Präparation,Kristallstruktur, Schwingungsspektren und thermische Analyse von Kupfer‐tetrahydrogen‐decaoxo‐diperiodat‐hexahydrat CuH4I2O10·6H2O

On Copper‐tetrahydrogen‐decaoxo‐diperiodate‐hexahydrate CuH₄I₂O₁₀·6H₂O: Crystal Structure, Vibrational Spectroscopy and Thermal Analysis By crystallization from a strongly acidic aqueous solution copper‐tetrahydrogen‐decaoxodiperiodate‐hexahydrate CuH₄I₂O₁₀· 6H₂O has been obtained. In the structure of this compound (S.G. P 2₁/c, Nr.14), Z = 2, a = 1060.2(2) pm, b = 551.1(1) pm, c = 1164.7(2) pm, β = 111, 49(3)°) centrosymmetric [H₄I₂O₁₀]^2— anions in the form of two edge sharing octahedra form layers via hydrogen bonds originating from the acidic, trans‐configurated OH groups of the anions. Raman spectra are given and analyzed with respect to the internal vibrations of the periodate anion. The dehydration of the compound takes place via CuH₄I₂O₁₀·3H₂O and Cu(H₂IO₅)₂ which decomposes at 170 °C to Cu(IO₃)₂.     

Li2H4I2O10, das erste Tetrahydrogendimesoperiodat

Li₂H₄I₂O₁₀, the First Tetrahydrogendimesoperiodate Li₂H₄I₂O₁₀ has been obtained as an intermediate during the dehydration of LiH₄IO₆ · H₂O to LiIO₄, for the first time. According to the results of an X-ray structure determination (monoclinic, P2₁/n, a = 533.98(4), b = 471.85(4), c = 1431.48(10) pm, β = 91.614(7)°, Z = 2, 726 diffractometer data, R = 0.056), Li₂H₄I₂O₁₀ contains the previously unknown tetrahydrogendimesoperiodate ion H₄I₂O₁₀^2?, consisting of two edge-shared IO₆ octahedra. They are connected with LiO₆ octahedra via common edges and vertices. The crystals are non-merohedrally twinned along (100).     

Bi2(IO3)(IO6): First combination of [IO3]− and [IO6]5− anions in three-dimensional framework

A new bismuth (III) iodate periodate, Bi₂(IO₃)(IO₆) was obtained from hydrothermal reactions using Bi(NO₃)₃·5H₂O, and H₅IO₆ as starting materials. Bi₂(IO₃)(IO₆) crystallizes in the monoclinic space group P2₁/c (No. 14) with lattice parameters ɑ = 8.1119(6), b = 5.4746(4), c = 16.357(1) Å, β = 99.187(2)°, V = 717.07(9) ų, Z = 4. The structure of Bi₂(IO₃)(IO₆) features a three-dimensional framework which is a combination of [Bi(1)O₅] tetragonal pyramids, [Bi(2)O₈] bicapped trigonal prisms and [IO₃]⁻ and [IO₆]⁵⁻ anions. Thermal analysis shows that the compound is thermally stable up to about 350 °C. The solid state UV-vis-NIR diffuse reflectance spectrum indicates that Bi₂(IO₃)(IO₆) is a semiconductor with a band gap of 2.76 eV.     

Neue Quecksilber(II)-perjodate

New Mercury(II) Periodates From Hg(NO₃)₂ and H₅IO₆ soluted in nitric acid of variated concentration, the long known Hg₅(IO₆)₂ and the new salts Hg₂HIO₆ (brown), Hg₃(H₂IO₆)₂ (yellow), Hg₃(IO₅)₂ (black), and HgH₃IO₆ (colourless) have been prepared. Dehydration of HgH₃IO₆ leads to the brown salt HgHIO₅. The structure of the new compounds has been deduced from their i.r. spectra. The existence of the earlier reported salts Hg(IO₄)₂, Hg₄I₂O₁₁, Hg₇(IO₇)₂ · 18 H₂O and Hg₆I₂O₁₃ · 20 H₂O has not been confirmed.     

