The hydrates of sodium metasilicate peroxyhydrates

Summary A study of solubility in the system Na₂SiO₃-H₂O₂-H₂O at 0 and 15° has shown that sodium metasilicate forms a number of compounds with the general formula Na₂SiO₃· ·xH₂O₂·yH₂O, where x=2.5–3 and y=0–1.     

Chemical recovery of thallium-203 following production and separation of lead-201

Because of the cost and limited availability of isotopically enriched thallium (>92%²⁰³Tl), its use in the²⁰³Tl(p, 3n)²⁰¹Pb nuclear reaction necessitates chemical recovery. An adaptive method has been developed and evaluated. After the separation of²⁰¹Pb, the²⁰³Tl(I) is oxidized to²⁰³Tl(III) by Cl₂, Br₂ or [Fe(CN)₆]⁻², precipitated as Tl(OH)₃ with NaOH and subsequently converted to Tl₂O₃ by heating. Due to potential loss during recovery, the solubilities of Tl(OH)₃ and Tl₂O₃ in aqueous solution as a function of pH have been studied using the internal tracer²⁰²Tl (T=12.2d), produced during cyclotron irradiation. Effective solubility product constants have been determined to be 5.4·10⁻⁴⁸ and 2.5·10⁻⁴⁷ for Tl(OH)₃ and Tl₂O₃, respectively.     

Study of systems containing concentrated hydrogen peroxide

Summary Investigation of the ternary system Mg(OH)₂-H₂O₂-H₂O at O° and at +29° by the solubility method over a wide range of concentrations of H₂O₂ established the possibility of existence of three individual peroxy compounds of magnesium with the compositions: MgO₂:MgO₂·O.5H₂O and MgO₂·H₂O.     

Two-dimensional thallium(I) supramolecular polymer constructed from Tl?π interactions: A new precursor for the preparation of thallium(III) oxide with a nano-structural surface

A new two-dimensional thallium(I) supramolecular polymer, [Tl₂(μ₃-9-Ac)(μ₄-9-Ac)(H₂O)]_n (1) [9-HAc = 9-anthracene carboxylic acid]_, has been synthesized and characterized. The single-crystal X-ray data of compound 1 shows two types of Tl^I ions with coordination numbers of four and five. The thallium atoms have irregular coordination spheres, containing a stereo-chemically active lone pair with η⁵ Tl?C interactions in the vacant coordination sphere of the Tl^I ions, thus attaining total hapticities of 9 and 10 with O₅Tl1?C₅ and O₄Tl2?C₅ environments and Tl?π_(centroid) distances of 3.308 and 3.251 Å, respectively. The thermal stability of 1 was studied by thermo gravimetric (TG) and differential thermal analyses (DTA). Different morphologies of thallium(III) oxide with a nano-structural surface were prepared from compound 1 powders and compound 1 micro-rods. These nano-structures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM).     

Thallium(I)-Uranates(VI)

The solid state preparation, thermal and hydrolytic characteristics of thallium(I)—uranates(VI) are described. The phases identified were Tl₂UO₄, Tl₂U₂O₇ and a range of solid solution (Tl₂O. 2,33 UO₃? Tl₂O. 6 UO₃). The thallium uranates are isostructural with the corresponding potassium uranates. Tl₂U₂O₇ is the stable phase formed from the other uranates on hydrolytic treatment. The thallium uranates lose thallium(I) oxide on heating to temperatures above 750°C and the order of thermal stability is Tl₂U₆O₁₉～Tl₂U₃O₁₀～Tl₂U₂O₇»Tl₂UO₄.     

Über die Löslichkeit von Na2SeO4 und das Verhalten von Na2SeO4·10H2O in organischen Lösungsmitteln

Zusammenfassung Untersucht wurde die Löslichkeit von Na₂SeO₄ in den organischen Lösungsmitteln CH₃OH, C₂H₅OH,n-C₃H₇OH und Aceton bei 20°, 30°, 40°, 50°C und die Dichte der so erhaltenen gesätt. Lösungen bestimmt. Das Verhalten von Na₂SeO₄·10 H₂O zu diesen organischen Lösungsmitteln zeigte Entwässerung zu Na₂SeO₄ in CH₃OH und C₂H₅OH, während bein-C₃H₇OH und Aceton der Entwässerungsprozeß nicht zu Ende geht. Es wurde auch die Löslichkeit von Na₂SeO₄·10 H₂O in obigen Lösungsmitteln sowie die Dichte der Lösungen bestimmt.

