Structural, Thermal behaviour and Vibrational study of a new Cesium- Ammonium Dihydrogen Phosphate Arsenate: Cs0.55(NH4)0.45H2(PO4)0.39(AsO4)0.61

Mixed crystals Cs0.55(NH4)0.45H2(PO4)0.39(AsO4)0.61 (CADPA) of the two antiferroelectric NH4H2PO4 (ADP) and NH4H2AsO4 (ADA) and of the two ferroelectric CsH2PO4 (CDP) and CsH2AsO4 (CDA) have been prepared by slow evaporation from aqueous solution at room temperature. The structural properties of the crystal were characterized by X-ray single analysis (performed at room temperature), which revealed that (CADPA) crystallizes in space group I42d with lattice parameters: a = 7.6473(1) Å, c = 7.6803(1) Å and Z = 4. The title compound is isostructural with the tetragonal phases of (ADP) and (ADA). This structure is characterized by two kinds of disorder: a statical or dynamical disorder of the acidic proton in the O–H…O hydrogen bond and another one which is connected with a reorientational motion of NH4+ ions. Broader peaks in the IR spectrum confirm a structural disorder in this material. Thermal analysis of the (CADPA) were characterized by differential scanning calorimetry (DSC), showed that the title compound undergo two phase transitions at T = 204 K and T = 407 K

A new Rubidium - Bismuth polyphosphate RbBi(PO3)4: Growth, X-ray single crystal and vibrational study

Solid-solution studies in the ternary Rb2O – Bi2O3 – P2O5 system, carried out in a search for inorganic materials have a considerable interest mainly for their optical properties, specifically in laser technology, yielded the new compound RbBi(PO3)4. Single-crystal X-ray measurement revealed that RbBi(PO3)4 crystallizes in space group P21/c with a structural type IV and has lattice parameters a = 10.430, b = 8.984, c = 12.967 Ã…, ï¢ = 126.1°, Z = 4 and V = 981.6 Ã…3. The all eighteen atoms were located in the asymmetric unit. Refinement using anisotropic temperature factors for all atoms yielded weighted residuals based on F and F2 values, respectively, of R1 = 0.0131 and WR2 = 0.0252 for all observed reflections. The atomic arrangement can be described as a long chain polyphosphate organization, helical ribbons (PO3)n. Two types of infinite chains, with a period of eight PO4 tetrahedra run along the longest unit-cell directions. Infrared and Raman spectra at room temperature, were investigated, show clearly some characteristics bands of infinite chains structure of PO4 tetrahedra linked by a bridge oxygen

THERMAL AND ELECTRICAL BEHAVIOUR OF THE SUPERPROTONIC CONDUCTOR PHASE IN Rb2(HSeO4)1.5(H2AsO4)0.5

Crystals of a new compound with a superprotonic phase transition Rb2(HSeO4)1.5(H2AsO4)0.5 (noted RbHSeAs), were synthesized by slow evaporation of an aqueous solution at room temperature. The differential scanning calorimetric analyses showed two endothermic peaks at 465 K and 566 K. The last peak corresponds to the decomposition of the material. The first transition was characterized by several techniques (impedance spectroscopy, complex modulus, Raman and X-ray diffraction powder depending on temperature). ac impedance measurements revealed that, upon heating, the compound undergoes at ~ 443 K a sharp increase in conductivity from a low temperature protonic phase to a superprotonic conductivity phase. The activation energies calculated from the modulus (ï„Ef) and impedance (ï„Eï³) spectra respectively are approximately equal, suggesting that the transport properties in this material above and below the superprotonic phase transition (443 K) are probably due to an H+ protons hopping mechanism

Crystal structure, thermal behavior and spectroscopic studies of a new organic hydrogen arsenate

The present paper undertakes the study of a title organic-inorganic hybrid material 2-amino-3-benzyloxy pyridinium dihydrogenmonoarsenate, [C12H13N2O]H2AsO4, which has been synthesized by slow evaporation at room temperature using 2-amino-3-benzyloxypyridine as the structure-directing agent. The structure was determined by single-crystal X-ray diffraction at 296 K. This compound is crystallized in the noncentrosymmetric orthorhombic space group P212121 with the lattice parameters a = 4.89 (7), b = 10.41 (1), c = 26.79 (3) Ã…, V = 1364.3 (3) Ã…3, and Z = 4. The crystal structure has been determined and refined to R1 = 0.0363 and wR2 = 0.1246 using 5438 independent reflections. The atomic arrangement can be described by infinite anionic chains running parallel to the [100] direction. The organic entities are located between these chains. H-bonds connecting the different species play an important role in the one-dimensional network cohesion. This compound is also characterized by solid-state 13C MAS NMR, IR, Raman spectroscopy and TG-ATD thermal analysis. Moreover, protonic conduction of this compound determined by impedance has been studied in the temperature range 299 - 403 K

Ethyl­enediammonium tetraaquadi­sulfatomagnesium(II)

The title compound, [NH3(CH2)2NH3][Mg(SO4)2(H2O)4], was synthesized by the slow evaporation method. Its crystal structure can be described as an alternate stacking of inorganic layers of tetra­aqua­bis(sulfato-O)magnesium [Mg(SO4)2(H2O)4]2− anions ( symmetry) and organic layers of [NH3(CH2)2NH3]2+ cations along the crystallographic b axis. The anions, built up from tetrahedral SO4 units and octahedral Mg(H2O)4O2 units, and the cations are linked together through N—H⋯O hydrogen bonds, forming a three-dimensional network. O—H⋯O inter­actions are also present

