Protonenlagen bei Kaliumtetraamidozinkat,K2Zn(NH2)4

Positions of the Protons in Potassium Tetraamidozincate, K₂Zn(NH₂)₄ X-ray single crystal data for K₂Zn(NH₂)₄ allowed the determination of the so far unknown positions of the protons: P1 , Z = 2, a = 6.730(1) Å, b = 7.438(1) Å, c = 8.019(2) Å, α = 72.03(2)°, β = 84.45(2)°, γ = 63.82(1)°, Z(F₀) with (F₀)² ≥ 3σ(F₀)² = 2166, Z(parameters) = 96, R/R_W = 0.032/0.039. In the structure of K₂Zn(NH₂)₂ the amide ions are nearly hexagonal close packed. One layer of octahedral holes parallel to (010) is fully occupied by potassium atoms and zinc is in an ordered way in a quarter of the tetrahedral holes of the next layer. The orientation of the protons of the amide ions is characteristic for this type of structure (filled up CdI₂ type).     

Crystal structure of barium (cyclohexane-1,2-diaminetetraacetato)cobaltate(III) nonahydrate Ba[Co(Cdta)]2 · 9H2O

The crystal structure of Ba[Co(Cdta)]₂ · 9H₂O has been determined by X-ray diffraction. The crystals are monoclinic, a = 15.9415(10) Å, b = 7.8449(6) Å, c = 32.230(2) Å, β = 100.387(8)°, Z = 4, space group C2/c)). The cyclohexane-1,2-diaminetetraacetate ion forms the octahedral [Co(Cdta)]^? complex through two donor nitrogen atoms and four oxygen atoms and is also connected to two barium atoms through oxygens. The Ba atoms are on a twofold axis. Its nearest environment comprises five O atoms of water molecules, one also being located on a twofold axis, and four O atoms of the four neighboring complex ions. This gives infinite layers parallel to the ab plane. All water molecules form hydrogen bonds within one layer.     

Darstellung und KristallStruktur des Rubidiumcalciumamids,RbCa(NH2)3

Preparation and Crystal Structure of the Rubidium Calcium Amide, RbCa(NH₂)₃ In the system Rb/Ca/NH₃ a ternary amide, RbCa(NH₂)₃, has been prepared by the reaction of the metals with supercritical NH₃ at T = 573 K and P = 5 000 bar. The x-ray investigation of single crystals of the compound led to the structure: a = 7.080 ± 0.006 Å, b = 11.95 ± 0.01 Å, c = 6.540 ± 0.006 Å, and β = 108.5 ± 0.1°; space group: C2/c ? No. 15, Z = 4. The atomic arrangement shows onedimensional infinite face-sharing anion-octahedra, which are occupied by calcium. The rubidium connects the octahedra-chains. The orientation of the protons corresponds to the stronger electrostatic influence of the calcium – compared with that of the rubidium ions.     

Structure Determination of a Low Temperature Phase of Calcium and Strontium Amide by means of Neutron Powder Diffraction on Ca(ND2)2 and Sr(ND2)2

Calcium and Strontium amide are ionic compounds crystallising in a tetragonally distorted anatase structure-type at ambient temperatures. The amide ions (NH₂^–/ND₂^–) resemble water molecules in structure and in charge distribution. By means of temperature dependent neutron diffraction investigations weak super-structure reflections were observed at temperatures below 90 K (Ca(ND₂)₂) and 60 K (Sr(ND₂)₂), respectively, indicating the existence of a so far unknown low-temperature (LT) phase. Using high resolution neutron powder diffraction at temperatures below 10 K the structure was determined for both compounds. The LT-phases are isotypic and crystallise monoclinic in the space group P2₁/c with four formula units within the unit cell: Ca(ND₂)₂ at 10 K a = 7.257(2) Å, b = 7.2434(2) Å, c = 6.300(1) Å, β = 124.73(1)° Sr(ND₂)₂ at 5 K a = 7.6950(1) Å, b = 7.68374(9) Å, c = 6.6324(3) Å, β = 124.917(2)°. Their structure is closely related to the tetragonal HT-phase, but an ordering of the amide ions occurs due to freezing of a lattice mode which is dominated by the librational motion of the amide ions in the {1 0 0} planes of the HT-phase.     