Hexahydroxojod(VII)-Salze

Hexahydroxoiodine(VII) Salts. H₅IO₆ reacts with concentrated H₂SO₄ and concentrated H₂SeO₄ forming the compounds H₅IO₆ · H₂SO₄ and H₅IO₆ · H₂SeO₄, respectively. As shown by their RAMAN spectra, these compounds are salts [I(OH) ₆]HSO₄ and [I(OH) ₆]HSeO₄ containing the hexahydroxoiodine(VII) cation [I(OH) ₆]⁺· Under particular conditions furthermore [I(OH) ₆]₂SO₄ has been obtained.     

Zur Kenntnis der Perjodsäuren HJO4 und H7J3O14: Neue Darstellung,Ramanspektren und Struktur

On the Periodic Acids HIO₄ and H₇I₃O₁₄: Novel Preparation, Raman Spectra, and Structure HIO₄ and H₇I₃O₁₄ have been prepared from H₅IO₆ by dehydration with 100 and 97 p.c. H₂SO₄, respectively. These substances are identical with those obtained from H₅IO₆ by thermal dehydration. From their Raman spectra it is concluded that the iodine atoms in the compounds are octahedrally coordinated with oxygen atoms. According to this coordination, HIO₄ is polymeric. For both compounds structural formulae are suggested.     

Über die Existenz Polymerer Jodylionen (JO2+)x in den Verbindungen J2O5· n SO3 (n = 1,2,3) und JO2SO3F

On the Existence of Polymeric Iodyl Ions (IO₂⁺)_x in the Compounds I₂O₅ · n SO₃ (n = 1, 2, 3) and IO₂SO₃F The Raman spectra of I₂O₅ · SO₃, I₂O₅ · 2 SO₃ and I₂O₅ · 3 SO₃ are reported and interpreted together with the known spectrum of IO₂SO₃F. In first approximation the structure of the compounds is described by the existence of polymeric iodyl ions (IO₂⁺)_x. The bonds between cation and anion are not purely ionic but are in part covalent. These are formulated as coordinative bonds.     

REI5O14 (RE=Y and Gd): Promising SHG Materials Featuring the Semicircle‐Shaped I5O143− Polyiodate Anion

The first examples of rare‐earth polyiodates, namely, REI₅O₁₄ (RE=Y and Gd), have been prepared by hydrothermal reactions of RE₂O₃ and H₅IO₆ in H₃PO₄ (≥85 wt % in H₂O), with extremely high yields (>95 %). They crystalize in the polar space group Cm and feature a brand‐new semicircle‐shaped [I₅O₁₄]^3? pentameric polyiodate anion composed of two IO₃ and three IO₄ polyhedra. Remarkably, both compounds exhibit very large second‐harmonic generation (SHG) signals (14× and 15×KH₂PO₄ (KDP) upon 1064 nm laser radiation for Y and Gd compounds, respectively). Our work shows that the hydrothermal reaction in a phosphoric acid medium facilitates the formation of rare‐earth polyiodates.     

Study of some phenolic-iodine redox polymeric products by thermal analyses and mass spectrometry

Summary This paper describes the use of the mass spectrometry (MS), thermal analyses (TA) and other physico-chemical methods to investigate the structure of two newly synthesized phenolic-iodine derivative polymeric products. These two products are formed as a result of redox-interaction of adrenaline hydrogen tartrate (AHT, I) with iodate (IO^-₃) and periodate (IO^-₄). The characterization of the two products were achieved satisfactorily by using the above tools and their proposed general formulae, were found to be C₅₂H₆₇O₃₆N₄I (AHT- IO^-₃, II) and C₂₆H₃₄O₁₈N₂I₂(AHT- IO^-₄, III). The fragmentation behavior of the main compound (AHT) in MS and TA (TG and DTA) techniques was investigated and compared. The results obtained were used to explain the fragmentation of the products AHT- IO^-₃and AHT- IO^-₄in mass spectrometry and thermal analyses techniques. The stabilities of different fragments were discussed. The results indicate that the two techniques are supporting each other in which the mass spectrometry provides the structural information in gas phase while the thermal analyses provides the quantitative fragmentation in the solid-state.     

