Structural,optical and mechanical property analysis of magnesium sulphate admixtured l-Threonine: A novel optoelectronic material

l-Threonine is an important amino acid and famous due to their property of frequency conversion and electro optic modulation. Single crystals of magnesium sulphate admixtured l-Threonine was grown by slow evaporation technique. Good quality single crystal with dimension 58 × 5 × 10 mm³ was harvested after 60 days. The powder X-ray diffraction pattern of the grown crystal has been indexed. The optical transmission spectrum shows that the magnesium sulphate admixtured l-Threonine possess good optical transparency in the entire visible region with Ultra Violet cut-off wavelength at 250 nm. The presence of fundamental functional groups was identified by Fourier Transform Infra Red spectral analysis. The structure of the grown crystal was established using Fourier Transform-Nuclear Magnetic Resonance spectral analysis. The thermal behaviour of the crystal has been discussed by Thermal Gravimetric Analysis and Differential Thermal Analysis. Magnesium sulphate admixtured l-Threonine was characterized by Energy dispersive analysis of X-ray. The second harmonic generation efficiency of magnesium sulphate admixtured l-Threonine crystal is found to be same as that of potassium dihydrogen phosphate crystal.     

Crystal growth,spectral and NMR studies of nonlinear optical crystal: L-valinium picrate

Organic nonlinear optical material, L-valinium picrate (LVP) was synthesized by slow evaporation solution growth method. The synthesized material was purified by repeated recrystallization. Single crystals of LVP were grown by slow evaporation method using water as solvent. The cell dimensions were obtained by X-ray diffraction study and crystal system was confirmed as monoclinic. The transmission spectrum of LVP was recorded by UV–Vis-NIR spectrometer in the range between 190 nm and 1100 nm which addressed the high percentage of transmission of the sample in the entire visible region. The presence of functional groups was studied by FT-IR analysis. The chemical environment of carbon and hydrogen in the proposed structure of LVP crystal was confirmed by FT NMR studies. The Kurtz-Perry powder SHG measurement was confirmed the frequency doubling of the crystal.     

Linear and nonlinear optical properties of N-(3-nitrophenyl) acetamide single crystals

Optically transparent nonlinear optical bulk single crystal of N-(3-nitrophenyl) acetamide (3NAA) of dimension 7 mm × 6 mm × 5 mm has been grown from its aqueous solution by slow solvent evaporation technique. The grown crystal was characterized by powder X-ray diffraction to confirm the crystal structure. Investigation has been carried out to assign the vibrational frequencies of the grown crystals by Fourier Transform Infrared Spectroscopy and FT-NMR technique. Thermal behaviour of the grown crystals was studied by thermogravimetric analysis. The second harmonic generation efficiency of 3NAA was determined by Kurtz and Perry powder technique. The optical absorption study confirms the suitability of the crystal for device applications. The mechanical properties of the grown crystals have been studied using Vickers microhardness tester. Dielectric, microhardness and photoconductivity studies also carried out for the grown sample.     

Crystal growth,optical and thermal studies of nonlinear optical γ-glycine single crystal grown from lithium nitrate

Single crystals of the nonlinear material γ-glycine have been grown in the presence of lithium nitrate by slow-evaporation method. Structural characterization of the grown crystals was carried out by powder and single crystal X-ray diffraction (XRD) methods and it is observed that the samples crystallize in hexagonal system with non-centrosymmetric space groups. The modes of vibrations of different molecular groups present in glycine have been identified by spectral analyses. UV–visible transmittance study was performed to analyze optical transparency of γ-glycine crystals and found that the crystal was transparent in the entire visible-NIR region. Second harmonic generation (SHG) conversion efficiency has been estimated as 62 mV and the output power by the crystal was 1.72 times that of potassium dihydrogen phosphate (KDP) crystal. The thermal stability and decomposition of the sample have been studied by thermal analysis and it is observed that the γ-glycine crystal have good thermal stability.     