Wasserstoffbrückenbindungen in den Monoammoniakaten von Kalium‐ und Caesiumamid

Hydrogen Bonds in the Monoammoniates of Potassium and Cesium Amide X‐ray structure determination was carried out on the monoammoniates of potassium and cesium amide. Crystals of KNH₂ · NH₃ were grown from liquid NH₃ at 50 °C > T > 20 °C. They crystallize in the cold part of a pressure resistant glass apparatus. Single crystals of CsNH₂ · NH₃ were obtained by zone‐melting at —30 °C in x‐ray capillaries. The following data characterize the crystal chemistry of the compounds: KNH₂ · NH₃ Cmc2₁, Z = 4 21 °C a = 3, 938(1) Å, b = 10, 983(3) Å, c = 5, 847(1) Å CsNH₂ · NH₃ Pnma, Z = 4 30 °C a = 7, 103(1) Å, b = 5, 390(1) Å, c = 10, 106(2) Å For CsNH₂ · NH₃ all hydrogen atom positions were successfully refined. The structure of both ammoniates may be described by a distorted hexagonal close packed arrangement of cations with the NH₃ molecules in the octahedral and the NH₂^— anions in the trigonal bipyramidal interstices. The three H atoms of the NH₃ molecules are involved in hydrogen bridge bonds to two amide ions with d(N(NH₃)···N(NH₂^—)) = 2.60Å for the K and 3.19Å for the Cs compound and to a further NH₃ molecule with d(N(NH₃)···N(NH₃)) = 2.98Å for the K and 3.56Å for the Cs compound. Structural relationship of the ammoniates to the monohydrates of KOH and RbOH is discussed.     

Lithiumaluminiumamid,LiAl(NH2)4, Darstellung,röntgenographische Untersuchung,Infrarotspektrum und thermische Zersetzung

Lithium Aluminium Amide, LiAl(NH₂)₄-Preparation, X-Ray Investigation, I.R.Spectrum, and Thermal Decomposition The reaction of lithium and aluminium with liquid ammonia gives LiAl(NH₂)₄ within some days at temperatures from 80–100°C. Crystals for an X-ray structure determination must be grown very slowly from liquid NH₃ starting with thoroughly pulverized amide. The structure analysis was successful including the determination of the positions of the hydrogen atoms of the amide ions. Space group: P2₁/n; lattice constants: a = 9.478(1) Å, b = 7.351(1) Å, c = 7.398(1) Å, β = 90.26(1)°; Z = 4, R-values (unweighted, weighted with w = 1): 0.042/0.046. The atomic arrangement of LiAl(NH₂)₄ can formally be described as a new variant of the GaPS₄-type structure. The compound is characterized too by its i.r. spectrum. The thermal degradation of LiAl(NH₂)₄ gives at 180°C amorphous Al₂(NH)₃ and crystalline LiNH₂; at 220°C results already very fine AlN. Above 400°C this AlN reacts with LiNH₂ or Li₂NH forming Li₃AlN₂.     

Neubestimmung von Struktur und Eigenschaften isotyper Natriumtetraamidometallate des Aluminiums und Galliums

Redetermination of Structure and Properties of the Isotypic Sodium Tetraamido Metallates of Aluminium and Gallium Crystals for x-ray structure determination of NaAl(NH₂)₄ and NaGa(NH₂)₄ were obtained by the reaction of the metals with ammonia in autoclaves at 100°C and P(NH₃) = 60 bar within 7 days. The compounds crystallize isotypic in the space group P2₁/c with Z = 4 NaAl(NH₂)₄ a = 7.328(2) Å, b = 6.047(2) Å, c = 13.151(3) Å, β = 94.04(1)° NaGa(NH₂)₄ a = 7.4087(8) Å, b = 6.0917(5) Å, c = 12.855(2) Å, β = 92.10(1)° The structures were refined inclusively all H-positions of the amide ions. The ternay amides are furthermore characterized by their IR spectra and their thermal behaviour.     

Röntgenographische und spektroskopische Untersuchungen an Ba2Ni(N3)6· 3H2O

Preparation and X-Ray Examination of Ba₂Ni(N₃)₆ · 3 H₂O Ba₂Ni(N₃)₆ · 3 H₂O has been prepared by the reaction of an aqueous solution of Ba(N₃)₂ with basic nickel azide. The crystals are green, the lattice constants are: a = 7.09 Å, b = 7.09 Å, c = 16.30 Å, α = 74.58°, β = 105.42°, γ = 97.10°, N = 2. Optical spectra point to an octahedral microsymmetry of the azide ions around nickel.     

