I. Chaabane

A theoretical study on the molecular structure and vibrational (FT-IR and Raman) spectra of new organic–inorganic compound [N(C3H7)4]2SnCl6

Tetrapropylammoniumchloride was used as a ligand for the synthesis of the new organic-inorganic compound bis-tetrapropylammoniumhexachlorostannate. Vibrational study in the solid state was performed by FT-IR of the free Tetrapropylammoniumchloride ligand (TPACL) and by FT-IR and FT-Raman spectroscopies of the [N(C3H7)4]2SnCl6 compound. The comparative analysis of the Infrared spectra of the title compound with that of the free ligand was discussed. The structure of the [N(C3H7)4]2SnCl6 compound was optimized by density functional theory (DFT) using B3LYP method and shows that the calculated values obtained by B3LYP/LanL2MB basis are in much better agreement with the experimental data than those obtained by B3LYP/LanL2DZ. The vibrational frequencies were evaluated using density functional theory (DFT) with the standard B3LYP/LanL2MB basis, and were scaled using various scale factors. Root mean square (RMS) value was calculated and the small difference between experimental and calculated modes has been interpreted by intermolecular interactions in the crystal.

Synthesis, Infra-red, Raman, NMR and structural characterization by X-ray Diffraction of [C12

The synthesis, infra-red, Raman and NMR spectra and crystal structure of 2, 4, 4-trimethyl-4, 5-dihydro-3H-benzo [b] [1, 4] diazepin-1-ium tetrachlorocadmate, [C12H17N2]2CdCl4 and benzene-1,2-diaminium decachlorotricadmate(II) [C6H10N2]2Cd3Cl10 are reported. The [C12H17N2]2CdCl4 compound crystallizes in the triclinic system (P1¯MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8bkY=wiFfYlOipiY=Hhbbf9v8qqaqFr0xc9vqpe0di9q8qqpG0dHiVcFbIOFHK8Feei0lXdar=Jb9qqFfeaYRXxe9vr0=vr0=LqpWqaaeaabiGaciaacaqabeaabeqacmaaaOqaaGqaaiab=bfaqnaanaaabaGaeGymaedaaaaa@2D26@ space group) with Z = 2 and the following unit cell dimensions: a = 9.6653(8) Å, b = 9.9081(9) Å, c = 15.3737(2) Å, α = 79.486(1)°, β = 88.610(8)° and γ = 77.550(7)°. The structure was solved by using 4439 independent reflections down to R value of 0.029. In crystal structure, the tetrachlorocadmiate anion is connected to two organic cations through N-H...Cl hydrogen bonds and van der Waals interaction as to build cation-anion-cation cohesion. The [C6H10N2]2Cd3Cl10 crystallizes in the triclinic system (P1¯MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8bkY=wiFfYlOipiY=Hhbbf9v8qqaqFr0xc9vqpe0di9q8qqpG0dHiVcFbIOFHK8Feei0lXdar=Jb9qqFfeaYRXxe9vr0=vr0=LqpWqaaeaabiGaciaacaqabeaabeqacmaaaOqaaGqaaiab=bfaqnaanaaabaGaeGymaedaaaaa@2D26@ space group). The unit cell dimensions are a = 6.826 (5)Å, b = 9.861 (7)Å, c = 10.344 (3)Å, α = 103.50 (1)°, β = 96.34 (4)° and γ = 109.45 (3)°, Z = 2. The final R value is 0.053 (Rw = 0.128). Its crystal structure consists of organic cations and polymeric chains of [Cd3 Cl10]4- anions running along the [011] direction, in the [C6H10N2]2Cd3Cl10 compounds hydrogen bond interactions between the inorganic chains and the organic cations, contribute to the crystal packing.PACS Codes: 61.10.Nz, 61.18.Fs, 78.30.-j

Synthesis, Infra-red, Raman, NMR and structural characterization by X-ray Diffraction of [C12H17N2]2CdCl4 and [C6H10N2]2Cd3Cl10 compounds

The synthesis, infra-red, Raman and NMR spectra and crystal structure of 2, 4, 4-trimethyl-4, 5-dihydro-3H-benzo [b] [1, 4] diazepin-1-ium tetrachlorocadmate, [C12H17N2]2CdCl4 and benzene-1,2-diaminium decachlorotricadmate(II) [C6H10N2]2Cd3Cl10 are reported. The [C12H17N2]2CdCl4 compound crystallizes in the triclinic system (P1¯MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8bkY=wiFfYlOipiY=Hhbbf9v8qqaqFr0xc9vqpe0di9q8qqpG0dHiVcFbIOFHK8Feei0lXdar=Jb9qqFfeaYRXxe9vr0=vr0=LqpWqaaeaabiGaciaacaqabeaabeqacmaaaOqaaGqaaiab=bfaqnaanaaabaGaeGymaedaaaaa@2D26@ space group) with Z = 2 and the following unit cell dimensions: a = 9.6653(8) Å, b = 9.9081(9) Å, c = 15.3737(2) Å, α = 79.486(1)°, β = 88.610(8)° and γ = 77.550(7)°. The structure was solved by using 4439 independent reflections down to R value of 0.029. In crystal structure, the tetrachlorocadmiate anion is connected to two organic cations through N-H...Cl hydrogen bonds and van der Waals interaction as to build cation-anion-cation cohesion. The [C6H10N2]2Cd3Cl10 crystallizes in the triclinic system (P1¯MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8bkY=wiFfYlOipiY=Hhbbf9v8qqaqFr0xc9vqpe0di9q8qqpG0dHiVcFbIOFHK8Feei0lXdar=Jb9qqFfeaYRXxe9vr0=vr0=LqpWqaaeaabiGaciaacaqabeaabeqacmaaaOqaaGqaaiab=bfaqnaanaaabaGaeGymaedaaaaa@2D26@ space group). The unit cell dimensions are a = 6.826 (5)Å, b = 9.861 (7)Å, c = 10.344 (3)Å, α = 103.50 (1)°, β = 96.34 (4)° and γ = 109.45 (3)°, Z = 2. The final R value is 0.053 (Rw = 0.128). Its crystal structure consists of organic cations and polymeric chains of [Cd3 Cl10]4- anions running along the [011] direction, in the [C6H10N2]2Cd3Cl10 compounds hydrogen bond interactions between the inorganic chains and the organic cations, contribute to the crystal packing.PACS Codes: 61.10.Nz, 61.18.Fs, 78.30.-j