Experimental and theoretical studies on bis(glycine) lithium nitrate (BGLiN): A physico-chemical approach

Good quality and bulk size single crystal (size: 20×13×8 mm³) of bis(glycine) lithium nitrate (BGLiN) was grown by a slow evaporation solution technique from the aqueous solutions at constant temperature i.e. 27 °C using synthesized materials. Crystal system and lattice parameters were determined by single crystals as well as powder X-ray diffraction analysis. The lattice parameters of the titled compound are a=10.0223 Å, b=5.0343 Å, c=17.0510 Å, and V=860.312 Å³ and it crystallized in an orthorhombic system with space group Pca2₁ obtained by single crystal XRD. Elemental composition was confirmed by energy dispersive X-ray spectroscopic analysis. Optical absorption spectrum was recorded and various optical parameters such as optical transmission (~60%), and optical band gap (4.998 eV) were calculated. Photoluminescence study shows that the grown crystal is free from major defects. Crystalline perfection of the grown crystal was assessed and found good. Ground state optimized geometry has been obtained by using DFT with 6-31G(d,p) basis set. HOMO and LUMO energy gap was found to be 6.01 eV and dipole moment was 1.65 D.     

Enhancement of second harmonic generation efficiency: Cs(I)-doped tris(thiourea)zinc(II) sulphate crystals

The effect of dopant cesium (Cs(I)) over a concentration range from 1 to 10 mol% on the growth process, morphology, thermal and optical properties of tri(thiourea)zinc(II) sulfate (ZTS) single crystals grown by slow evaporation solution growth technique has been investigated. Incorporation of Cs(I) into the crystal lattice was well confirmed by energy dispersive X-ray spectroscopy (EDS). The lattice parameters of the as-grown crystals were obtained by single crystal X-ray diffraction analysis. The reduction in the intensities observed in powder X-ray diffraction patterns of doped specimen and slight shifts in vibrational frequencies in fourier transform infrared spectra (FT-IR) indicate the lattice stress as a result of doping. Thermal studies reveal the purity of the material and no decomposition is observed up to the melting point. High transmittance is observed in the visible region and the cut-off λ is ～280 nm. The surface morphology of the as-grown specimens was studied by scanning electron microscopy (SEM). The second harmonic generation (SHG) efficiency of the host crystal is enhanced greatly in the presence of high concentrations of the dopant.     

Synthesis,growth, vibrational,optical and thermal studies of potassium diboro oxalate single crystals

Single crystals of novel semiorganic material, potassium diboro-oxalate (PDO) have been grown from aqueous solution by slow evaporation technique. The lattice parameters for the grown crystals were determined by the single crystal X-ray diffraction analysis and the crystallinity of the grown crystal was confirmed by powder X-ray diffraction analysis. The presence of functional groups was estimated qualitatively by using Fourier transform infrared (FTIR) analysis. The optical absorption spectrum shows that the UV cut-off wavelength for the grown crystal is at 240 nm and the band gap was calculated. The thermal stability of the grown crystal was studied by using TG/DTA analysis. The second harmonic generation and the phase-matchable tests were performed by Kurtz powder technique. The crystal perfection was analyzed by SEM photographs.     

Growth and characterization of pure and doped bis thiourea zinc acetate: Semiorganic nonlinear optical single crystals

Metal–organic coordination complex single crystals bis thiourea zinc acetate (BTZA) and Cd²⁺ doped BTZA have been synthesized and grown successfully by slow-cooling technique from their aqueous solutions. Single crystals of pure and Cd²⁺ doped BTZA with dimensions of 35 × 4 × 2 mm³ and 10 × 5 × 6 mm³, respectively were obtained with well defined morphology. The as grown single crystals are characterized by single crystal XRD studies and melting point measurements which reveal the incorporation of metallic dopants has not changed the structure of the parent crystal. The powder X-ray diffractogram of the grown crystals has been recorded and the various planes of reflection identified shows shift in the peak positions. The metal coordination with thiourea through sulphur in pure and Cd²⁺ doped BTZA were ascertained by FTIR studies and optical absorption study to identify the UV cut-off range. The presence of metals in pure and Cd²⁺ doped BTZA crystal lattice were confirmed by atomic absorption spectroscopy (AAS). The thermal decomposition of pure and Cd²⁺ doped BTZA crystals were investigated by thermo gravimetric analyses (TGA) and differential thermal analysis (DTA) indicate that doped crystals are more stable than pure crystals. The dielectric response of the crystals were studied in the frequency range 100 Hz–5 MHz at different temperatures and the results are discussed. Second harmonic generation (SHG) measurement confirms that the pure and Cd²⁺ doped BTZA have nonlinear optical (NLO) property. Laser damage threshold value of 12.44 MW/cm² has been determined using Q-switched Nd:YAG laser operating at 1064 nm and with 8 ns pulses in single shot mode for pure BTZA single crystal is reported for the first time.     

