Investigation of peroxyhydrates and hydrates of rubidium and cesium carbonates Communication 2. Physicochemical study of the ternary system Rb2CO2-H2O2-H2O

Conclusions A physicochemical investigation of the system Rb₂CO₃-H₂O₂-H₂O in the region of high hydrogen peroxide concentrations at low temperatures revealed for the first time the formation of a peroxyhydrate with a high hydrogen peroxide content, of the composition Rb₂CO₃ · 6H₂O₂.     

Untersuchung der Cokristallisation in den Systemen. Mn(OOCCH3)2-Co(OOCCH3)2-H2O,Mn(OOCCH3)2-Ni(OOCCH3)2-H2O,Mn(OOCCH3)2-Zn(OOCCH3)2-H2O bei 60°C

Investigation of Cocrystallization in the Systems Mn(OOCCH₃)₂-Co(OOCCH₃)₂-H₂O, Mn(OOCCH₃)₂-Ni(OOCCH₃)₂-H₂O, Mn(OOCCH₃)₂-Zn(OOCCH₃)₂-H₂O at 60°C The three-component systems Mn(OOCCH₃)₂-Co(OOCCH₃)₂-H₂O, Mn(OOCCH₃)₂-Ni(OOCCH₃)₂-H₂O and Mn(OOCCH₃)₂-Zn(OOCCH₃)₂-H₂O at 60°C were investigated by physio-chemical analysis. There is an interruption in the series of mixed crystals formed in the three-component systems. The inclusion of Co²⁺- and Ni²⁺ in Mn(OOCCH₃)₂ · 2 H₂O of Mn²⁺ in Co(OOCCH₃)₂ · 2 H₂O, Zn(OOCCH₃)₂ · 2 H₂O and Ni(OOCCH₃)₂ · 4 H₂O is based on isodimorphic substitution. It was found that in the system Mn(OOCCH₃)₂-Zn(OOCCH₃)₂-H₂O crystallizes Zn(OOCCH₃)₂ · Mn(OOCCH₃)₂ · 2 H₂O. It was identified by the X-ray and differential thermal analysis.     

Die Kristallstruktur des Natriumoxohydroxoaluminathydrates Na2[Al2O3(OH)2] · 1,5 H2O

The Crystal Structure of the Sodium Oxohydroxoaluminate Hydrate Na₂[Al₂O₃(OH)₂] · 1.5 H₂O The crystal structure of the sodium oxohydroxoaluminate hydrate Na₂[Al₂O₃(OH)₂] ·s 1.5 H₂O (up to now described as Na₂O · Al₂O₃ · 2.5 H₂O and Na₂O · Al₂O₃ · 3 H₂O, respectively) was solved. The X-ray single crystal diffraction analysis (tetragonal, space group P-42₁m, a = 10.522(1) Å, c = 5.330(1) Å, Z = 4) results in a polymeric layered structure, consisting of AlO_3/2(OH) tetrahedral groups. Between these layers the Na⁺ ions are situated, which form tetrameric groups of face-linked NaO₆ octahedra. The involved O^2? ions are due to Al? O? Al bridges, Al? OH groups and water of crystallization. ²⁷Al and ²³Na MAS NMR investigations confirm the crystal structure analysis. The relations between the crystallization behaviour of the compound and the constitution of the aluminate anions in the corresponding sodium aluminate solution and in the solid, respectively, are discussed.     

Surface tension of CaO-Al2O3, CaO-SiO2, and CaO-Al2O3-SiO2 melts

A method for the approximation of the temperature-concentration dependence of the surface tension of CaO-Al₂O₃, CaO-SiO₂, and CaO-Al₂O₃-SiO₂ melts was suggested. The method was based on the statistical-thermodynamic model of associated solutions. A comparison of the calculated surface tensions of the melts with the available literature data showed that the suggested approach allowed the surface tension of liquid slags to be correctly predicted as a function of temperature and composition.     

[Mo4O4(μ-S)4(μ-OH)2(μ-H2O)(H2O)2(pba)]2−: An Original Coordination Mode for the Ligand 1,3-Propylenebis(Oxamate)

The novel polyoxothioanion [Mo₄S₄O₄(OH)₂(OH₂)₃pba]^2? where pba^4? ligand is the 1,3-propylenebis(oxamate), was prepared by reacting Mo₁₂S₁₂O₁₂(OH)₁₂(OH₂)₆ ring with [Cu-pba]^2? in aqueous medium. NaK[Mo₄O₄(μ-S)₄(μ-OH)₂(μ-H₂O)(H₂O)₂(pba)] ·7H₂O was isolated in the solid state and fully characterized by X-ray diffraction study (tetragonal, P4(2)/m [a=20.4962(4) Å; b=20.4962(4) Å; c=14.7013(5) Å). The molecular structure consists of an arc cycle shape tetranuclear enchainment {Mo₄S₄O₄(OH)₂ (OH₂)₃} closed by a pba^4? ligand. The 3-D packing, resulting from the connection between K⁺ and Na⁺ and the coordination complex {Mo₄-pba]^2? is described. The ¹H-NMR characterization of the complex in aqueous solution is given. The ¹H-NMR spectrum exhibits four signals assigned to four enantiotopic protons of the alkyl chain of the pba^4? ligand and is in agreement with crystal structure of the complex [Mo₄-pba]^2?. The compound was also characterized by infrared spectroscopy.     

