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Good quality single crystals of benzimidazolone (CHNO) were grown by slow evaporation of a solution at room temperature. The structure of the compound was determined by single-crystal X-ray diffraction. The compound was found to crystallize in monoclinic space group P2/ n with Z = 4; the molecule is symmetrical to the mirror. The unit cell dimensions are: a = 5.20903(1) Å, b = 5.0557(1) Å, c = 23.4320(3) Å, and V = 627.26(5) Å. The bicyclic system adopts a planar conformation and an intermolecular hydrogen bond is formed between the NH group and the oxygen atom of a neighbouring molecule. Thermal analysis was used to study heat transfer through the structure and Fourier transform infrared (FTIR) and polarized Raman spectral analysis were used to confirm the presence of compound's functional groups. The experimental results were compared with those obtained theoretically by calculation, for example by use of the 3-21G* ab-initio method. [ABSTRACT FROM AUTHOR]

The present paper undertakes the study of a new hybrid compound [2-CH3C6H4NH3]2SeO4 characterized by the X-ray diffraction, IR, DFT calculation, TG-DTA, DSC and electrical conductivity. This new organic-inorganic hybrid compound crystallizes in the monoclinic system with P21/c space group and the following parameters a = 14.821 (5) Å; b = 16.245 (5) Å; c = 6.713 (5) Å; ß = 102.844 (5)°, Z = 4 and V = 1575.8 (14) ų. The atomic arrangement can be described as isolated tetrahedral SeO42- connected with the organic groups by means of NH⋯O hydrogen bonds to form infinite sinusoidal chains in the c-direction. BHHLYP/6-311g** method was used to determine the harmonic frequencies for two optimized cluster structures. The calculated modes were animated using the Molden graphical package to give tentative assignments of the observed IR spectra. Thermal analysis of the title compound does not indicate the occurrence of a phase transition in the temperature range of 300-650 K. Dielectric study of this compound has been measured, in order to determine the conductivity. The conductivity relaxation parameters associated with some H+ conduction have been determined from an analysis of the M"/M"max spectrum measured in a wide temperature range. [ABSTRACT FROM AUTHOR]

A novel cadmium cyclohexaphosphate (C5H14N2)2Cd2Cl2P6O18.4H2O has been prepared and characterized by single-crystal X-ray diffraction, infrared and Raman spectroscopies, thermogravimetric analysis, and cyclic voltammetry. The structure consists of vertex linked of CdO5Cl octahedral and P6O18rings assembled into a two-dimensional macroanionic layers. Organic double-protonated homopiperazine cations are located between these layers and interact with the framework both electrostatically and via hydrogen bonds of N–H···O(Cl). [Supplemental materials are available for this article. Go to the publisher's onlineedition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the following free supplemental files: Additional figures] [ABSTRACT FROM PUBLISHER]

Abstract: The framework flexibility of the nanosized rhombohedrally distorted titanosilicate analog of the mineral pharmacosiderite (RTS) has been in situ studied by powder X-ray diffraction at elevated temperatures. Between 30 and 175°C the rhombohedral lattice showed tendency to shrink and open the angle of the axes. At 125°C the cell distortion resulted in pseudo cubic cell metrics where the reflections (021), (01−2), (211), (220), (301) and (311) have been reduced. After heating at 175°C the recovery of the reduced reflections has not been completed and the lattice remained shrank at room temperature. [Copyright &y& Elsevier]

Abstract: Good transparent single crystals of l-phenylalanine l-phenylalaninium malonate (LPPMA) have been grown successfully by slow evaporation technique from aqueous solution. Single crystal X-ray diffractometer was utilized to measure unit cell parameter and to confirm the crystal structure. The chemical structure of compound was established by FT-NMR technique. The vibrational modes of the molecules of elucidated from FTIR spectra. Its optical behaviour has been examined by UV–vis spectral analysis, which shows the absence of absorbance in the visible region. Thermal properties of the LPPMA crystal were carried out by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) techniques, which indicate that the material does not decompose before melting. The melting point of grown crystal was observed as 180°C by melting point apparatus. The NLO property was confirmed by the powder technique of Kurtz and Perry. The dielectric behaviour of the sample was also studied for the first time. [Copyright &y& Elsevier]

Abstract: Thermally induced intermartensitic transformation in polycrystalline Ni52.5Mn23.7Ga23.8 has been investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It is found that after annealing at 500°C for 4h an intermartensitic transformation, seven-layered orthorhombic martensite (7M) → five-layered tetragonal martensite (5M), appears in polycrystalline Ni52.5Mn23.7Ga23.8 alloy quenched from 800°C, where the sequence of phase transformations is austenite phase (A) → 7M→5M during cooling and 5M→7M→A during heating. The intermartensitic transformation is an independent phase transformation, but the critical transition temperatures and the transformation temperature ranges of 7M→5M are strongly affected by the martensitic transformation. [Copyright &y& Elsevier]