First characterization of the ammine-ammonium complex [(NH4(NH3)4)2(mu-NH3)2]2+ in the crystal structure of [NH4(NH3)4][B(C6H5)4].NH3 and the [NH4(NH3)4]+ complex in [NH4(NH3)4][Ca(NH3)7]As3S6.2NH3 and [NH4(NH3)4][Ba(NH3)8]As3S6.NH3

The compound [NH4(NH3)4][B(C6H5)4].NH3 (1) was prepared by the reaction of NaB(C(6)H(5))(4) with a proton-charged ion-exchange resin in liquid ammonia. [NH(4)(NH(3))(4)][Ca(NH(3))(7)]As(3)S(6).2NH(3) (2) and [NH4(NH3)4][Ba(NH3)8]As3S6.NH3 (3) were synthesized by reduction of As(4)S(4) with Ca and Ba in liquid ammonia. All ammoniates were characterized by low-temperature single-crystal X-ray structure analysis. They were found to contain the ammine-ammonium complex with the maximal possible number of coordinating ammonia molecules, the [NH4(NH3)4]+ ion. 1 contains a special dimer, the [(NH4(NH3)4)2(mu-NH3)2]2+ ion, which is formed by two[NH4(NH3)4]+ ions linked by two ammonia molecules. The H(3)N-H...N hydrogen bonds in all three compounds range from 1.82 to 2.20 A (DHA = Donor-H...Acceptor angles: 156-178 degrees). In 2 and 3, additional H(2)N-H...S bonds to the thioanions are observed, ranging between 2.49 and 3.00 A (DHA angles: 120-175 degrees). Two parallel phenyl rings of the [B(C(6)H(5))(4)](-) anion in 1 form a pi...pi hydrogen bond (C...C distance, 3.38 A; DHA angles, 82 degrees), leading to a dimeric [B(C6H5)4]2(2-) ion.     

Isotype Strukturen einiger Hexaamminmetall(II)-halogenide von 3d-Metallen: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 und [Ni(NH3)6]Cl2

The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH₃)₆]I₂, [Cr(NH₃)₆]I₂, [Mn(NH₃)₆]Cl₂, [Fe(NH₃)₆]Cl₂, [Fe(NH₃)₆]Br₂, [Co(NH₃)₆]Br₂ and [Ni(NH₃)₆]Cl₂ Crystals of yellow [V(NH₃)₆]I₂ and green [Cr(NH₃)₆]I₂ were obtained by the reaction of VI₂ and CrI₂ with liquid ammonia at room temperature. Colourless crystals of [Mn(NH₃)₆]Cl₂ were obtained from Mn and NH₄Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH₃)₆]Cl₂ and [Fe(NH₃)₆]Br₂ were obtained by the reaction of FeCl₂ and FeBr₂ with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH₃)₆]Br₂ were obtained from [Co₂(NH₂)₃(NH₃)₆]Br₃. Purple crystals of [Ni(NH₃)₆]Cl₂ were obtained by the reaction of NiCl₂ · 6H₂O and NH₄Cl with aqueous NH₃ solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K₂[PtCl₆] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.     

Die Einwirkung von Ammoniumfluorid auf Scandium: Synthese und Kristallstrukturen von (NH4)3[ScF6] und [Cu(NH3)4]3[ScF6]2

Action of Ammonium Fluoride on Scandium: Synthesis and Crystal Structures of (NH₄)₃[ScF₆] and [Cu(NH₃)₄]₃[ScF₆]₂ The action of (NH₄)F on scandium in copper ampoules yields either (NH₄)₃[ScF₆] or ScF₃ and a small quantity of [Cu(NH₃)₄]₃[ScF₆]₂, respectively, depending upon the molar ratio of the educts (NH₄)F : Sc (6 : 1 and 4 : 1, respectively) and temperature. (NH₄)₃[ScF₆] crystallizes with the cryolite type of structure: monoclinic, P2₁/n, Z = 2; a = 650.0(2); b = 651.4(2); c = 949.0(2) pm; β = 90.40(2)°, [Cu(NH₃)₄]₃[ScF₆]₂ is triclinic, P‐1, Z = 1; a = 821.1(2); b = 821.2(2); c = 822.7(2) pm; α = 90.04(3); β = 90.00(3); γ = 90.16(3)°. In its chemical behaviour against (NH₄)F, scandium parallels aluminium rather than gallium.     

[Pd(NH3)4][Ir0.5Os0.5Cl6] Solid Solution: Synthesis and Properties

[Pd(NH₃)₄][Ir_0.5Os_0.5Cl₆] solid solution, isomorphic to [Pd(NH₃)₄][IrCl₆], is synthesized and studied by X-ray powder diffraction and elemental analyses, IR and Raman spectroscopies.     

