Synthesis,growth and optical properties of semi organic non linear optical single crystal: l-Arginine acetate

In the recent past, nonlinear optical materials are getting attention in the field fibre optic communication and optical signal processing. In the present study, the title compound was successfully synthesized by conventional chemical reaction and then the single crystal was grown by slow evaporation solution growth technique. l-Arginine acetate (LAA) is semi organic non linear optical single crystal and crystallizes in noncentrosymmetric space group. The grown good quality single crystals have been analyzed by different characterization analyses such as powder X-ray diffraction, high resolution X-ray diffraction (HRXRD), Raman spectroscopy, photoluminescence, SEM, micro-hardness, thermal and birefringence analyses.     

Growth and characterization of semi organic nonlinear optical l-Valine Ferric Chloride single crystal by solution growth technique

l-Valine Ferric Chloride single crystal is a new semi organic nonlinear optical material. It has been grown from a mixture of aqueous solutions of l-Valine and Ferric Chloride by slow evaporation solution growth technique at room temperature for the first time. Single crystal XRD analysis revealed that the crystal system belongs to Cubic P with cell parameters are a = 24.38 Å, b = 24.38 Å, c = 24.38 Å and volume is 14,485 Å³. The UV spectrum shows existence of wide transparency window suitable for optoelectronic applications. Thermal stability and melting temperature of the as grown crystal was identified from TG-DTA analysis. Spectroscopic studies have been carried out for analyzing the presence of functional groups, thermal stability and phase transition of the grown crystal. The dielectric loss and the dielectric constant of the crystals were measured as a function of frequency. Photoluminescence study was carried out for grown crystals and the maximum emission occurs has good optical transmission in the entire visible region. Second harmonic generation (SHG) conversion efficiency has been estimated.     

Crystal growth,structural and photoluminescence studies of L-tyrosine hydrobromide semi organic single crystal

Nearly perfect single crystal of L-tyrosine hydrobromide (LTHB) has been grown at room temperature from the saturated solution prepared from the solvent with optimised normality (2N) using slow evaporation solution growth technique. Crystal system and lattice parameters have been estimated by single crystal X-ray diffraction analysis. Prominent peeks of powder X-ray diffraction pattern have been indexed and diffraction data have been presented. The presence of various functional groups in LTHB has been identified by vibrational and Nuclear Magnetic Resonance spectral study. The crystalline nature and defect during the growth has been studied by obtaining high resolution X-ray diffraction curve (rocking curve) for the title crystal and detailed explanation is given in this paper. Cyclic voltammetric behaviour and photoluminescence properties of LTHB have also been investigated.     

Synthesis,growth, optical properties of a new metalic crystal

The present fascinating field of research is synthesize, grow, and characterize NLO crystals. Optically good quality single crystals of Potassium Thiourea Carbonate (PTC) crystals have been grown by a slow evaporation method. The grown crystals were characterized by powder X-ray diffraction (XRD), FTIR, UV–vis, micro hardness, impedence analysis. FTIR studies confirm the functional groups present in the grown crystal. The UV–vis spectrum showed the transmitting ability of the crystals in the visible region. Vickers micro hardness is showed the hardness of the material. The impedence of the crystal for various frequencies is also reported.     

Growth and characterization of an efficient semi organic single crystal: Sodium hydrogen oxalate monohydrate

A highly proficient nonlinear optical compound Sodium Hydrogen Oxalate Monohydrate (SHOM) single crystal under semi organic category has been grown-up by the process of slow solvent evaporation. The triclinic structure and cell parameters of SHOM was revealed from X-ray diffraction analysis. The examination of FTIR was done to determine the existence of various functional groups present in the SHOM crystal. The mechanical stability is evaluated from Vicker's microhardness tester and related mechanical parameters were assessed. The multiple shot laser damage threshold was examined to be 2.65 GW/cm². TG/DTA analysis is carried out to appraise the thermal limit of the grown material. The absorbance spectrum was analyzed from UV–vis analysis which verifies high transparency of the grown crystal and various optical constants were also estimated. The third order nonlinearity, two-photon absorption and self-defocussing effect of the grown material was established from the Z-Scan approach. The results favoring the materials suitability over nonlinear optical applications are reported.     

