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Influence of organic dopants (L-alanine and L-arginine) on structural, spectroscopic and thermal properties of ammonium dihydrogen phosphate crystal

Parikh K. D., Joshi J. H., Joshi M. J.

Materials Science Poland

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2017

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Vol. 35, No. 3

632--638

EN

Ammonium dihydrogen phosphate is a popular nonlinear optical crystal used for second harmonic generation efficiency improvement in pump lasers. Due to molecular chirality and zwitterionic structure, amino acids are used to enhance various properties of ADP crystal. The single crystals of ammonium dihydrogen phosphate (ADP) added with different concentrations (0.3 wt.%, 0.4 wt.% and 0.5 wt.%) of amino acids (L-alanine and L-arginine) impurities were grown using slow evaporation solution growth (SESG) technique at room temperature. To study the structural properties, powder XRD study was carried out which revealed that all the grown crystals have tetragonal structural symmetry. The presence of various functional groups was confirmed using FT-IR spectroscopy. The thermal spectra (TGA/DTA/DSC) were recorded for all grown samples to determine their decomposition. Also kinetic and thermodynamic parameters were determined from the thermal study.

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Optical, structural and electrical properties of pure and urea doped KDP crystals

Babu B., Chandrasekaran J., Balaprabhakaran S., Ilayabarathi P.

Materials Science Poland

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2013

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Vol. 31, No. 1

151-157

EN

Single crystals of good optical quality, made of potassium dihydrogen phosphate (KDP) doped with urea were grown by slow evaporation solution growth technique at a constant temperature of 35 C. Optical absorption and dielectric properties were studied for pure and urea doped KDP crystals. Using powder XRD studies, crystalline nature of pure and urea doped KDP crystals was confirmed. AC conductivity was measured for the grown crystals. DC electrical conductivity and photoconductivity studies were carried out for pure and urea doped KDP crystals and the differences caused by the dopant were also discussed.

3

Studies on Cobalt(II), Nickel(II), Copper(II) and Zinc(II) Complexes Involving a Bidentate Schiff Base Ligand

Sivasankaran Nair M., Joseyphus R. S., Dhanaraj C. J.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 9

1529-1535

EN

Co(II), Ni(II), Cu(II) and Zn(II) complexes of Schiff base, derived by the condensation of indole-3-carboxaldehyde and beta-alanine, were synthesized and characterized by elemental analysis, conductance measurements, IR, electronic spectra, magnetic measurements and powder XRD. The analytical data show the composition of the metal complex to be ML2, where L is the Schiff base ligand. The conductance data indicate that all the complexes are non-electrolytes. IR results demonstrate the bidentate binding of the Schiff base ligand in volving azomethine nitrogen and carboxylato oxygen atom. The electronic spectral measurements indicate that Co(II) and Ni(II) complexes have pseudo tetrahedral geometry, while Cu(II) complex is square planar. The magnetic measurements show paramagnetic behaviour for Co(II), Ni(II) and Cu(II) complexes. The powder XRD studies show that Ni(II) and Zn(II) complexes are crystalline, while the Co(II) and Cu(II) complexes are amorphous. The crystallite size of the Zn(II) complex was found to be in the nanocrystalline regime. Antimicrobial studies indicate that the metal complexes are found to be more active than the ligand. Among the metal complexes, the Co(II) and Cu(II) complexes were more active compared to that Ni(II) and Zn(II) complexes.