ChemInform Abstract: Cross Sections and Product Kinetic Energy Analysis of H2O+-H2O Collisions at Suprathermal Energies.

The H₂O⁺-H₂O reaction is studied at center-of-mass collision energies in the range 0.5-25 eV.     

Solubility in the systems KClO4-RbClO4-H2O,KBrO3-RbBrO3-H2O,KIO3-CsIO3-H2O,RbClO4-CsClO4-H2O,RbBrO3-CsBrO3-H2O,RbIO3-CsIO3-H2O at 25°

Conclusions The solubility in the systems KClO₄-RbClO₄-H₂O, KBrO₃-RbBrO₃-H₂O, KIO₃-CsIO₃-H₂O, RbClO₄-CsClO₄-H₂O, RbBrO₃-CsBrO₃-H₂O, RbIO₃-CsIO₃-H₂O was studied at 25°. In all cases the formation of continuous series of solid solutions was established.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2631–2634, December, 1971.The authors would like to express their gratitude to A. I. Vulikh for his constant interest in this work and his valuable advice.     

Tripotassium tris­(oxalato‐κ2O,O′)­aluminate bis(hydrogen peroxide) hydrate,the first example of a cyclic hydrogen‐bonded H2O2 dimer

In addition to associating into cyclic hydrogen‐bonded dimers [O⋯O = 2.663 (1) and 2.914 (1) Å], each hydrogen peroxide mol­ecule in the title structure, K₃[Al(C₂O₄)₃]·1.75H₂O₂·0.25H₂O, hydrogen bonds to a neighbouring oxalate ligand [O⋯O = 2.700 (1) and 2.730 (1) Å] and coordinates to two K⁺ ions [K⋯O = 2.6620 (9)–2.8380 (7) Å].     

Kristallstruktur von LiHC2O4-H2O

LiHC₂O₄ · H₂O crystallizes in space group P 1 with a₀ = 4.99, b₀ = 6.16, c₀ = 3.45 Å; α₀ = 96.3°, β₀ = 98.0°, γ₀ = 80.4° and Z = 1. The crystal structure has been determined by direct methods. Refinement by least squares methods resulted to R₁ = 8,3%. In the structure the oxalate group is not planar. The angle between the two O? C? O planes is 2.9°.     

The application of <Emphasis Type="Italic">in situ</Emphasis> X-ray diffraction for the study of mineral reactions: The formation of lawsonite at 400°C and 25 kbar

The method of in situ X-ray diffraction with the influence of temperature and pressure on the sample was successfully applied in Siberian Synchrotron and Terahertz Radiation Centre on the experimental station Diffractometry in hard X-rays. High-pressure water-containing lawsonite silicate CaAl₂[Si₂O₇](OH)₂·H₂O is obtained at 400°C and 25 kbar in a diamond anvil cell during the decomposition of laumontite. In situ diffractometry of the reaction products helps to determine parameters of the unit cell of lawsonite and phase composition of CaO-Al₂O₃-SiO₂-H₂O at 400°C and 25 kbar.     

AlIII-Phthalocyanine: Darstellung,Eigenschaften und Kristallstruktur von Tetra(n-butyl)ammonium-trans-di(nitrito(O))phthalocyaninato(2−)aluminat(III)

Al^III Phthalocyanines: Synthesis, Properties, and Crystal Structure of Tetra(n-butyl)-ammonium-trans-di(nitrito(O))phthalocyaninato(2?)aluminate(III) [Al(Cl)Pc^2?] reacts with excess (ⁿBu₄N)NO₂ in dimethylformamide yielding less soluble blue tetra(n-butyl)ammonium-trans-di(nitrito(O))phthalocyaninato(2?)aluminate(III), (ⁿBu₄N)^trans[Al(ONO)₂Pc^2?], which crystallizes in the monoclinic space group C2/c (No. 15) with Z = 4. The Al atom is in the special position 4 d in the center of the Pc^2? ligand and the two nitrit ions are monodentate O-coordinated in a mutually trans arrangement to the Al atom. The Al? O and average Al? N_iso bond distances are 1.927(2) and 1.956 Å, respectively. The geometric data of the coordinated nitrite ion are: d(N? O) = 1.277(4) Å; d(N? O) = 1.221(4) Å; ?(O? N? O) = 114.3(3)°; ?(Al? O? N) = 121.3(2)°. The non-bonded O atoms are trans to the Al atom. The Pc^2? ligand is slightly ruffled. The UV-VIS-NIR spectra and the vibrational spectra are discussed.     