Double complex salts [Ni(NH3)6]3[Fe(CN)6]2 and [Ni(NH3)6]3[Cr(CNS)6]2: Synthesis and properties

The double complex salts [Ni(NH₃)₆]₃[Fe(CN)₆]₂ and [Ni(NH₃)₆]₃[Cr(CNS)₆]₂ were synthesized and their thermal decomposition in air was studied. The values of interplanar distances in crystal lattices were determined. The compounds are proposed as precursors for producing homogeneous bimetallic nanodimensional powders.     

Synthese und Kristallstrukturen von NH4[Si(NH3)F5] und [Si(NH3)2F4]

Synthesis and Crystal Structures of NH₄[Si(NH₃)F₅] and [Si(NH₃)₂F₄] Single crystals of NH₄[Si(NH₃)F₅] and [Si(NH₃)₂F₄] are obtained by reaction of silicon powder with NH₄HF₂ in sealed Monel ampoules at 400°C. NH₄[Si(NH₃)F₅] crystallizes with the tetragonal space group P4/n (no. 85) with a = 614.91(7) pm, c = 721.01(8) pm, Z = 2. Characteristic for the structure is the anionic octahedron [Si(NH₃)F₅]^?. Si(NH₃)₂F₄ crystallizes with the monoclinic space group P2₁/c (no. 14) with a = 506.9(1) pm, b = 728.0(1) pm, c = 675.9(1), β = 93,21(2)°, Z = 2. Trans-[Si(NH₃)₂F₄] molecules are characteristic for this structure.     

Cubane Tellurido Clusters [Zn(NH3)4]3[Mo4Te4(CN)12] and [Cd(NH3)4]3[W4Te4(CN)12]: Syntheses and Crystal Structures

Single crystals of [Zn(NH₃)₄]₃[Mo₄Te₄(CN)₁₂] (I) and [Cd(NH₃)₄]₃[W₄Te₄(CN)₁₂] (II) were obtained by applying solutions of K₇[Mo₄Te₄(CN)₁₂] · 11H₂O and K₆[W₄Te₄(CN)₁₂] · 5H₂O in aqueous ammonia over solutions of ZnCl₂ and Cd(NO₃)₂ in glycerol and were characterized by X-ray diffraction analysis. The IR spectra and thermal properties of compounds I and II were examined.     

Synthese und Kristallstruktur von Na10[P4(NH)6N4](NH2)6(NH3)0,5 mit dem adamantanartig aufgebauten Anion [P4(NH)6N4]4−

Synthesis and Crystal Structure of Na₁₀[P₄(NH)₆N₄](NH₂)₆(NH₃)_0.5 with an Adamantane-like Anion [P₄(NH)₆N₄]^4? Crystals of Na₁₀[P₄(NH)₆N₄](NH₂)₆(NH₃)_0.5 were obtained by the reaction of P₃N₅ with NaNH₂ (molar ratio 1:20) within 5 d at 600°C in autoclaves. The following data characterize X-ray investigations: Fm3 m, Z = 8, a = 15.423(2) Å, Z(F) = 261 with F ≥ 3 σ(F) Z(Variables) = 27, R/R_w = 0.086/0.089 The compound contains the hitherto unknown anion [P₄(NH)₆N₄]^4?, which resembles adamantane. The total structure can be described as follows: The centers of gravity of units of [Na₈(NH₂)₆(NH₃)]²⁺ – 8Na⁺ on the corners of a cube, 6NH₂^? on the ones of an inscribed octahedron with NH₃ in the center – follow the motif of a cubic-closest packed arrangement. Units of [Na₁₂(NH₂)₆]⁶⁺ – 12Na⁺ on the corners of a cuboctahedron and 6NH₂^? on the ones of an inscribed octahedron – occupy all octahedral and those of [P₄(NH)₆N₄]^4? all tetrahedral sites.     

Thermal Decomposition of (NH4)2[Mo3S(S2)6] · nH2O

The thermal decomposition of (NH₄)₂[Mo₃S(S₂)₆] · nH₂O was studied by DTA/TG, infrared spectroscopy, X-ray diffraction, determination of specific surfaces and temperature programmed desorption measurements. The results are reported and discussed with respect to the stability of the Mo^IV-triangle system which is retained during the thermal treatment up to the formation of hexagonal MoS₂, which can be understood nicely from a mechanistic point of view.     

Die Ammonolyse von (NH4)2GeF6. Darstellung und Struktur von NH4[Ge(NH3)F5]

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.     