The first transition metal iodato peroxido complex: the synthesis, vibrational spectra and crystal structure from powder diffraction data of K3[V2O2(O2)4(IO3)]·H2O

The first transition metal iodato peroxido complex, K₃[V₂O₂(O₂)₄(IO₃)]·H₂O (I), was prepared by crystallization from the KVO₃ — KIO₃ — H₂O₂ — H₂O — ethanol (HNO₃) solution. The dinuclear anion is immediately decomposed in aqueous solution; the ⁵¹V NMR spectrum exhibits signals corresponding to [VO(O₂)₂(H₂O)]^?, [V₂O₂(OH)(O₂)₄]^3? and H₂VO₄ ^? species only. The IR and Raman spectra contain all characteristic bands of the VO(O₂)₂ group and the coordinated IO₃ ^? ligand. Based on the positions of bands assigned to the vibrations of the VO(O₂)₂ groups a pentagonal pyramidal arrangement around the vanadium atoms can be supposed. The crystal structure was solved from X-ray synchrotron powder data by direct space method and refined by energy minimization in the solid state employing a hybrid PBE0 functional. This crystal and molecular structure, has confirmed the presence of hexacoordinated vanadium atoms and revealed asymmetric dinuclear structure of the [V₂O₂(O₂)₄(IO₃)]^3? ion. The coordination spheres of vanadium atoms are different — the IO₃ ^? anion is coordinated only to one vanadium center. A thermal analysis of the complex confirmed the presence of water molecules in the crystal structure and revealed a considerable stability of the dehydrated complex.      

Zur Kenntnis von Na5HI2O10 · 14 H2O

On Na₅HI₂O₁₀ · 14 H₂O Single crystals of Na₅HI₂O₁₀ · 14 H₂O were obtained for the first time. According to the results of an X-ray crystal structure determination (P1 , a = 8.450(7), b = 8.533(6), c = 9.066(6) Å, α = 76.96(6), β = 62.94(5), γ = 86.98(6°, Z = 1, 4970 diffractometer data) iodine is in a distorted octahedral coordination. Two IO₆ polyhedra are connected by a common edge forming dimeric anions H₂I₂O₁₀^4?, the site symmetry is 1 . Sodium exhibits C.N. 6 (mainly hydrate). A 3-d network is formed largely by H-bonds.     

Thermolysis of disubstituted lithium and sodium orthoperiodates

Na₂H₃IO₆ decomposes with water and oxygen evolution in the range of 180–250°C under the atmospheric pressure or in a dynamic vacuum. The solid residue is an equimolar mixture of NaIO₃ and Na₃IO₅. Na₃IO₅ likely occurs in the form of the dimer Na₆I₂O₁₀. An intermediate thermolysis stage is the elimination of a water molecule from the salt molecule with simultaneous disproportionation of the salt to trisubstituted orthoperiodate and metaperiodate: Na₂H₃IO₆ = 0.5Na₃H₂IO₆ + 0.5NaIO₄ + H₂O. Li₂H₃IO₆ thermolysis under the atmospheric pressure proceeds in the same way; however in vacuum, the thermolysis yields LiIO₃ and Li₅IO₆ in the ratio of 3: 1 (mol/mol). The reason for the different thermolysis routes lies in the different stability of the intermediates M₃H₂IO₆ and MIO₄.     

Kristallstruktur,Infrarot‐ und Ramanspektren von Kupfertrihydrogenperiodatmonohydrat,CuH3IO6 · H2O