Glass formation in the Al(IO3)3-Al2(SO4)3-H2O system

Glass-formation boundaries in the Al(IO₃)₃-Al₂(SO₄)₃-H₂O system are determined. The IR spectra of glassy and crystalline Al(IO₃)₃ · 8H₂O samples are measured. The structure and properties of glassy Al(IO₃)₃ · 10H₂O are compared to those of glassy Al₂(SO₄)₃ · 10H₂O.     

Physicochemical study on selenites of the three-component system Yb2O3-SeO2-H2O

The solubility isotherm of the three-component system Yb₂O₃-SeO₂-H₂O at 100°C was studied. There are two fields of crystallization in the solubility diagram at this temperature - a small one of Yb₂(SeO₃)₃·4H₂O and a large one of YbH(SeO₃)₂·2H₂O. These compounds were identified by the Schreinemakers' method, and by chemical and X-ray analyses as well. Simultaneous TG and DTA curves of the two compounds obtained were made and the mechanism of the thermal decomposition was described. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermische Zersetzung von Afwillit Ca3(SiO3OH)2 · 2 H2O

Thermal Decomposition of Afwillite Ca₃(SiO₃OH)₂ · 2 H₂O Using the molybdate method [1], infrared, Raman, and high resolution solid state ¹H and ²⁹Si NMR spectroscopy two intermediate phases can be identified in the process of dehydration of afwillite: At temperatures of 250 to 300°C a non-crystalline phase is formed mainly (about 80 to 90% referred to Si) with a structure similar to mineral killalaite Ca₃OH(Si₂O₆OH) [2] and phase F [3]. Between 300 and 500°C this compound is converted to a non-crystalline kilchoanite-like phase γ-Ca₂SiO₄ · Ca₄Si₃O₁₀ [4], consisting of ordered γ-Ca₂SiO₄ and disordered trisilicate layers. By a side reaction polysilicate (about 10 to 20% referred to Si) is formed.     

Zur Koordination des Aluminiums in den Calciumaluminathydraten 2 CaO · Al2O3 · 8 H2O und CaO · Al2O3 · 10 H2O

On the Coordination of Al in the Calcium Aluminate Hydrates 2 CaO · Al₂O₃ · 8 H₂O and CaO · Al₂O₃ · 10 H₂O By investigations with high-resolution ²⁷Al-NMR in solids it is shown that in the compound 2 CaO · Al₂O₃ · 8 H₂O the Al merely exist in octahedral coordination. According to this and considering its structural relationship with 4 CaO · Al₂O₃ · 19 H₂O the dicalcium aluminate hydrate is proposed to be formulated as [Ca₂Al(OH)₆][Al(OH)₃ (H₂O)₃]OH. Likewise for the compound CaO · Al₂O₃ · 10 H₂O the octahedral coordination of the Al is proved by ²⁷Al-NMR. This result corresponds with literature according to which a constitution as cyclohexaaluminate Ca₃[Al₆(OH)₂₄] · 18 H₂O is proposed.     

Interaction in the Li2Mo3O10-CO(NH2)2-H2O system at 25°C

The solubilities and solid phases in the Li₂Mo₃O₁₀-CO(NH₂)₂-H₂O system at 25°C are studied. A compound of composition Li₂Mo₃O₁₀ · 6CO(NH₂)₂ · 4H₂O and lithium trimolybdate decahydrate Li₂Mo₃O₁₀ · 10H₂O are found to exist. The Li₂Mo₃O₁₀ · 6CO(NH₂)₂ · 4H₂O ray crosses the solubility isotherm, which indicates the congruent solubility of the double compound in water. The density, refractive index, dynamic viscosity, surface tension, electrical conductivity, and pH of saturated solutions of the system are determined. The molar volume, equivalent electrical conductivity, reduced conductivity, and solution ionic strength isotherms are calculated. A strong correlation between all the property isotherms and the solubility is observed.     