Synthesis and growth of sodium bitartrate monohydrate a new organometallic nonlinear optical single crystal

Sodium bitartrate monohydrate (SBTMH) a new organometallic nonlinear optical material, with molecular formula, [C₄H₅NaO₆ · H₂O] has been synthesized at ambient temperature. Spectral, thermal and optical techniques have been employed to characterize the new material. Bulk single crystals of size 13 × 4 × 4 mm³ of SBTMH have been grown by slow cooling method. The unit cell parameters of the grown crystal were determined by single crystal XRD. Functional groups present in the sample were identified by FTIR spectral analysis. Thermal stability of SBTMH was determined using TGA/DTA. The grown crystals exhibit nonlinear properties. The dielectric response of the crystal with varying frequencies was studied. The optical transparency range and the lower cut-off wavelength of the material were identified from the UV–vis–NIR absorption spectrum.     

Far-infrared optical properties of YVO4 single crystal

Near-normal incident infrared reflectivity spectra of a (001) YVO₄ single crystal have been measured at different temperatures in the frequency region between 100 and 6000 cm^-1. The reflectivity spectra are analyzed with the factorized form of the dielectric function, and the dielectric properties and optical conductivity of the YVO₄ crystal are obtained. From the TO/LO splitting, effective charges at different temperatures are calculated to study the ionicity of YVO₄. The internal modes of the VO₄^3- ion and the external modes of the Y(VO₄) lattice are compared with SiO₄^4- in zircon and with other rare-earth vanadates.     

FIR optical properties of single crystal Ba-and Sr-hexaferrite

Far-infrared reflectivity measurements on single crystal barium and strontium hexaferrite are presented. The infrared active TO, and the associated LO phonon frequencies and the dielectric permittivity functions for E ⊥c have been determined using a fitting procedure based on a four parameter model. The infrared active modes of these compounds (space group D⁴_6h have been determined by group theoretical analysis and the results compared with the spectroscopic measurements.     

Synthesis,growth and characterization of a semiorganic nonlinear optical single crystal: L-Valine cadmium bromide

A semiorganic nonlinear optical material L-valine cadmium bromide was synthesized and single crystal grown from an aqueous solution by the method of slow evaporation technique at room temperature. The grown crystal was characterized by Powder X-ray diffraction and FT IR studies. The LVCB crystallizes in monoclinic system with cell parameters a = 10.144(2) Å, b = 5.54(1) Å, c = 12.07(2) Å, β = 109.115(2)° with space group P₂₁. Thermal behavior and stability of crystal were studied using thermogravimetric analyses (TGA) and differential thermal analysis (DTA) techniques. The suitability of this material for NLO application was studied by optical absorption studies and second harmonic generation (SHG) efficiency measurement by Kurtz–Perry powder method.     

Synthesis, crystal growth and characterization of a metal-organic nonlinear optical tri-allylthiourea mercury chloride single crystals

Metal-organic nonlinear optical material tri-allylthiourea mercury chloride single crystal was grown using low temperature solution growth method. The growth parameters such as pH and temperature were optimized for getting colorless single crystals. The X-ray rocking curve measurement shows that the grown crystal was free from internal structural grain boundaries. The structural, spectral, optical and thermal properties of the grown specimen were studied using various characterization techniques. The defects present in the grown crystals were studied with chemical etching analysis. The results show that the grown crystals are suitable candidates for nonlinear optical applications.     