Crystal Structure, Infrared and Raman Spectra of Copper Trihydrogenperiodate Monohydrate, CuH₃IO₆ · H₂O The hitherto unknown compound CuH₃IO₆ · H₂O was studied by X‐ray, IR‐ and Raman spectroscopic methods. The crystal structure was determined by X‐ray single‐crystal studies (space group P2₁2₁2₁, Z = 4, a = 532.60(10), b = 624.00(10), c = 1570.8(3) pm, R1 = 1.85%, 1559 unique reflections (I > 2σ(I))). Isolated, meridionally configurated H₃IO₆^2– ions are coordinated to the copper ions forming double‐ropes in [100]. These ropes are connected in [010] and [001] by hydrogen bonds. The copper ions possess a square pyramidal co‐ordination with the hydrate H₂O on top. The infrared and Raman spectra as well as group theoretical treatment are presented and discussed with respect to the strength of the hydrogen bonds and the co‐ordination of the CuO₅₍₊₁₎ polyhedra and the H₃IO₆^2– ions at the C₁ lattice sites. The hydrogen bonds of the H₂O molecules and H₃IO₆^2– ions (HO–H…O–IO₅H₃ and H₂IO₅O–H…O–IO₅H₃) greatly differ in strength, as shown from both the respective O…O distances: 282.6 and 298.6 pm (H₂O), and 258.8, 259.7, and 270.9 pm (H₃IO₆^2–) and the OD stretching modes of isotopically dilute samples: 2498 and 2564 cm^–1 (90 K) (HDO), and 1786, 2024, and 2188 cm^–1 (H₂DIO₆^2–). The IO stretching modes of the H₃IO₆^2– ions (696–788 cm^–1 and 555–658 cm^–1, 295 K) display the different strength of the respective I–O and I–O(H) bonds (r_I–O: 181.1–188.3 pm and 189.2–194.5 pm).     

Crystal Structure and Properties of Rb4H2I2O10 · 4H2O

Single crystals of the Rb₄H₂I₂O₁₀· 4H₂O were synthesized for the first time and studied by X-ray diffraction analysis. The crystals are monoclinic, a = 7.321(6) Å, b = 12.599(8) Å, c = 8.198(8) Å, = 96.30(7)°, Z = 2, space group P2₁/c. The H₂I₂O₁₀ ^4– anion is formed by the edge-sharing IO₆ octahedra. The anions are united by hydrogen bonds into a chain running along the x axis. The chains are combined by water molecules into a three-dimensional structure through hydrogen bonds. The compound is a proton conductor. The conductivity values measured at 20–60°C vary within 10^–6 to 10^–4 ohm^–1 cm^–1.     

Synthesis and Structure of Ln2(H4IO6)(I2O10)·H3O·5 H2O (Ln=Pr,Nd, Sm), a Lanthanide Periodate Diperiodate

By slow evaporation of solutions containing Ln(ClO₄)₃ (Ln=Pr, Nd, Sm), H₅IO₆ and an excess of HClO₄, crystals of the title compounds could be obtained. Their structures were determined by single‐crystal X‐ray diffraction. The compounds crystallize in the monoclinic crystal system, space group I2/a. They contain two types of periodate ions: octahedral H₄IO₆ groups and two crystallographically different I₂O₁₀ groups, which consist of two edge‐sharing octahedra. These anions coordinate to the cations as bridging groups yielding a three‐dimensional network. Together with some water of crystallization, a coordination number of 9 is achieved around the lanthanide ions with a tri‐capped trigonal prismatic geometry.     

IR- und Raman-Spektren der isotypen Iodathydrate M(IO3)2 · 4 H2O (M = Mg,Ni, Co); Kristallstruktur von Co(IO3)2 · 4 H2O