Darstellung,Eigenschaften und Kristallstruktur von Na3[Yb(NH2)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.     

Die Kristallstruktur von Berylliumamid,Be(NH2)2

Inhaltsübersicht. Die röntgenographische Untersuchung von Einkristallen des Beryllium-amids ergab, daß die Verbindung tetragonal kristallisiert. a = 10.170 ± 0.005 Å. c = 16,137 ± 0,008 Å und c/a = 1,587, in der Raumgruppe I4₁/acd mit 32 Formeleinheiten in der Elementarzelle. Es wurden die Lagen aller Atome einschließlich derer des Wasserstoffs bestimmt. Die Struktur des Be(NH₂)₂ leitet sich von einem stark verzerrten, kubisch dichten Anionenteilgitter ab. Die Kationen befinden sich derart in Tetraederlürken. daß jeweils 4 Be²⁺-Ionen ein regulärs Tetraeder mit den kürzesten Be — Be-Abständen bilden. Dadurch entstehen Einheiten, die sich als Be₄(NH₂)₆(NH₂)_4/2 wiedergeben lassen, wobei die äußeren 4 Amidionen als Brückenanionen für die dreidimensionale Verknüpfung wirken. Die Ausrichtung der Amidionen wird beschrieben und mit den Ergebnissen früherer Untersuchungen an venvandten Metallamiden verglichen. Crystal Structure of Beryllium Amide, Be(NH₂)₂ Abstract. The x-ray investigation of single crystals of beryllium amide led to the following results. The compound crystallizes tetragonally a = 10.170 ± 0.005 Å, c = 16.137 ± 0.008 Å, and c/a = 1.587. The space group is I4₁/acd. The lattice contains 32 formula units. The positions of all atoms including hydrogen were determined. The structure of Be(NH₂)₂ can be described by a strongly deformed cubic closepacking of anions. The cations occupy tetrahedral interstices so that 4 Be²⁺ ions form a regular tetrahedron with the shortest Be—Be distances. This causes units, which can be described by Be₄(NH₂)₆(NH₂)_4/2 Whereas the outer 4 amide ions serve as bridging anions to give a threedimensional arrangement. The orientation of the amide ions is given and compared with earlier results on similar metal amides.     

Darstellung und Kristallstruktur von K3La(NH2)6

Preparation and Crystal Structure of K₃La(NH₂)₆. Single crystals of K₃La(NH₂)₆ were obtained by the reaction of the metals (3 K + 1 La) during five days at 200°C and 4000 atm NH₃ pressure. The compound crystallizes monoclinic with a = 6.74, b = 11.67, c = 7.23 Å and β = 108.1°; the space group is C2/m (No. 12). The lattice contains 2 formula units. The amide ions are arranged in a strongly distorted cubic closepacking. All cations occupy edging anion-octahedra.     

Crystal structure and triboluminescence of the [Eu(TTA)2(NO3)(TPPO)2] complex

The crystal structure of [Eu(TTA)₂(NO₃)(TPPO)₂] (I) (TTA = thenoyltrifluoroacetone, TPPO = triphenylphosphine oxide) possessing intense triboluminescence was established by X-ray crystallography. The crystals are triclinic, noncentrocymmetrical: a = 11.047(3) Å, b = 11.794(3) Å, c = 12.537(3) Å; α = 102.635 (4)°, β = 102.088(4)°,γ = 117.765(3)°; space group P1, Z = 1. The central Eu(III) atom coordinates two oxygen atoms of two TPPO molecules at distances of 2.271 Å and 2.282 Å, two oxygen atoms of the nitrate group at distances of 2.478 Å and 2.481 Å, four oxygen atoms of two TTA ions at distances of 2.365 Å, 2.381 Å, and 2.363 Å, 2.371 Å (coordination number is 8). The coordination polyhedron of the Eu(III) atom is a distorted dodecahedron. Possible reasons for spectral differences in the Stark structure of photo-and triboluminescence of I are discussed.     