Synthesis and characterisation of glycine sodium nitrite crystals having non linear optical behaviour

Glycine sodium nitrite (GSNi) having non linear optical efficiency more than KDP crystal has been obtained from solutions by slow cooling technique. The crystals are found to be chemically and thermally stable with orthorhombic unit cell. The presence of wide transparency window in UV–Visible region makes GSNi suitable for opto-electronic device applications. It has second harmonic generation efficiency of 1.273 times that of standard KDP crystal. GSNi crystal belongs to soft category of materials with work hardening index of 2.33. Crystals introduced in timer circuit gave a stable output with the capacitance value of 236 pF. I–V characteristic indicates a safe operating range of 300 V/cm. GSNi is seen to behave as a normal dielectric with applied frequency and crystals exposed to light exhibit negative LDR characteristic which is attributable to space charge formation.     

Bulk crystal growth and characterization of non-linear optical bisthiourea zinc chloride single crystal by unidirectional growth method

The unidirectional crystal growth method has been employed for the bulk growth of semi-organic non-linear optical bisthiourea zinc chloride single crystal along a-axis with high solute-crystal conversion efficiency. Single crystal X-ray diffraction studies confirm the orthorhombic structure. Optical studies reveal very high transmission of the crystal along the growth axis. Dielectric study shows that the dielectric constant decreases with increase in frequency. Microhardness measurements along the growth axis enunciate the favorable hardness behavior.     

Synthesis,growth and properties of a novel organic nonlinear optical material: Benzimidazolium perchlorate

Benzimidazolium perchlorate (BDP) a novel organic nonlinear optical material has been grown by slow evaporation technique. Growth parameters such as metastable zone width and induction period were determined. The relative second harmonic generation (SHG) efficiency of the material was investigated for the first time in the literature and was found to be 1.2 times higher than that of KDP. The grown crystals were subjected to X-ray diffraction, absorption spectrum, Fourier transform infrared (FT-IR) spectroscopy, thermal behavior, CHN analysis, and micro hardness studies.     

Crystal growth, optical properties, and laser operation of Yb3+-doped NYW single crystal

Laser crystal Yb³⁺-doped NaY(WO₄)₂ (Yb:NYW) with excellent quality has been grown by Czochralski technique. The rocking curves from (400) plane of as-grown Yb:NYW crystal was measured and the full-width value at half-maximum was 19.92″. The effective segregation coefficients were measured by the X-ray fluorescence method. The polarized absorption spectra and the fluorescence spectra of Yb:NYW crystal were measured at room temperature. The fluorescence decay lifetime of Yb³⁺ ion in NYW crystal has been investigated. The spectroscopic parameters of Yb:NYW crystal are calculated and compared with those of Yb:YAG crystal. A continuous wave output power of 3.06 W at 1031 nm was obtained with a slope efficiency of 42% by use of diode pumping.     

Synthesis and optical properties of organic semiconductor: zirconia nanocomposites

Oxide nanoparticles were used as carrier for organic semiconductor materials. Stable suspensions of ZrO₂ nanoparticles coated with anthracene, pentacene, or para-hexaphenyl were obtained by microwave plasma synthesis of ZrO₂ cores, subsequent in situ coating with organic compounds, and in situ dispersion in ethylene glycol. Powders of coated oxide nanoparticles were synthesized for comparison. The successful coating and a small uniform size distribution of the ZrO₂ cores were confirmed by comprehensive characterization including photoluminescence, absorption spectroscopy, electron microscopy, electron energy loss spectroscopy, mass spectrometry, and X-ray diffraction. Powder compacts of anthracene-coated ZrO₂ particles showed good air stability and a significant blue shift accompanied by an attenuation of the emission lines at higher vibronic orders in comparison to samples of pure anthracene as received. For para-hexaphenyl-coated nanoparticles, the same photoluminescence characteristics are observed as for pure para-hexaphenyl. In the case of pentacene-coated nanoparticles indication for degradation is found.     

Synthesis,growth and characterization of a novel semiorganic nonlinear optical single crystal: l-Asparagine cadmium chloride monohydrate

The semiorganic single crystal of l-asparagine cadmium chloride monohydrate was grown by slow evaporation solution growth technique at room temperature. The presence of various functional groups has been identified by using FT IR spectral analysis ranging between 4000 and 400 cm^?1. Chemical composition of the synthesized material was confirmed by elemental analysis. The crystalline nature of new crystal was confirmed by powder XRD pattern. The UV–vis–NIR spectroscopic study revealed that the grown crystal has good optical transmittance. The dielectric constant has been carried out over a frequency range from 100 Hz to 1 MHz. The mechanical strength was studied using Vicker's microhardness tester.     

