals of compounds I and II are monoclinic, Z = 1; for compound I: a = 16.10 Å, b = 5.58 Å, c = 12.22 Å, β = 117.86°, V = 1045.14 Å3, and ρcalcd = 2.26 g/cm3; for compound II: a = 16.12 Å, b = 5.52 Å, c = 12.12 Å, β = 117.90°, V = 1043.21 Å3, and ρcalcd = 2.21 g/cm3.  相似文献   

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