Synthese und Kristallstruktur von [Cr(NH3)6][Cr(NH3)2F4][BF4]2

Synthesis and Crystal Structure of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂ The action of ammonium fluoride on a mixture of boron and chromium in a sealed Monel ampoule at 300 °C yields single crystals of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂. The crystal structure (tetragonal, P4/mbm, Z = 2, a = 1056.0(1), c = 781.7(1) pm; R₁ = 0.0414; wR₂ = 0.1087 for 411 reflections with I₀ > 2σ(I)) contains [Cr(NH₃)₆]³⁺ and [Cr(NH₃)₂F₄]^– octahedra and twice as many [BF₄]^– tetrahedra that are arranged in a quadrupled super‐structure of the CsCl‐type of structure.     

ChemInform Abstract: Synthesis and Crystal Structure of [Cr(NH3)6] [Cr(NH3)2F4][BF4]2.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

Thermolysis of [Co(NH3)6][Cr(C2O4)3]

Thermolysis of the double-metal complex [Co(NH₃)₆][Cr(C₂O₄)₃] was studied in air at 200, 350, and 500°C and in a hydrogen atmosphere at 200, 350, 500, 700, and 900°C, as well as the composition and properties of thermolysis products. Oxidative thermolysis produces mixed oxides CoCr₂O₄ and Co₂CrO₄; reductive thermolysis produces Co + Cr₂O₃ mixture. Specific surface areas were measured for reductive thermolysis products; the maximal specific surface area and, therefore, maximal dispersion are reached at 500°C. The morphology of the reductive thermolysis products and the thermolysis chemism were studied in relation to the nature of the complex anion.     

UF6 and UF4 in Liquid Ammonia: [UF7(NH3)]3− and [UF4(NH3)4]

From the reaction of uranium hexafluoride UF₆ with dry liquid ammonia, the [UF₇(NH₃)]^3? anion and the [UF₄(NH₃)₄] molecule were isolated and identified for the first time. They are found in signal‐green crystals of trisammonium monoammine heptafluorouranate(IV) ammonia (1:1; [NH₄]₃[UF₇(NH₃)] ? NH₃) and emerald‐green crystals of tetraammine tetrafluorouranium(IV) ammonia (1:1; [UF₄(NH₃)₄] ? NH₃). [NH₄]₃[UF₇(NH₃)] ? NH₃ features discrete [UF₇(NH₃)]^3? anions with a coordination geometry similar to a bicapped trigonal prism, hitherto unknown for U^IV compounds. The emerald‐green [UF₄(NH₃)₄] ? NH₃ contains discrete tetraammine tetrafluorouranium(IV) [UF₄(NH₃)₄] molecules. [UF₄(NH₃)₄] ? NH₃ is not stable at room temperature and forms pastel‐green [UF₄(NH₃)₄] as a powder that is surprisingly stable up to 147 °C. The compounds are the first structurally characterized ammonia complexes of uranium fluorides.     

Darstellung und Strukturaufklärung von Ammonium‐tetraamminlithium‐amidotrithiophosphat‐Ammoniak(1/1) (NH4) [Li(NH3)4] [P(NH2)S3] · NH3

Synthesis and Crystal Structure of Ammonium Tetraamminelithium Amidotrithiophosphate‐Ammonia(1/1)(NH₄)[Li(NH₃)₄][P(NH₂)S₃]·NH₃ Colourless crystals of (NH₄)[Li(NH₃)₄][P(NH₂)S₃]·NH₃ were prepared by the reduction of P₄S₁₀ with a solution of lithium in liquid ammonia. The X‐ray structure determination shows them to contain the pseudo‐tetrahedral amidotrithiophosphate anion [P(NH₂)S₃]²⁻ (point group C_S), which is the hitherto unknown final member of a series of previously characterized amidothiophosphates. The ammonium ion and the ammonia molecule of solvation form an diamminehydrogen(1+)‐ion N₂H₇⁺ with a short, nearly linear hydrogen bond of 2.864(3) Å.     

Derivate des Flußspat-Typs: [Fe(NH3)6][TaF6]2 und [Ni(NH3)6][TaF6]2

Derivatives of the Fluorite Type: [Fe(NH₃)₆][TaF₆]₂ and [Ni(NH₃)₆][TaF₆]₂ Light blue single crystals of [Fe(NH₃)₆][TaF₆]₂ and [Ni(NH₃)₆][TaF₆]₂ are obtained from 36 : 1 : 6 molar mixtures of (NH₄)F, iron/nickel and tantalum powders, respectively, in sealed Monel metal ampoules at 400 °C. They both crystallize isotypic with [Co(NH₃)₆][PF₆]₂ (cubic, Fm-3m, Z = 4, a = 1259.0(2)/1260.4(2) pm) in a structure that can be derived from the basic fluorite-type of structure according to [Ca][F]₂≡[Fe(NH₃)₆][TaF₆]₂, for example.