Pr10[Si10−xAlxO9+xN17−x]Cl with x ≈ 1 – an Oxonitridoaluminosilicate Chloride

The oxonitridoaluminosilicate chloride Pr₁₀[Si_10?xAl_xO_9+xN_17?x]Cl was obtained by the reaction of praseodymium metal, the respective chloride, AlN and Al(OH)₃ with “Si(NH)₂” in a radiofrequency furnace at temperatures around 1900 °C. The crystal structure was determined by single‐crystal X‐ray diffraction (Pbam, no. 55, Z = 2,a = 10.5973(8) Å, b = 11.1687(6) Å, c = 11.6179(7) Å, R1 = 0.0337). The sialon crystallizes isotypically to the oxonitridosilicate halides Ce₁₀[Si₁₀O₉N₁₇]Br, Nd₁₀[Si₁₀O₉N₁₇]Br and Nd₁₀[Si₁₀O₉N₁₇]Cl, which represent a new layered structure type. The structure refinement was performed utilizing an O/N‐distribution model according to Paulings rules, i.e. nitrogen was positioned on all bridging sites and mixed O/Noccupation was assumed on the terminal sites resulting in charge neutrality of the compounds. The Si and Al atoms were refined equally distributed on their three crystallographic sites, due to their poor distinguishability by X‐ray analysis. The tetrahedra layers of the structure consist of condensed [(Si,Al)N₂(O,N)₂] and [(Si,Al)N₃(O,N)] tetrahedra of Q² and Q³ type. The chemical composition of the compound was derived from electron probe micro analyses (EPMA).     

Phase formation in the ZrO(NO3)2-H3PO4-CsF(HF)-H2O system

The phase formation in the system ZrO(NO₃)₂-H₃PO₄-CsF(HF)-H₂O was studied at the molar ratio CsF/Zr = 1 along the sections PO ₄ ^3? /Zr = 0.5 and 1.5 at a ZrO₂ concentration in the initial solution of 2?C14 wt %. The following compounds were isolated: Cs₅Zr₄F₂₁ · 3H₂O, CsZr₂(PO₄)₃ · 2HF · 2H₂O, CsZrF₂PO₄ · H₂O, CsZr₂F₆PO₄ · 4H₂O (for the first time), CsHZrF₃PO₄ (for the first time), Cs_0.70ZrF(PO₄)_1.23 · nH₂O, and CsHZr₂F₂(P_O4)_2.66 · nH₂O. The compositions of CsZrF₂PO₄ · H₂O, Cs_0.70ZrF(PO₄)_1.23 · nH₂O, and CsHZr₂F₂(PO₄)_2.66 · nH₂O are conditional. All the compounds were characterized by crystal-optical, X-ray powder diffraction, thermal analyses, and IR spectroscopy. The formula CsHZrF₃PO₄ was established by energy-dispersive analysis with a LEO-1450 scanning electron microscope and an MS-46 CAMECA X-ray microanalyzer.     

Nonanatrium-bis(hexahydroxoaluminat)-trihydroxid-hexahydrat (Na9[Al(OH)6]2(OH)3 · 6H2O) – Kristallstruktur,NMR-Spektroskopie und thermisches Verhalten

Nonasodium Bis(hexahydroxoaluminate) Trihydroxide Hexahydrate (Na₉[Al(OH)₆]₂(OH)₃ · 6H₂O) – Crystal Structure, NMR Spectroscopy and Thermal Behaviour The crystal structure of the nonasodium bis(hexahydroxoaluminate) trihydroxide hexahydrate Na₉[Al(OH)₆]₂(OH)₃ · 6H₂O (4.5 Na₂O Al₂O₃ · 13.5 H₂O) (up to now described as 3 Na₂O · Al₂O₃ · 6H₂O, 4Na₂O · Al₂O₃ · 13 H₂O and [3 Na₂O · Al₂O₃ · 6H₂O] [xNaOH · yH₂O], respectively) was solved. The X-ray single crystal diffraction analysis (triclinic, space group P1 , a = 8.694(1) Å, b = 11.344(2) Å, c = 11.636(3) Å, α = 74.29(2)°, β = 87.43(2)°, γ = 70.66(2)°, Z = 2) results in a structure, consisting of monomeric [Al(OH)₆]^3? aluminate anions, which are connected by NaO₆ octahedra groups. Furthermore the structure contains both, two hydroxide anions only surrounded by water of crystallization and OH groups of [Al(OH)₆]^3? aluminate anions and a hydroxide anion involved in three NaO₆ coordination octahedra directly and moreover connected with a water molecule by hydrogen bonding. The results of ²⁷Al and ²³Na-MAS-NMR investigations, the thermal behaviour of the compound and possible relations between the crystal structure and the conditions of coordination in the corresponding sodium aluminate solution are discussed as well.     

Glass formation in the systems Al2(SO4)3-MSO4-H2O (M = Cd2+, Zn2+, Mg2+) and Al2(SO4)3-Fe2(SO4)3-H2O

The glass formation region boundaries were found in the systems Al₂(SO₄)₃-MSO₄-H₂O, where M = Cd²⁺, Zn²⁺, and Mg²⁺, and Al₂(SO₄)₃-Fe₂(SO₄)₃-H₂O. The causes of the differences in glass-forming ability between the studied systems were analyzed. The structures and properties of glassy Al₂(SO₄)₃ · 11H₂O and Fe₂(SO₄)₃ · 11H₂O were compared.