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.     

Growth of 〈1 0 0〉 directed ADP crystal with slotted ampoule

Good quality ammonium dihydrogen phosphate single crystals have been grown by: (i) Sankaranarayanan–Ramasamy (SR) method and (ii) SR method with slotted ampoule. The grown crystals were subjected to UV–Vis spectroscopy, high-resolution X-ray diffractometer, dielectric, piezoelectric and laser damage threshold studies. Compared to the (1 0 0) plane of the conventional method grown ADP crystal and 〈1 0 0〉 directed SR method grown ADP crystal, the crystal grown by SR method with slotted ampoule has higher growth rate, higher optical transparency, high crystalline perfection, low dielectric loss, high piezoelectric charge coefficient and high laser damage threshold due to diffusion of segregated impurities away from the growing crystal in the slotted ampoule growth.     

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.     

Investigation on mechanical properties of some thiourea complex crystals: Important nonlinear optical materials

In this work the authors have grown good quality single crystals of zinc thiourea sulphate, bis thiourea cadmium acetate, bis zinc thiourea acetate and bis thiourea zinc chloride were grown from slow evaporation solution growth method at ambient temperature and studied their mechanical properties. The crystal system and lattice parameters were confirmed by powder X-ray diffraction analysis. Vickers microhardness of the grown crystals was investigated by using Leitz-Wetzlar (Miniload 2) hardness tester up to an applied load of 120 g. It was observed that, upto 40 g applied load the hardness of the grown crystals increases with increasing the load and thereafter it is practically independent of the indentation load. Meyer's law and Hays–Kendall's law fail to explain the observed load variations. But the variation could be satisfactorily explained by PSR model proposed by Li and Bradt. Classification of cracks and their transition from Palmqvist to median types is explained. The average value of fracture toughness, brittleness index, Young's modulus and yield strength were calculated using expressions for Palmqvist and median types of cracks. Anisotropic nature of the grown crystals was studied using Knoop indentation technique.     

Crystal growth and characterization of L-valine cadmium acetate a semiorganic NLO crystals

A new semiorganic nonlinear optical material, L-valine cadmium acetate, was grown successfully from aqueous solution by slow evaporation method. The grown crystals characterized by using Powder X-ray diffraction analysis confirms the structure of the grown title compound. The functional groups have been identified using FTIR spectral data. Transmittance compound was analyzed by using UV-vis spectrum. The thermal behavior of the grown crystal was determined with the aid of thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The dielectric constant was studied as a function of frequency for various temperatures. The grown crystal has positive photoconductivity nature. The fluorescence spectrum of the crystal was recorded and its optical band gap is about 3.4479 eV. Second order nonlinear optical property of the grown crystal has been confirmed by modified Kurtz–Perry powder second harmonic generation (SHG) test.     

Structural,optical and electrical characteristics of a new NLO crystal

A new nonlinear optical (NLO) organic crystal 1-[4-({(E)-[4-(methylsulfanyl)phenyl]methylidene}amino)phenyl]ethanone (MMP) has been grown by slow evaporation technique at ambient temperature. The crystal structure of MMP was determined by single crystal X-ray diffraction. MMP crystallizes in non-centrosymmetric monoclinic system with space group P2₁. The FT-IR spectrum recorded for new crystal confirmed the presence of various functional groups in the material. MMP was found to be thermally stable up to 300 °C. The grown crystal was optically transparent in the wavelength range of 400–1100 nm. The second harmonic generation (SHG) efficiency of the crystal was measured by the classical powder technique using Nd:YAG laser and was found to be 4.13 times more efficient than reference material, urea. Third order nonlinear parameters were measured by employing the Z-scan technique. The laser damage threshold for MMP crystal was determined to be 4.26 GW/cm². The Brewster angle technique was employed to measure the refractive index of the crystal and the values for green and red wavelengths were found to be 1.35 and 1.33, respectively. The dielectric and electrical measurements were carried out to study the different polarization mechanisms and conductivity of the crystal.     

