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New mixed crystal of Yb: Y 0.78 Lu 0.22 VO 4 with Yb ion concentration of 0.3 at% was grown by Czochralski method. Transmission synchrotron X-ray topography implies that this mixed crystal follows a rotational growth pattern. Crystal structure of this crystal was determined by X-ray diffraction. It showed that this crystal possesses a tetragonal zircon structure (ZrSiO 4 , space group I41/amd), as YVO 4 and LuVO 4 do. Thermal properties of this crystal were characterized by measuring its specific heat, thermal expansion coefficients and thermal conductivities. The specific heat was determined to be 0.500 J g −1 K −1 at 293 K. The average linear thermal expansion coefficients were calculated to be α 11 = 1.73 × 10 −6 K −1 and α 33 = 9.43 × 10 −6 K −1 , over the temperature range of 300–777 K. The thermal conductivities were calculated to be κ 11 = 5.47 W m −1 K −1 and κ 33 = 6.64 W m −1 K −1 at 303 K. Continuous-wave (cw) laser test on Yb: Y 0.78 Lu 0.22 VO 4 was conducted at room temperature in the wavelength range of 1035.7–1048.3 nm, and a 13.5% optical-to-optical efficiency was achieved. The good thermal properties of Yb:Y 0.78 Lu 0.22 VO 4 mixed crystal and its attractive cw laser performance make it very suitable for practical applications. [ABSTRACT FROM AUTHOR]

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]

Highlight: [•] Systematic studies have resulted in the growth of high quality nonlinear optical material. [•] The grown crystal has high laser damage threshold and the NLO efficiency is 1.6 times greater than that of KDP. [•] The grown crystals were characterized and reported for the first time. [•] The results suggest that LPB could be expected to be a suitable material for the NLO device fabrication. [ABSTRACT FROM AUTHOR]

Abstract: Single crystals of novel semi-organic novel nonlinear optical material bis L-glutamine sodium nitrate (BGSN) were grown by slow evaporation technique. Single crystal XRD revealed that material crystallized in orthorhombic crystal system with non-centrosymmetric space group P212121. Molecular mass of BGSN has been measured by using mass spectroscopic analysis. Surface morphology of the grown crystal was studied by scanning electron microscopy (SEM). The presence of sodium in the compound and composition of grown crystals was confirmed on the basis of energy dispersive analysis of X-ray (EDAX). Photoluminescence study was carried out using a Xe-lamp source in the range of 250–450nm. The thermal stability of the crystal is investigated using thermo-gravimetric analysis studies. Second harmonic generation (SHG) efficiency of the grown crystal was measured by Kurtz powder method. [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: Organic nonlinear optical crystal of 1-chloro-2,4-dinitrobenzene has been successfully grown by low temperature solution growth technique. Good optical quality single crystals of size 28mm×11mm×5mm are obtained. Grown crystals were subjected to X-ray powder diffraction analysis, FT-IR, FT-Raman, proton nuclear magnetic resonance (PNMR) and etching studies. Thermal properties of the grown crystals were studied by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA). UV–vis studies show the cutoff wavelength is less than 400nm. Nonlinear optical property of the crystal was studied by Kurtz powder technique using Nd:YAG laser and the crystal exhibits second harmonic generation property. [Copyright &y& Elsevier]