---

The solubility of Na₂SeO₄ and the behaviour of Na₂SeO₄·10H₂O in organic solvents

The solubility of Na₂SeO₄ in the organic solvents CH₃OH, C₂H₅OH,n-C₃H₇OH and acetone at 20°, 30°, 40° and 50°C has been determined, and the specific gravity of the solutions measured. The behaviour of Na₂SeO₄·10 H₂O in the same solvents was also studied. Dehydration to Na₂SeO₄ occurs in CH₃CH and C₂H₅OH, whereas inn-C₃H₇OH and acetone, dehydration is incomplete. The solubility of Na₂SeO₄·10 H₂O in these solvents and the specific gravity of the solutions have also been determined.

     

Über die Thalliumgermanate Tl2Ge4O9 und Tl2Ge6O13

Zusammenfassung Nach Dehydratation des Germanat-Zeoliths Tl₃HGe₇O₁₆· · 4 H₂O bildet sich bei 650°C das zu Me₂Ge₄O₉ (Me=Na, K, Rb) isotype Thalliumtetragermanat. Durch Entwässerung bei 700°C entsteht aus dem Zeolith ein stabiles Hexagermanat Tl₂Ge₆O₁₃, welches auch aus Schmelzen der Zusammensetzung Tl₂O:GeO₂=1:6 gewonnen wird. Mit Hilfe von DK- undWeissenberg-Aufnahmen werden für die rhombische Elementarzelle die Gitterparameter:a=37,24₇,b=13,74₃ undc=4,73₃ kX·E. ermittelt. Wahrscheinliche Raumgruppe ist D _2h ¹⁷ .     

A thallium(I) tetranuclear cubic cage unit in an interpenetrated supramolecular polymer: A new precursor for the preparation of Tl2O3 nanostructures

A new thallium(I) supramolecular polymer, [Tl₄(μ₃-4-BN)₄]_n (1) [9-HBN = 4-hydroxy benzonitrile], with a disordered cubic cage structural unit has been synthesized and characterized. The single-crystal X-ray data of compound 1 shows one type of Tl^I ion in the tetranuclear cubic cage structure with a coordination number of three. In addition to two intra cage thallophilic interactions in 1, each thallium(I) atom has a weak Tl?N secondary interaction with the nitrile group of the 4-BN⁻ ligand. Finally the Tl-ions attain the O₃Tl?NTl₂ coordination sphere with a stereo-chemically ‘active’ electron lone pair on the metal. The self assembly between the benzonitrile groups of one cubic cage structure with an adjacent one with a Tl?N short contact, by π-π stacking and weak hydrogen bonding interactions, results in the formation of a new interpenetrating thallium(I) supramolecular polymer. The thermal stability of 1 was studied by thermo gravimetric (TG) and differential thermal analyses (DTA). Nanostructures of thallium(III) oxide were prepared from a calcination process of compound 1 fine powder at 743 K. These nanostructures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM).     

An isothermal (30 °C) study of heterogeneous equilibria in the sucrose (C12H22O11)-calcium hydroxide (Ca(OH)2)-water system

Solid-liquid equilibria in the C₁₂H₂₂O₁₁-Ca(OH)₂-H₂O system have been determined at 30 °C. Two phases C₁₂H₂₂O₁₁·3Ca(OH)₂ and C₁₂H₂₂O₁₁·2Ca (OH)₂ have been evidenced, and solubility (liquidus) curves have been determined. It is thus shown that these ternary phases exhibit incongruent solubilities at 30 °C. These solid phases were characterized using Infrared Spectroscopy (IR), Scanning Electron Microscopy (SEM) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES).     