First-principles study of electronic and optical properties of the optical non linear LiMoO3(IO3)

The electro-optical properties, including: energy density of states function, dielectric function, refraction coefficient, extinction coefficient, band structure, energy gap and optical conductance of LiMoO₃(IO₃) structure with single-crystal data are computed and discussed in this paper. The LDA + U and generalized gradient approximations (GGA) with the full-potential linearized augmented plane wave method (FP-LAPW) in the framework of density functional theory (DFT) are used to compute the energy gap and other properties of this structure by considering the orbital dependent potential for coupled d orbital brought from experimental results and the U is applied to the Mo d-manifold. The results of energy gap are 2.1 eV and 1.5 eV for LDA + U and for GGA methods, respectively, which LDA + U method result is very close to experimental results.     

Effect of Co2+ on the growth,optical properties and laser damage threshold of potential nonlinear optical l-alanine single crystal

Good transparent bulk single crystals of pure l-alanine (LA) and cobalt doped LA crystals have been synthesized and successfully grown by slow-cooling method from their aqueous solutions. The concentration of metal dopants in the mother solution with 0.5 mol% for cobalt was carried out individually and crystals were obtained with well defined morphology. The as grown metal doped and pure single crystals were characterized by single crystal XRD studies which confirm that the incorporation of metallic dopants has not changed the basic structure of the parent crystal. The absorption of these crystals was analyzed and the result confirms that they possess low absorption in the range 230–1100 nm. Fourier transform infrared (FTIR) spectroscopy was carried out to investigate the molecular vibrations of these crystals and to confirm the incorporation of the dopants. The thermal properties have been studied by TGA/DTA curves. The EDAX measurement and surface morphology were studied for pure and metal doped LA crystals. The second harmonic generation (SHG) signals were observed using Nd: YAG laser with fundamental wavelength of 1064 nm in pure and metal doped crystals. The laser damage threshold was measured for pure and metal doped LA crystals and also tested by using a Q-switched Nd: YAG laser showed enhanced LDT value for metal (Co²⁺) doped LA crystal compared to pure LA crystal due to the metallic substitutions thus proving their useful candidature for nonlinear optical applications.     

Synthesis,growth and physicochemical properties of an organometallic nonlinear optical crystal: Mercury cadmium chloride thiocyanate

SCN⁻ ligand based organometallic non-linear optical mercury cadmium chloride thiocyanate (MCCTC) crystals are grown from water plus methanol mixed solvent by slow evaporation technique. The grown crystals are confirmed by single crystal X-ray diffraction analysis. MCCTC exhibits a SHG efficiency which is nearly 17 times more than that of KDP. The dielectric constant, dielectric loss and ac conductivity measurements of the sample have been carried out for different frequencies (100 Hz to 5 MHz) and, temperatures (308–388 K) and the results are discussed. Photoconductivity study confirms that the title compound possesses negative photoconducting nature. The surface morphology of MCCTC was also investigated.     

Unidirectional growth,linear and nonlinear optical,dielectric and mechanical properties of organic adduct of l-tartaric acid nicotinamide

An attempt has been made to grow l-tartaric acid nicotinamide (LTN); a complex of tartaric acid, by employing a modified unidirectional method. The crystalline structure and quality are investigated by single crystal XRD and rocking curve studies. The linear and nonlinear optical properties are studied by UV–vis-NIR spectral analysis, SHG test, phase matching and laser induced damage threshold measurement. For comparison, parallel growth of the crystal was carried out by conventional method and the properties of the LTN samples grown by the conventional and unidirectional methods are investigated. The mechanical, photoconductivity and dielectric behavior of LTN crystals are also investigated.