Conduction mechanism model, impedance spectroscopic investigation and modulus behavior of the organic–inorganic [(C3H7)4N][SnCl5(H2O)]·2H2O compound

In this study, the electric properties and modulus formulation of the compound [(C3H7)4N][SnCl5(H2O)]·2H2O were studied in the 200 Hz to 5 MHz frequency range and the 343–418 K temperature range. Cole–Cole (Z′′ versus Z′) plots of this compound were well fitted to an equivalent circuit formed by a parallel combination of resistance (R), fractal capacitance (CPE) and capacitance (C). Arrhenius behavior of the direct current conductivity confirmed the transitions observed in the calorimetric study. The dependence of AC conductivity on frequency was found to satisfy Jonschers universal power law at different temperatures, σ(ω) = σdc + Aωs. The (AC) electrical conduction in this material is supported by two theoretical models of conduction that can be attributed to the non-overlapping small polaron tunneling (NSPT) model in phase I and the correlated barrier hopping (CBH) mechanism in phases (II) and (III). Moreover, study of the structure–electronic property relationship implied the dominance of proton conduction in the hydrated form of the compound (region I). Moreover, after crystal dehydration (in region II and III), the conduction was assured by the contribution of the movements of anionic and cationic parts. For the modulus formalism, the extracted activation energies from the linear fit of ln(fp) as a function of 1000/T matched well with those obtained from dc conductivity in regions (II) and (III), which confirmed the hopping mechanism in these two regions.

Raman scattering investigation of the high temperature phase transition in [N(C3H7)4]2SnCl6

The phase transition at high temperature of bis-tetrapropylammoniumhexachlorostannate compound has been investigated by Raman spectroscopy as a function of temperature from 303 K to 393 K. While the bands mainly associated with the internal modes of the SnCl6 anions only undergo weak changes, strong evolutions of wavenumbers, widths and intensities of many lines associated with the organic cations are observed with discontinuities in the vicinity of the phase transition at 362 K. The most important changes are observed for two lines at 1137.5 cm(-1) and 1159.4 cm(-1) (at room temperature) issued from twisting of CH2 groups and skeletal deformation of the cations. The spectral characteristics of these lines are analyzed and consistently described in the framework of an order-disorder model for the phase transition. The temperature dependency of the reduced peak intensity allowed to determine the critical exponents and evolution of the correlation length on approaching the transition.

Raman scattering study of temperature induced phase transition in [C8H10NO]2 [ZnCl4]

The Raman spectra of bis (4-acetylanilinium) tetrachloridozincate single crystals were studied in the range of 100-3500 cm−1 as a function of temperature of 298 K to 398 K. The bands mainly associated with the internal modes of the ZnCl4 anions only undergo weak changes. However, the strong evolutions of wavenumbers, widths and intensities of many lines associated with the organic cations are observed with discontinuities in the vicinity of the phase transition at 351 K. A phase transition at Tc = 351K was observed and characterized by the differential scanning calorimetry (DSC). The most important changes are observed for two lines at 3197.13 cm−1 and 3167.10 cm−1 (at room temperature) issued from asymmetric and symmetric stretching vibrations of (C-H) band and (NH3) group, respectively. The spectral characteristics of these lines are analyzed and consistently described in the framework of an order–disorder model for the phase transition.

Monitoring dehydration of the organic-inorganic [(C3H7)4N][SnCl5(H2O)]·2H2O compound using simultaneous thermal and Raman studies.

In this work we report the experimental studies of the structural phase transition in the [(C3H7)4N]SnCl5(H2O)]·2H2O compound by differential scanning calorimetric (DSC) and Raman spectroscopic. The X-ray powder diffraction study of the [(C3H7)4N][SnCl5(H2O)]·2H2O sample at room temperature showed that this compound is monoclinic and has P121/c1 space group. Differential scanning calorimetric disclosed two types of phase transitions in the temperature range 356-376 (T1) K and at 393K (T2) characterized, by a loss of water molecules and probably a reconstruction of new anionic parts after T2 transition. The Raman scattering spectra recorded at various temperatures in the wavenumber range from 100 to 3800cm(-1) covering the domains of existence of changes in the vicinity of the two phase transitions detected by DSC measurement. A detailed study of the spectral parameters (wave number, reduced intensity and the full width at half maximum) as a function of temperature of a chosen band, associated with (νs(SnO)+νs(SnCl)), based on an order-disorder model allowed us to obtain information relative to the activation energy and correlation length.