Tl2D coordination polymer involving close Tl?π (aromatic) contacts, [Tl3(μ-BPC)2(μ-NO3)]n

A two-dimensional polymer, [Tl₃(μ-BPC)₂(μ-NO₃)]_n [BPC = biphenyl-2-carboxylate], has been synthesized and characterized. Its single-crystal X-ray structure shows three types of Tl^I-ions with coordination numbers of 5 (Tl1 and Tl2), and 4 (Tl3). Two of the thallium atoms, Tl1 and Tl3, contain close Tl^I?π (aromatic) contacts, thus attaining a total hapticity of 11 and 10 with environments Tl1O₅C₆ and Tl3O₄C₆, respectively.     

Thermal reactivity of sodium manganese decavanadates

The hydrates of sodium manganese decavanadates are thermally unstable: Na₄MnV₁₀O₂₈ ·19H₂O decomposes on dehydration to give Mn(VO₃)₂, NaVO₃ and NaV₃O₈, while Na₂Mn₂V₁₀O₂₈ · 20H₂O decomposes to Mn(VO₃)₂, NaVO₃, NaV₃O₈ and NaV₆O₁₅. At a lowern(Na) n(V) molar ratio in the starting compound, a product containing a bronze with a higher vanadium(IV) content is formed. The mixtures of products are stable in the temperature ranges 500–1000°C, and 610–1000°C, respectively.

---

Zusammenfassung Hydrate von Natrium-magnesiumdekavanadat sind thermisch instabil. Na₄MnV₁₀O₂₈·19H₂O zersetzt sich durch Dehydratierung in Mn(VO₃)₂, NaVO₃ und NaV₃O₈ und Na₂Mn₂V₁₀O₂₈ · 20H₂O in Mn(VO₃)₂, NaVO₃, NaV₃O₈ und NaV₆O₁₅. Bei einem niedrigerem n(Na)n(V) molarem Verhältnis der Ausgangsverbindungen wird ein Produkt geformt, welches eine Bronze mit einem höherem Vanadium(IV)-gehalt enthält. Das Produktegemisch ist im Temperaturbereich 500°–1000°C bzw. 610°–1000°C thermisch stabil.

     

Synthesis and Crystal Structure of the First Thallium Hydrous Nesosilicate Tl4SiO4·0.5H2O

Orange prismatic crystals of the first thallium hydrous nesosilicate Tl₄SiO₄·0.5H₂O have been obtained by evaporation from aqueous solution. There are three symmetrically independent Tl⁺ cations and five symmetrically independent oxygen atoms in the structure of Tl₄SiO₄·0.5H₂O. The O(4) and O(5) atoms belong to water molecules. Coordination polyhedra of the Tl⁺ cations are strongly distorted because of the stereoactive behavior of lone electron pairs. The structure of Tl₄SiO₄·0.5H₂O contains sheets of SiO₄ tetrahedra and Tl coordination polyhedra. The sheets have the composition [Tl₃SiO₄]^– and are parallel to [100]. Within the sheets, SiO₄ tetrahedra link to thallium polyhedra though common corners. The sheets are linked by dimers of face‐sharing Tl(3)O₅ polyhedra, thus providing interconnection of the sheets into a framework. The framework has large elliptical channels occupied by water molecules (OW2) and electron pairs of Tl⁺ cations.The comparison with some other M⁺ (M = K, Ag, Tl) silicates is given.     

205T1 NMR study of t1(III) ethylenediaminetetra acetates

Conclusions The²⁰⁵T1 NMR method was used to study the thallium ethylenediaminetetraacstates HTlA·2.5H₂O and Tl₂A·SO₄·10H₂O. Two signals, which were assigned to the inner and outer sphere cations, are observed for Tl₂A·SO₄·10H₂O. The thallium ions in T1₂A·SO₄·10H₂O are nonequivalent.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1195–1196, May, 1978.     

Physicochemical investigation of the ternary system KF-H2O2-H2O

Conclusions An investigation of the fusibility in the system KF-H₂O₂-H₂O confirmed the existence of KF · H₂O₂ and demonstrated the formation of a new compound, KF · 2H₂O₂, which exists in the system in the interval from –70 to 20° in the region of high hydrogen peroxide concentrations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 491–494, March, 1973.     