Synthese et structure cristalline de Ba1.14K0.72VS4

Single crystals of a new compound, Ba_1.14K_0.72VS₄ have been obtained from a flux of KCl at 950°C. This is the first quaternary sulfide in the BaKVS system and it is a diamagnetic insulator at room temperature. The compound has orthorhombic symmetry, Pna2₁, with unit cell dimensions a = 9.158(2)Å, b = 12.144(3)Å, c = 6.729(1)Å, Z = 4. Its structure was determined using heavy-atom methods and refined to an R value of 0.031 (wR = 0.022); 5654 intensities were measured, using AgKα radiation. The structure is related to K₂SO₄-β but is not centrosymmetric and the surroundings of the potassium atoms are different. Barium and potassium atoms are coordinated, respectively, to 9 and 11 sulfur atoms, forming polyhedrons which can be described as capped trigonal prisms. The vanadium cations, V⁵⁺, are tetrahedrally coordinated to sulfur atoms. The 0.72 potassium and 0.14 barium atoms share the same crystallographic site, explaining the relative high value of the thermal parameters.     

Synthese und Kristallstruktur von [Ba(18-Krone-6)(DMF)4][Cd(Se4)2]

Synthesis and Crystal Structure of [Ba(18-Crown-6)(DMF)₄][Cd(Se₄)₂] The title compound has been prepared by the reaction of a DMF-solution of lithium polyselenide with BaSe₂ and cadmium acetate in the presence of 18-crown-6, forming black crystals. The compound was characterized by IR spectroscopy and by an X-ray structure determination. Space group P2/a, Z = 4, 5392 observed unique reflections, R = 0.048. Lattice dimensions at ?90°C: a = 2021.9(12); b = 1019.8(6); c= 2270.8(14)pm, ß = 106.98(4)°. The structure consists of [Ba(18-crown-6)(DMF)₄]²⁺ ions, in which the barium ions are coordinated by the six oxygen atoms of the crown ether molecule and by four oxygen atoms of the DMF molecules, and of [Cd(Se₄)₂]^2? ions. The cadmium atoms are coordinated by two tetraselenide ions in a chelating fashion.     

Ba4[WN4]Cl2: The first nitridotungstate(VI) chloride

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.     

Kaliumamidotrioxogermanate(IV) – Wasserstoff-Brückenbindungen in K3GeO3NH2 und K3GeO3NH2 · KNH2

Potassium Amido Trioxo Germanates(IV) – Hydrogen Bridge Bonds in K₃GeO₃NH₂ and K₃GeO₃NH₂ · KNH₂ Colorless crystals of K₃GeO₃NH₂ and of K₃GeO₃NH₂ · KNH₂ were obtained by the reaction of KNH₂ with GeO₂ in supercritical ammonia at 450°C and p = 6 kbar in high-pressure autoclaves within 15 resp. 5 days. The crystal structures of both compounds were solved by X-ray single crystal methods. K₃GeO₃NH₂: P1 , a = 6.390(1) Å, b = 6.684(1) Å, c = 7.206(1) Å, α = 96.47(1)°, β = 101.66(1)°, γ = 91.66(1)°, Z = 2, R/R_w = 0.020/0.022, N(I) ≥ 2σ(I) = 3023, N(Var.) = 82 K₃GeO₃NH₂ · KNH₂: P2₁/c, a = 10.982(6) Å, b = 6.429(1) Å, c = 12.256(8) Å, β = 106.12(1)°, Z = 4, R/R_w = 0.022/0.029, N(F) ≥ 3σ(F) = 1745, N(Var.) = 107. In K₃GeO₃NH₂ tetrahedral ions GeO₃NH₂^3? are connected to chains by N? H …? O bridge bonds with 2.18 Å ≤ d(H …? O) ≤ 2.40 Å for d(N? H) ? 1.0 Å and by potassium ions while in K₃GeO₃NH₂ · KNH₂ bridge bonds between NH₂ groups of GeO₃NH₂^3? and NH₂^? ions as acceptors occur with 2.41 Å ≤ d((N? )H …? NH₂^?) ≤ 2.61 Å for d(N? H) ? 1.0 Å.     

Rubidium-decaamidodichromat(III), Rb4Cr2(NH2)10 – Synthese und Kristallstruktur

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(F²_o > 3σ(F²_o)) = 1046, N(Var.) = 94, R/R_w = 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]₂^3–. 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.     

