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Effect of L-asparagine as dopant on the growth and characteristics of ammonium tetroxalate dihydrate single crystal

Jerusha Eunice, Kirupavathy S. Shahil

Materials Science Poland

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2020

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Vol. 38, No. 1

48--61

EN

Single crystals of L-asparagine doped ammonium tetroxalate dihydrate were grown using slow evaporation solution growth technique with deionized water as a solvent. The shift and intensity of the peaks in the single crystal X-ray diffraction and Fourier transform infrared analyses confirmed the inclusion of L-asparagine in the ammonium tetroxalate dihydrate crystal structure. The optical transmission characteristics viz. optical band gap, optical conductivity, etc., were determined. Thermal studies revealed the occurrence of anomalies at 135.3 °C and 221.7 °C leading to the possibility of phase transitions and thereby, ferroelectric behavior. Vickers microhardness studies enabled determination of various microhardness parameters. Dielectric behavior was analyzed by varying the temperature and frequency. Anomalies were observed at 135 °C and 221 °C suggesting the existence of ferroelectric nature of the compound. Self-defocusing effect was observed. The polarization-electric field hysteresis loops showed a pinched effect due to defects induced by inclusion of dopant. The crystals were characterized by single crystal XRD, FT-IR, DRS, UV-Vis-NIR, Vickers microhardness test as well as thermal and dielectric techniques. In brief, L-asparagine as a dopant in ammonium tetroxalate dihydrate altered various physical properties of the crystals. They were highly transparent in the visible region with a wider optical band gap, softer material than the parent, higher phase transition temperature of 135 °C, negative nonlinearity and self-defocusing ability.

2

Structural, optical, thermal and NLO behavior of zinc hydrogen maleate dihydrate single crystal

Karuna S., Balu A. R., Muthu S., Shyamala D., Delci Z., Ramkumaar G. R.

Materials Science Poland

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2017

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Vol. 35, No. 4

773--784

EN

Single crystal of zinc hydrogen maleate dihydrate (ZHMD) is grown by slow evaporation method at room temperature. The compound crystallizes in triclinic system with noncentrosymmetric space group P1. FT-IR and FT-Raman spectra of ZHMD are recorded. The versatile DFT is employed to understand the band structure of the crystal. Dipole moment of the molecule, ionization energy and electron affinity are established. The potential energy distribution PED of the vibrational modes is calculated using VEDA4. The results of the optimized molecular structure are compared with the single crystal XRD data. The Mulliken and NBO charges are calculated and interpreted. Optical properties of the grown crystal are analyzed using UV-Vis spectrum. Energy gap determined by Tauc plot is in a good agreement with the theoretical value calculated from HOMO-LUMO energies. Thermogravimetric analysis is done to assess the thermal behavior of the ZHMD crystal. Various thermodynamic parameters are calculated using the basis set B3LYP. The first order hyper polarizability values of ZHMD establish its NLO nature. The molecular electrostatic potential MEP of the molecule is obtained. Third-order nonlinear response is studied using Z-scan technique and the corresponding parameters such as absorption coefficient, refractive index and third-order susceptibility are determined.

3

Investigation on nonlinear optical and dielectric properties of L-arginine doped ZTC crystal to explore photonic device applications

Anis M., Hussaini S. S., Shirsat M. D., Muley G. G.

Materials Science Poland

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2016

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Vol. 34, No. 3

548--554

EN

The present study is focused to explore the photonic device applications of L-arginine doped ZTC (LA-ZTC) crystals using nonlinear optical (NLO) and dielectric studies. The LA-ZTC crystals have been grown by slow evaporation solution technique. The chemical composition and surface of LA-ZTC crystal have been analyzed by means of energy dispersive spectroscopy (EDS) and surface scanning electron microscopy (SEM) techniques. The Vicker’s microhardness study has been carried out to determine the hardness, work hardening index, yield strength and elastic stiffness of LA-ZTC crystal. The enhanced SHG efficiency of LA-ZTC crystal has been ascertained using the Kurtz-Perry powder SHG test. The closed-and-open aperture Z-scan technique has been employed to confirm the third order nonlinear optical nature of LA-ZTC crystal. The Z-scan transmittance data has been utilized to calculate the superior cubic susceptibility, nonlinear refractive index, nonlinear absorption coefficient and figure of merit of LA-ZTC crystal. The behavior of dielectric constant and dielectric loss of LA-ZTC crystal at different temperatures has been investigated using the dielectric analysis.

4

Dielectric, etching and Z-scan studies of glycine doped potassium thiourea chloride crystal

Azhar S. M., Anis M., Hussaini S. S., Kalainathan S., Shirsat M. D., Rabbani G.

Materials Science Poland

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2016

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Vol. 34, No. 4

800--805

EN

Glycine doped potassium thiourea chloride (PTC) crystal has been grown by slow solution evaporation technique. The dielectric studies have been employed to examine substantial improvement in dielectric constant and dielectric loss of glycine doped PTC crystal. The etching studies have been performed to investigate the surface quality of this crystal. The z-scan studies have been carried out at 632.8 nm to explore the third order nonlinear optical nature. The negative nonlinear refraction of glycine doped PTC crystal was found to be of 7.27 × 10-12cm2/W. The origin of high magnitude of third order nonlinear optical susceptibility and reverse saturable nonlinear absorption have been investigated. The obtained results were explored to discuss the nonlinear optical applications of PTC crystal.

5

Nonlinear-optical refraction of silver nanoparticle composites

Gamernyk R, Periv M, Malynych S

Optica Applicata

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2014

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Vol. 44, nr 3

389--398

EN

In this paper, the experimental data on nonlinear refraction of silver nanoparticle composites using a standard Z-scan technique are presented. It was found that the colloids of silver nanoparticles of various size possess a defocusing ability. Based on general considerations, one can conclude thermal lens nature of the nonlinear refraction of the colloids. Significantly different magnitudes of the nonlinear refractive index of silver nanoparticles suspended in water and in glycerol can be explained by differences in the specific heat capacity of mentioned fluids. The effective thickness for nonlinear-optical interaction of light with a two-dimensional silver nanoparticle array was estimated.

6

Nonlinear characterization of Mercurochrome dye for potential application in optical limiting

Krishnamurthy R. R., Alkondan R.

Optica Applicata

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2010

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Vol. 40, nr 1

187--196

EN

Thermally induced optical nonlinearity of Mercurochrome dye in methanol solution at four different concentrations and as solid films mixed with polymethylmethacrylate (PMMA) has been carried out using a CW Nd-YAG laser at 532 nm as the source of excitation. The optical response was characterized by measuring the intensity dependent refractive index n2 of the medium using the Z-scan technique. The dye exhibited a negative (defocusing) nonlinearity and large nonlinear refractive index of the order of 10-7 cm2/W. The nonlinear refractive index was found to vary with concentration. The third-order nonlinearity of the dye was dominated by nonlinear refraction, which leads to strong optical limiting of laser. Optical limiting characteristics of the dye at various concentrations in solution and film were studied. The result reveals that Mercurochrome dye can be a promising material for optical limiting applications.