Phasenverhältnisse der Selenate im Dreistoffsystem Tl2O3-SeO3-H2O bei 100°C

Summary The solubility of the system Tl₂O₃-SeO₃-H₂O was studied at 100°C. The compounds obtained were subjected to X-ray and thermal analysis. The symmetry and the crystallographic constants of some of the compounds were determined.

     

Dreistoffsysteme Wasser-Salz mit Lithiumselenat,Natriumselenat, Cobaltselenat und Magnesiumselenat bei 25°C

The phase interaction in the systems Li₂SeO₄-CoSeO₄-H₂O, Li₂SeO₄-MgSeO₄-H₂O, and Na₂SeO₄-CoSeO₄-H₂O at 25°C was studied. The systems Li₂SeO₄-CoSeO₄-H₂O and Li₂SeO₄-MgSeO₄-H₂O were found to be of the simple eutectic type. The pure salts Li₂SeO₄·H₂O, CoSeO₄·6H₂O, Li₂SeO₄·H₂O, and MgSeO₄·6H₂O were found to crystallize from these systems. The formation of a new phase, a double salt of composition Na₂SeO₄·CoSeO₄·4H₂O in the system Na₂SeO₄-CoSeO₄-H₂O was established. The composition of the double salt obtained was identified by physico-chemical and derivatograph analysis. X-ray-phase analysis of the double salt was carried out.

     

Diagramme de phases du système Tl2OMoO3

Six thallium(I) molybdates with numerous allotropic modifications have been found in the binary system Tl₂OMoO₃; Tl₄MoO₅, Tl₂Mo₂O₇, Tl₈Mo₁₀O₃₄ (three forms), and Tl₂Mo₇O₂₂ (two forms) melt incongruently; Tl₂MoO₄ and Tl₂Mo₄O₁₃ which are trimorphic melt congruently. For the most part, the compounds were characterized by their powder diagram and by their IR spectrum which allowed comparisons with alkaline molybdates.     

Guest editor's tribute to Friedrich Baucke on the occasion of his 80th birthday

The results of experiments where Tl⁺ and Pb²⁺ ions are electrolysed into a sodium borate glass (35 mol% Na₂O and 50 °C) are brought up to date in order to take into account recent developments in the chemistry of borate glasses. It is first necessary to consider the unique chemistry of the oxide(-II) species in terms of its electronegativity, electronic polarisability and acid–base properties, and the significant relationship between these is discussed. It is described how the Lewis basicity of oxidic materials such as glasses can be expressed quantitatively on the optical basicity scale and how determinations are made by various experimental methods. These methods include optical spectroscopy of ‘probe’ ions such as Tl⁺ or Pb²⁺, measurement of electronic polarisability and far-infrared spectroscopic ‘rattling’ frequencies of constituent metal ions. When Pb²⁺ ions are electrolysed into the sodium borate glass, it is found that there is migration of Na⁺ ions away from and of O²⁻ ions towards the (lead) anode with formation of PbO. There is almost complete depletion of Na₂O in the anode region so that the composition of the glass approximates to B₂O₃. A similar process occurs to a limited degree in the case of thallium, but the Tl⁺ ions are able to penetrate more deeply into the glass. Their ultraviolet ¹S₀ → ³P₁ frequency indicates that the sites they occupy have much greater basicity than the bulk glass. The two-site model of Kamitsos proposes that in borate glasses, there are higher and lower basicity sites, and the measured optical basicity of Tl⁺ indicates occupation of the higher sites. Since it has been shown that BO₄ groups in the glass are weakly basic, it is unlikely that they are involved in the higher sites. It is discussed how the higher site basicity implies greater covalency in the interaction of the Tl⁺ ion with the oxide(-II)s that constitute the pathway, and it is suggested that this is an important factor in the electromigration process.     

