Crystal structure and phase transition in the compound [C6H17N3]TlCl5.2H2O

The title compound 1-(2-ammonium-ethyl) piperaziniumpentachlorothallate (III) dihydrate crystallizes in the monoclinic system with space group Cm. The unit cell dimensions are: a = 12.786(5), b = 12.021(5), c = 10.566(5) Ã…, β = 93.469(5) °, with Z = 4. Its crystal structure was determined and refined down to R = 0.045. The structure of this compound consists of 1-(2-ammonium-éthyl) pipéraziniumcations and [Tl2Cl10]4- dimers. The arylammoniumcations are located between anions and connected to the halogen atoms by N-H…Cl hydrogen bonds. One phase transition at T = 320 K is detected and studied by differential scanning calorimetry, dielectric and impedance spectroscopy measurements. The evolution of the dielectric constant and dissipation factor as a function of temperature revealed the transition characterized by a strong jump in the conductivity plot.Â

Synthesis, Crystal Structure and Vibrational Properties of bis (N-benzylmethylammonium) Pentachlorobismuthate (III)

The [C8H12N]2 BiCl5 compound crystallised in the triclinic system with space group  P-1  with a = 9,833(4),                     b = 10,044(7), c = 12,225(7) Ã…, a= 78.82(4), β = 75,42(4), g= 76.89°(5)  and Z = 2. The average density value, Ïx = 1.518 g.cm-3  is in agreement with the calculated one, Ïx = 1.494 g.cm-3. The atomic arrangement can be described as an alternation of organic and inorganic layers. The anionic layer is built up of octahedral [Bi2Cl10]-4. The organic layers are arranged in sandwich between the anionic ones. The crystal packing is governed by means of the ionic N–H---Cl hydrogen bonds, forming a three dimensional network. The nature of the distortion of the inorganic polyhedra has been studied and can be attributed to the stereo activity of the Bi(III) lone electron pair. The infrared and Raman spectra was recorded in the 4000–400 cm-1 frequency region

Structural characterization, vibrational and optical properties of a novel one-dimensional organic-inorganic hybrid based-iodobismuthate(III) material, [C10H7NH3]BiI4

International audienceThe new organic-inorganic hybrid compound [C10H7NH3]BiI4 has been grown by the solvent evaporation method. The one-dimensional (1D) structure for [C10H7NH3]BiI4 has been determined by the single-crystal X-ray diffraction to be orthorhombic. Pbca with a = 15.515(3) angstrom, b = 7.643(2) angstrom. c = 29.067(5) angstrom and Z = 8. The structure consists of corrugated layers of BiI4- chains, with Bi-I bond lengths ranging from 2.9260(2) to 3.2659(2) angstrom, separated by the organic (C10H7NH3)(+) cations. The crystal packing is governed by I center dot center dot center dot I electrostatic interactions forming a self-assembled multiple pseudo-two-dimensional structure. Raman and infrared spectra were used to gain more information of the title compound. An assignment of the observed vibration modes is reported. The optical absorption for thin films of the one-dimensional hybrid has also been investigated, revealing a semiconductive behavior with a characteristic energy of E-g = 2.32 eV

Crystal structure, vibrational studies, optical properties and DFT calculations of 2-amino-5-diethyl-aminopentanium tetrachlorocadmate (II)

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Crystal structure and phase transition of the quinolinium tetrabromothallate(III)

International audienceThe salt quinolinium tetrabromothallate(III) is orthorhombic Pna2(1) with the following unit cell dimensions: a = 9.582(2), b = 10.0210(19), c = 14.916(2) angstrom, Z = 4. The structure was solved by Patterson methods and refined to a final R-value of 0.0452 for 2043 observed reflections. The examination of the structure shows quinolinium cations separating chains of tetrahedral TlBr4-, these chains are perpendicular to the c axis. Infrared spectra confirms the presence of the organic cations, differential scanning calorimetry reveals a transition at T = 406 K. Electrical measurements and X-ray powder diffraction were performed to discuss the mechanism of the phase transition

Crystal structure and investigation of phase transitions in hexa (2 amino-indolinium) dodecachlorobithallate(III) and quinolinium tetrachlorothallate(III)

International audienceTwo new thallium containing salts with different aryl ammonium cations have been prepared and characterized by X-ray crystallography, infrared spectroscopy and dielectric measurements. The salt [C8N2H8](6)Tl2Cl12 (1) crystallizes in the monoclinic system with space group Pn. The unit cell dimensions are: a = 15.120(5), b = 11.825(5), c = 17.167(5) angstrom, beta = 104.460(5)degrees with Z = 2, D-calcd = 1.818 g cm(-3), R = 0.0369. The structure consists of 2 amino-indo-linium cations and monomeric TICl63- anions. The TICl63- has a strongly octahedral geometry presenting five short and one long (T11-C113 = 2.739(5) and T12-C126 = 2.684(5) angstrom) Tl-Cl bonds. The presence of multiple hydrogen bonds is considered to be responsible for the octahedral distortion. However, the second compound [C9H8N]TlCl4 (2) crystallizes in the Pna2(1) orthorhombic space group, with a = 9.253(1), b = 9.799(1), c = 14.558(2) angstrom, Z = 4, D-calcd = 2.397 g cm(-3), R = 0.0608. The structure of the quinolinium tetrachlorothallate(III) is characterized by tetracoordinate thallium, forming a regular tetrahedral TlCl4 with Tl-Cl distances between 2.366(2) and 2.451(3) angstrom. The structure consists of quinolinium cations separating chains of TlCl4- tetrahedra, these chains being perpendicular to the c axis. Infrared spectra confirm the presence of the organic cations. Differential scanning calorimetry study was carried out. Electrical measurements were performed to discuss the mechanism of the phase transition