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Abstract: l-arginine phosphate monohydrate is a promising nonlinear organic crystal for higher harmonic generation in place of the conventional potassium dihydrogen phosphate and is a challenging material for laser fusion experiments. The major and inevitable drawback is the formation of microbes for growing bulk single crystals. In this work, l-arginine fluoro phosphate was synthesized by adding 0.25 and 0.75molar concentrations of HF and ortho phosphoric acids in l-arginine. The inherent properties of microbes and photo-induced decomposition were successfully prohibited for more than 50 days due to the presence of fluorine. No microbes were observed when the solution was kept at open atmosphere. The same solution was used for the growth; crystals of identical morphology were obtained. In addition, no tapering effect and coloration were seen. The characterizations like powder XRD, FTIR, UV–VIS–NIR spectroscopy and TG/DTA were carried out. The second-harmonic generation efficiency was confirmed by using Kurtz and Perry method. [Copyright &y& Elsevier]

The nucleation parameters, such as interfacial tension, radius of the critical nucleus and critical free energy change have been estimated for deuterated l-arginine phosphate (dLAP), potassium fluoride mixed dLAP and sodium azide mixed dLAP single crystals. Pure and additive mixed dLAP single crystals are grown by slow cooling technique. The effect of microbial contamination and colouration on the growth solutions has been studied. The crystalline powder of the grown crystals has been examined by X-ray diffraction and thermal analyses in order to estimate the lattice parameters and study thermal properties respectively. [Copyright &y& Elsevier]

Single crystals of Rh-doped BaTiO3 have been grown by high-temperature solution growth technique. The dopant has significant effect on the growth parameters and crystal properties. Bulk single crystals of dimensions 5×5×4 mm3 have been grown with optimized growth conditions. Layer growth and vein-like structure patterns, indicative of 2D-nucleation mechanism, have been observed on the grown crystals. The dopant level in the grown crystals was estimated by EDX analysis. The crystals possess tetragonal structure and the tetragonality decreases for higher dopant concentration. Rh doping in BaTiO3 leads to decrease in dielectric constant and Curie temperature (Tc) values. [Copyright &y& Elsevier]