Syntheses and crystal structures of two new hydrated borates, Zn8[(BO3)3O2(OH)3] and Pb[B5O8(OH)]·1.5H2O

Two new hydrated borates, Zn₈[(BO₃)₃O₂(OH)₃] and Pb[B₅O₈(OH)]·1.5H₂O, have been prepared by hydrothermal reactions at 170 °C. Single-crystal X-ray structural analyses showed that Zn₈[(BO₃)₃O₂(OH)₃] crystallizes in a non-centrosymmetric space group R32 with a=8.006(2) Å, c=17.751(2) Å, Z=3 and Pb[B₅O₈(OH)]·1.5H₂O in a triclinic space group P1¯ with a=6.656(2) Å, b=6.714(2) Å, c=10.701(2) Å, α=99.07(2)°, β=93.67(2)°, γ=118.87(1)°, Z=2. Zn₈[(BO₃)₃O₂(OH)₃] represents a new structure type in which Zn-centered tetrahedra are connected via common vertices leading to helical ribbons _∞¹[Zn₈O₁₅(OH)₃]¹⁷⁻ that pack side by side and are further condensed through sharing oxygen atoms to form a three-dimensional _∞³[Zn₈O₁₁(OH)₃]⁹⁻ framework. The boron atoms are incorporated into the channels in the framework to complete the final structure. Pb[B₅O₈(OH)]·1.5H₂O is a layered compound containing double ring [B₅O₈(OH)]²⁻ building units that share exocyclic oxygen atoms to form a two-dimensional layer. Symmetry-center-related layers are stacked along the c-axis and held together by interlayer Pb²⁺ ions and water molecules via electrostatic and hydrogen bonding interactions. The IR spectra further confirmed the existence of both triangular BO₃ and OH groups in Zn₈[(BO₃)₃O₂(OH)₃], and BO₃, BO₄, OH groups as well as guest water molecules in Pb[B₅O₈(OH)]·1.5H₂O.     

Benzylammonium,imidazolium and pyridinium polyvanadates — Synthesis and characterization

Summary From the reaction systems,B-V₂O₅-HClO₄-H₂O andB-V₂O₅-H₂O, whereB is benzylamine (Bz), imidazole (Im) or pyridine (Py), eight new compounds were synthesized: at 20°C, the metavanadate and decavanadates of composition (BzH)VO₃, (BzH)₆V₁₀O₂₈·3H₂O, (ImH)₆V₁₀O₂₈·2H₂O, (PyH)₆V₁₀O₂₈·2H₂O, (ImH)₄H₂V₁₀O₂₈·2H₂O and (PyH)₄H₂V₁₀O₂₈·3H₂O, and at 60°C, the hexavanadates of composition (ImH)₂V₆O₁₆·H₂O and (PyH)₂V₆O₁₆·H₂O. ThepH ranges of solutions the polyvanadates can be isolated from, were estimated. The compounds prepared were characterized by chemical analysis and IR spectroscopy. The synthesis of deuterated analogues allowed to assign the IR bands corresponding to vibrations of water in the spectra of deca- and dihydrogendecavanadates and to V-OH vibrations in the spectra of dihydrogendecavanadates.

---

Benzylammonium-, Imidazolium- und Pyridinium-Polyvanadate. Synthese und Charakterisierung

Zusammenfassung Aus dem ReaktionssystemB-V₂O₅-HClO₄-H₂O undB-V₂O₅-H₂O [B=Benzylamin (Bz), Imidazol (Im) oder Pyridin (Py)] wurden acht neue Verbindungen synthetisiert: bei 20°C entstanden die Metavanadate und Decavanadate der Zusammensetzung (BzH)VO₃, (BzH)₆V₁₀O₂₈·3H₂O, (ImH)₆V₁₀O₂₈·2H₂O, (PyH)₆V₁₀O₂₈·2H₂O, (ImH)₄H₂V₁₀O₂₈·2H₂O und (PyH)₄H₂V₁₀O₂₈·3H₂O, bei 60°C entstanden die Hexavanadate (ImH)₂V₆O₁₆·H₂O und (PyH)₂V₆O₁₆·H₂O. DiepH-Bereiche, innerhalb derer Polyvanadate isoliert werden können, wurden abgeschätzt. Die Verbindungen wurden mittels chemischer Analyse und IR-Spektroskopie charakterisiert, wobei die Synthese deuterierter Analoga die Zuordnung von Banden unterstützte.