Infrared and Raman Spectroscopy of the Isostructural Iodate Hydrates M(IO₃)₂ · 4 H₂O (M = Mg, Ni, Co)-Crystal Structure of Cobalt Iodate Tetrahydrate The iodate tetrahydrates Mg(IO₃)₂ · 4 H₂O, β-Ni(IO₃)₂ · 4 H₂O, Co(IO₃)₂ · 4 H₂O and their deuterated specimens were studied by X-ray, infrared and Raman spectroscopic methods. The title compounds are isostructural crystallising in the monoclinic space group P2₁/c (Z = 2). The crystal structure of Co(IO₃)₂ · 4 H₂O (a = 836.8(5), b = 656.2(3), c = 850.2(5) pm and β = 100.12(5)°) has been refined by single-crystal X-ray methods (R_obs = 3.08%, 693 unique reflections I₀ > 2σ(I)). Isolated Co(IO₃)₂(H₂O)₄ octahedra form layers parallel (100). Within these layers, the two crystallographically different hydrate water molecules form nearly linear hydrogen bonds to adjacent IO₃^– ions (ν_OD of matrix isolated HDO of Co(IO₃)₂ · 4 H₂O (isotopically diluted samples) 2443 (H3), 2430 (H2), and 2379 cm^–1 (H1 and H4), –180 °C). Intramolecular O–H and intermolecular H…O distances were derived from the novel ν_OD vs. r_OH and the traditional ν_OD vs. r_H…O correlation curves, respectively. The internal modes of the iodate ions of the title compounds are discussed with respect to their coupling with the librations of the hydrate H₂O molecules, the distortion of the IO₃^– ions, and the influence of the lattice potential.     

Ag9I3(SeO4)2(IO3)2 – Synthesis,Crystal Structure,and Ionic Conductivity

Ag₉I₃(SeO₄)₂(IO₃)₂ was obtained for the first time by reacting a stoichiometric mixture of Ag₂O, AgI and SeO₂ at elevated oxygen pressure (255 MPa) and at a temperature of 500 °C. Ag₉I₃(SeO₄)₂(IO₃)₂ was characterized by X‐ray powder diffraction, differential scanning calorimetry, impedance spectroscopy and single crystal structure analysis. The crystal structure was solved by direct methods (I23, Z = 8, a = 12.9584(6) Å, V = 2175.9(2) ų and R₁ = 2.70 %). The crystal structure consists of isolated SeO₄ tetrahedra and trigonal IO₃ pyramids separated by Ag⁺ and I^– ions. Each four of the SeO₄^2– and IO₃^– anions aggregate, forming a novel supramolecular building block, showing a hetero‐cubane like structure. According to the results of impedance measurements, Ag₉I₃(SeO₄)₂(IO₃)₂ is a good silver ion conductor. The compound shows an abrupt increase in the ionic conductivity in the temperature range of 115 to 147 °C, and has a silver ion conductivity of 7.1 × 10^–5 Ω^–1 cm^–1 at 25 °C. The activation energy for silver ion conduction is 0.45 eV, in the temperature range from 25 to 115°.     

New thallium iodates—Synthesis, characterization, and calculations of Tl(IO3)3 and Tl4(IO3)6, [Tl3Tl(IO3)6]

Two new thallium iodates have been synthesized, Tl(IO₃)₃ and Tl₄(IO₃)₆ [Tl⁺₃Tl³⁺(IO₃)₆], and characterized by single-crystal X-ray diffraction. Both materials were synthesized as phase-pure compounds through hydrothermal techniques using Tl₂CO₃ and HIO₃ as reagents. The materials crystallize in space groups R-3 (Tl(IO₃)₃) and P-1 (Tl₄(IO₃)₆). Although lone-pairs are observed for both I⁵⁺ and Tl⁺, electronic structure calculations indicate the lone-pair on I⁵⁺ is stereo-active, whereas the lone-pair on Tl⁺ is inert.     

Complexing between orthoperiodic acid and periodate ion in nitric acid solutions

Preparative synthesis techniques have been developed for four complex salts (Rb[H₄IO₆ · H₅IO₆], Cs[H₄IO₆ · H₅IO₆], Cs[H₄IO₆ · H₅IO₆ · 0.5H₂O], and 2CsNO₃ · HNO₃ · H₅IO₆). In the Cs(Rb)NO₃-H₅IO₆-HNO₃-H₂O systems, the starting component ratios, temperature schedules, and solvent-evaporation (H₂O + HNO₃) parameters have been determined to ensure the crystallization of the said compounds in individual states. For complex 2CsNO₃ · HNO₃ · H₅IO₆, solid-phase synthesis has also been developed. Highly water-sensitive Cs[H₄IO₆ · H₅IO₆] in the presence of water vapor converts to Cs[H₄IO₆ · H₅IO₆ · 0.5H₂O].