A new dinuclear molybdenum(V)-sulfur complex containing citrate ligand: Synthesis and characterization of K2.5Na2NH4[Mo2O2S2(cit)2].5H2O

The complex, K_2.5Na₂NH₄[Mo₂O₂S₂(cit)₂]·5H₂O (1), was obtained by crystallization from a solution of (NH₄)₂MoS₄, potassium citrate (K₃cit) and hydroxyl sodium in methanol and water under an atmosphere of pure nitrogen at ambient temperature. The crystals are triclinic, space group P1¯, a = 7.376 (3)Å, b = 14.620 (2) Å, c = 14.661 (1) Å, α = 71.10 (1)°, β = 81.77 (1)°, γ = 78.27(2)°, R = 0.0584 for 2545 observed (I > 2σ (I)) reflections. Single crystal structure analysis reveals that citrate ligand coordinated to molybdenum atom through two carboxylato oxygens and one deprotonated hydroxyl oxygen together with two bridging sulfur atoms and a terminal oxygen atom completes distorted coordination octahedron around each molybdenum atom. Principal dimensions are Mo = O₁, 1.707 Å (av); Mo-S_b, 2.341 Å (av); Mo-O_(hydroxyl), 2.021 Å (av); Mo-O_{(α-carboxyl)}, 2.1290 Å (av) and Mo-O_{(β-carboxyl)}, 2.268(av) Å. IR spectrum is in agreement with the structure.     

Structural Investigations and Thermal Behavior of (NH4)[Cr(C2O4)2]·2H2O

Single crystals of ammonium chromium(III) dioxalate dihydrate (or ammonium diaquo bis(μ‐oxalato)chromate(III)) have been obtained from aqueous solution of oxalic acid and ammonium dichromate. A pale violet crystal of good optical quality was used for the structure determination at ?100(2) and 25(2) °C, respectively. The basic crystallographic data for the low temperature data set are as follows: monoclinic, space group C2/m, a = 6.597(2) Å, b = 7.301(2) Å, c = 9.983(3) Å, β = 92.32(2)°, V = 480.5(2) ų. The structure was solved by direct methods and refined (using anisotropic displacement parameters for all non‐hydrogen atoms) to a final residual of R1 = 0.032 for 503 independent observed reflections (I>2σ(I)). The compound is isotypic with the corresponding rubidium salt. The structure is built up from alternating layers parallel to (001) containing (NH₄)⁺ ions or Cr(C₂O₄)₂(H₂O)₂ octahedra, respectively. The corners of the octahedra consist of four O atoms from two oxalate groups and two additional water molecules. The ammonium cations (occupying Wyckoff‐site 2a) are disordered among two possible orientations. They provide linkage between different octahedral layers by hydrogen bridging. The water molecules in turn form hydrogen bridges with adjacent octahedra within the same layer. Further structural characterization included infrared spectroscopy. According to DTA/TG experiments the present compound shows several thermal processes in the range between room temperature and 900 °C.     

Die Kristallstruktur des 1 : 1-Adduktes zwischen Antimontrichlorid und Diphenylammoniumchlorid,SbCl3 · (C6H5)2NH2+Cl−

The Crystal Structure of the 1:1 Addition Compound between Antimony Trichloride and Diphenylammonium Chloride, SbCl₃ · (C₆H₅)₂NH₂⁺Cl^? The 1:1 addition compound between antimony trichloride and diphenylammoniumchloride SbCl₃ · (C₆H₅)₂NH₂⁺Cl^? crystallizes in the monoclinic space group P2₁/n with a = 5.668(8), b = 20.480(12), c = 14.448(17) Å, β = 110.4(1)° and Z = 4 formula units. Chains of SbCl₃ molecules and anion cation chains are bridged by Cl ions and form square tubes. The coordination of the Sb atoms by Cl atoms by Cl atoms and Cl ions is distorted octahedral. Mean distances are Sb? Cl = 2.37 Å for Sb? Cl (3×), 3.09 Å for Sb…Cl^? (2×) and 3.42 Å for Sb…Cl (1×). The Sb…Cl^? contacts and hydrogen bonds NH…Cl^? at 3.15 Å generate tetrahedral coordination of the Cl ions.