Crystal structure, vibrational studies and optical properties of a new organic-inorganic hybrid compound (C10H28N4)CuCl5Cl⋠4H2O.

A new organic-inorganic hybrid material, 1,4-bis(3-ammoniumpropyl) piperazinium pentachloridocuprate(II) chloride tetrahydrate [(C10H28N4)CuCl5Cl⋅4H2O], has been synthesized and characterized by X-ray diffraction, UV-visible absorption, Infrared and Raman spectroscopy. The compound crystallizes in the orthorhombic system and Pnma space group with a=8.18 (3)Å, b=10.96 (5)Å, c=21.26 (9)Å, V=2254.3 (15)Å(3). In this structure, the Cu(2+) ion, surrounded by five chlorides, adopts the square pyramidal coordination geometry. The structure of this compound consists of tetraprotonated 1,4-bis(3-ammoniumpropyl) piperazinium cations and the anionic sublattice is built up of isolated, square pyramid [CuCl5](3)(-) units, chloride ion Cl(-) and water molecules connected with each other by hydrogen bonds. Organic and inorganic entities are interconnected by means of hydrogen bonding contacts [NH⋯O(Cl), O(W)H⋯Cl and O(W)H⋯O]. Furthermore, the room temperature IR and Raman spectra of the title compound were recorded and analyzed on the basis of literature data. The optical study was also investigated by UV-Vis absorption. In fact, the organic-inorganic hybrid crystal thin film can be easily prepared by spin-coating method from the ethanol solution of the (C10H28N4)CuCl5Cl⋅4H2O hybrid compound and it showed absorptions characteristics of CuCl based layered compounds centered at 275 and 374 nm.

Crystal structure, vibrational studies, optical properties and DFT calculation of bis 2-aminobenzothiazolium tetrachloridocuprate.

The zero dimensional organic-inorganic hybrid compound (C7H7N2S)2CuCl4 was synthesized and characterized by X-ray diffraction, infrared absorption, Raman spectroscopy scattering and optical transmission measurements. The title compound crystallizes in the monoclinic system with P21/c space group. The unit cell parameters are a=7.060 (5) Å, b=9.748 (5) Å, c=14.037 (5) Å, ß=98.520 (5)° and Z=2. The copper (II) ion has square planar coordination environment and the structure is built up from isolated [CuCl4](2)(-) anion surrounded by organic cations connected together via N-H⋯Cl hydrogen bonding. Room temperature IR and Raman spectra of the title compound were recorded and analyzed. The theoretical geometrical parameters in the ground state have been investigated by density functional theory (DFT) with the B3LYP/LanL2DZ level of theory. The organic-inorganic hybrid crystal thin film can be easily prepared by spin-coating method from the ethanol solution of the (C7H7N2S)2CuCl4 compound and it showed characteristic absorptions of Cu-Cl based layered perovskite centered at 288 and 400 nm.

Structural, vibrational and DSC investigations of the bis-4-benzyl piperidinium tetraoxoselenate monohydrate crystal.

A new organic-inorganic salt, bis-4-benzyl piperidinium tetraoxoselenate monohydrate has been synthesized and characterized by X-ray diffraction, FT-IR and FT-Raman spectroscopies. The title compound crystallizes in the monoclinic system P2(1)/c at room temperature with the following parameters: a=8.617(3)Å, b=27.140(9)Å, c=10.926(5)Å, ß=96.46(4)° and Z=4. Its vibrational spectra have been discussed on the basis on quantum chemical density theory (DFT) calculation using B3LYP/6-31G(*) approach. The role of the intermolecular interaction in this crystal is analyzed. Acidic protons of the selenate group were transferred to the organic cation giving the singly-protonated cation. The ability of ions to form spontaneous three-dimensional structure through O-H···O and N-H···O hydrogen bond is fully utilized. These hydrogen bonds give notable vibrational effects.

Vibrational study of phase transition in N-benzyl methyl ammonium dihydrogenmonophosphate monohydrate.

Raman spectra (100-3200 cm(-1)) of polycrystalline samples of C(6)H(5)CH(2)NH(2)CH(3)H(2)PO(4).H(2)O were studied at temperature ranging from 77 to 350 K. By comparison with homologue compounds and calculated wavenumbers, an assignment of the observed bands is proposed. The thermal evolution of Raman spectra reveals an order-disorder phase transition at about 120 K involving the hydrogen bonds coupled with the distortion of the organic cations. The line at 244 cm(-1)assigned to tau(CH(3)) shows a remarkable evolution across the transition. Therefore, a careful analysis of the thermal evolution of this mode was performed using Porto model. The activation energy, obtained from the plot of Deltanu(1/2) versus temperature, is E(a)=1.27 kcal mol(-1). This value is of the same order of magnitude as the one found for homologue hydrogen bonded compounds.

Structural and vibrational study of a new organic hydrogen sulfate.

This paper presents a structural and vibrational study of a new compound, namely, monohydrate 1,5-pentanediammonium hydrogen sulfate (NH3(CH2)5NH3(HSO4)2.H2O). The X-ray crystal structure shows that this compound crystallizes in the monoclinic system, space group P2(1)/c, with the lattice parameters a=9.2250(2)A, b=7.7540(4)A, c=20.8520(1)A, beta=116.23(3) degrees, V=1337.97(10)A3, and Z=4. From the structural investigations, it is found that the studied compound is built by infinite anionic ribbons parallel to the "a" axis. These ribbons form tunnels in which organic cations are inserted. Infrared (IR) spectrum of the compound in the 300-4000 cm(-1) spectral region is reported. A tentative assignment of the observed bands, supported by a molecular orbital semi-empirical calculation, is given.

Vibrational study and fluorescence bands in the FT-Raman spectra of Ca(10-x)Pb(x)(PO4)6(OH)2 compounds.

About 40 apatitic compounds, stoichiometric or not, with different substitutions like lead, sodium and cadmium were investigated using infrared, Raman and FT-Raman spectroscopies. In the Ca(10-x)Pb(x)(PO4)6(OH)2 sequence (x runs from 0 to 10), the evolution of the fluorescence bands observed by FT-Raman, only with stoichiometric entities apatites, is mainly regarded and explained. Important spectral changes concerning the OH- and the PO4(3-) entities occur when 4 < or = x < or = 7. The intensity ratio of the two components of the v1 PO4(3-) mode is shown to be a suitable method to determine the lead content. The weak OH...O hydrogen bonds involving the OH- ions, of which the disorder is discussed, are different for the lead and calcium hydroxyapatites. The evolution of the fluorescence bands, as well as the splitting of the v(OH) mode, are due to the lead distribution in the two sites, with a preference for sites II, of the hydroxyapatite structure. The effect of temperature is also reported.

Synthesis, DTA, IR and Raman spectra of penthylenediammonium hexachlorostannate NH3(CH2)5NH3SnCl6.

The Raman and IR spectra of NH3(CH2)5NH3SnCl6 have been measured at ambient temperature. It is shown that the cations in the compound assume a symmetry lower than C2v. Combination bands observed in the 2100-1800 cm(-1) region in the IR spectrum of NH3(CH2)5NH3SnCl6 indicate that the compound contains the C-NH3 grouping, the bands are discussed and their assignment are suggested. No evidence of existence of hydrogen bonding is found from the infrared spectrum in the region of 2800-3200 cm(-1); anions and cations are found not connected by hydrogen bonding and are therfore isolated. The Raman spectrum of anions can be interpreted in terms of disordered groups, not clearly showing the predicted splitting of bands.