Synthesis, Crystal Structure and Characterization of [(CH3 CH2)4N] Mn1,5 Cl3 4H2O Cl 2(H2O)

Single crystals of [(CH3CH2)4N] Mn1,5 Cl3 4H2O Cl 2(H2O) were grown by the slow evaporation technique and characterized by means of single-crystal X-ray diffraction, FT-IR and Raman spectroscopy. The title compound belongs to the triclinic space group P with the following unit cell dimensions: a =7.5425(4) Å, b=9.8464 Å, c=13.7671(6) Å, α=89.951(3)°,β=89.753(3)°, γ=81.861(3)°, Z=4. These structures have solved using direct methods and refined by least-squares analysis. The structure was solved by the direct method and refined to final R value of 0.0567. The projection of [(CH3CH2)4N] Mn1,5 Cl3 4H2O Cl 2(H2O) in the plan (a,b) shows an arrangement in layers perpendicular to the direction b . The structure consists of infinite parallel two-dimensional planes built connected ions and water molecules by strong O-H…O and O-H…Cl hydrogen bonding

Crystal structure, thermal behavior and vibrational studies of tetraethylammonium dihydrogenarsenate bis-arsenic acid [(C2H5)4N].[H2AsO4].[H3AsO4]2

An organic-inorganic hybrid compound of tetraethylammonium dihydrogenarsenate bis-arsenic acid salts of formula [(CH3CH2)4N].[H2AsO4].[H3AsO4]2(TEAs) were grown by the slow evaporation and characterized by means of single crystal X-ray diffraction, thermal analysis, FT-IR and Raman spectroscopy. This compound crystallize in the space groups Cc with unit cell parameters, a= 20.105(2) Å; b= 7.342(4) Å, c = 15.292(2) Å, γ = 115(4)°, Z = 4, R= 0.07. The structure has solved using direct methods and refined by least-squares analysis. In this case, the structure consists of infinite parallel two-dimensional planes built of mutually H2AsO4−, H3AsO4 tetrahedra connected by strong O-H···O hydrogen bonding. The thermoanalytical properties were studied using TG of TEAs method in the temperature ranges from 300 to 440 K for this hygroscopic sample. DSC measurement was carried out in the temperature range from 305 to 425 K

Crystal structure and spectroscopic study of bis-tetrapropylammonium hexachlorodicuprate(II), [N(C3H7)4]2Cu2Cl6

Single crystals of the bis-tetrapropylammonium hexachlorodicuprate(II), [N(C3H7)4]2Cu2Cl6, were grown by slow evaporation solution technique at room temperature. The compound was characterized by Raman, IR and single crystal X-ray diffraction studies. Crystal data for C12H28Cl3CuN (M = 356.24 g/mol): triclinic, space group P-1 (no. 2), a = 9.3851(2) Å, b = 9.3844(2) Å, c = 11.8837(3) Å, α = 106.3330(11)°, β = 100.0280(12)°, γ = 113.2830(12)°, V = 872.95(3) Å3, Z = 2, T = 293(2) K, μ(MoKα) = 1.693 mm-1, Dcalc = 1.355 g/mm3, 8056 reflections measured (6.64 ≤ 2Θ ≤ 62.02), 5526 unique (Rint = 0.0303) which were used in all calculations. The final R1 was 0.0427 (>2σ(I)) and wR2 was 0.1312 (all data). The atomic arrangement can be described by alternating organic and inorganic layers parallel to the (101) plan, made up of tetrapropylammonium groups and Cu2Cl6 dimers, respectively. In crystal structure, the inorganic layers, built up by Cu2Cl6 dimers, are connected to the organic ones through hydrogen bonding C-H…Cl and Van der Waals interaction in order to build cation-anion-cation cohesion. These interactions cause to the formation of a three-dimensional supramolecular architecture

Crystal structures and characterization of two divalent metal selenates templated by dabco, (C6H14N2)[MII(H2O)6](SeO4)2 (MII: NiII, ZnII)

International audienceTwo new organic-inorganic hybrid materials have been synthesized and crystallographically characterized. Both compounds, (C6H14N2)[Ni(H2O)6](SeO4)2 (I) and (C6H14N2)[Zn(H2O)6](SeO4)2 (II), crystallize isotypically in the monoclinic system, space group P21/c, with the following unit cell parameters: a = 12.4045(3), b = 11.9360(3), c = 12.8366(3) Å, β = 108.518(2)°, V = 1802.18(8) Å3, Z = 4 for compound (I) and a = 12.7839(2), b = 11.9153(4), c = 12.3814(2) Å, β = 108.264(5)°, V = 1790.97(7) Å3, Z = 4 for the zinc related phase. Their supramolecular structure consists of metallic cation octahedrally coordinated by six water molecules [MII(H2O)6]2+, selenate anions (SeO4)2- and dabcodiium cation (C6H14N2)2+ linked together via two types of hydrogen bonds, Ow-H...O and N-H...O only. The thermal decomposition of these supramolecular compounds takes place in several steps leading to the formation of metal oxide. The magnetic measurements show that the nickel based compound is predominantly paramagnetic with weak antiferromagnetic interactions at low temperature