Synthesis,spectral and thermal characterization of Bis(diethylammonium) tetrachloromercurate(II)-An nonlinear optical material

A new semiorganic compound, bis(diethylammonium) tetrachloromercurate(II) was grown by slow evaporation solution growth technique at ambient temperature from its aqueous solution. The crystal system and the cell parameters have been identified from the powder X-ray diffraction pattern. The UV–visible absorption of the compound shows absorption at 246 nm and there is absorption observed in the entire visible region indicates that the compound can be used as a nonlinear optical material. The UV–visible transmittance spectrum of grown crystal shows a lower cut-off wavelength at 275 nm and it was found that the crystal is suitable for optoelectronic applications. Thermal studies were carried out to find out the thermal stability and confirm the stoichiometric ratio of the compound. The thermal anomalies in DSC study indicate the occurrence of first order transition in the compound at low temperatures. The FTIR spectrum of the compound characterizes various functional groups. The various kinds of protons and carbons were assigned through NMR (¹H and ¹³C) spectroscopic techniques. The SHG efficiency of the compound was studied by Kurtz-Perry power technique and observed that it has SHG efficiency 1.5 times greater than that of potassium dihydrogen phosphate (KDP). The dielectric constant and dielectric loss of the compound decreases with increase in frequency.     

Growth,linear and nonlinear optical studies on guanidinium 4-nitrobenzoate (GuNB): An organic NLO material

Single crystals of guanidinium 4-nitrobenzoate (GuNB) were grown using solvent evaporation technique by mixing aqueous solutions of guanidine carbonate and 4-nitrobenzoic acid at ambient temperature. X-ray diffraction analysis characterized the unit cell parameters of the grown crystal and the crystal belongs to monoclinic system. The optical properties of the grown crystal have been studied by means of transmission measurements in the wavelength region between 200 and 1200 nm. The optical constants such as refractive index (n) and extinction coefficient (k) have been determined from the transmittance data. The optical band gap (E_g), the real and imaginary parts of the dielectric constant of the grown crystal was determined. Second harmonic generation (SHG) efficiency of the grown crystal has been studied using Nd:YAG laser and was measured as 3.2 times that of KDP. The low dielectric constant suggests the suitability of this compound material for NLO applications.     

Effect of ammonium acetate addition on crystal growth,spectral, thermal and optical properties of glycine single crystals

Gamma glycine single crystal is a potential organic nonlinear optical (NLO) material. It has been grown from a mixture of aqueous solutions of glycine and ammonium acetate by slow evaporation solution growth technique at room temperature for the first time. Powder X-ray diffraction studies are carried out and the results are compared. CHN analysis confirms the non-inclusion of ammonium acetate species in to the solution. FTIR studies are performed to identify the presence of various functional groups in the grown crystal. Differential scanning calorimetry analysis (DSC) was carried out to study the thermal stability and phase transition of the grown crystal. The optical analysis shows that UV cut-off of γ-glycine is at 190 nm and it has a wide transparency window. The second harmonic generation relative efficiency of the grown crystals was observed to be 1.72 times that of potassium dihydrogen orthophosphate (KDP).     

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.     

A new metal-organic nonlinear optical material: L-Asparagine Indium chloride (LAIn) for photonics application

Single crystal of l-Asparagine Indium chloride (LAIn), a new semi-organic crystal was grown by slow evaporation method with deionized water as solvent at ambient condition. The crystal structure of LAIn has been determined by single crystal X-ray diffraction and the result shows that the crystal belongs to the orthorhombic system with P2₁2₁2₁ space group. The crystalline nature of grown crystal was analyzed by powder X-ray diffraction analysis. Optical parameters, such as absorbance, transmittance and optical band gap energy were analyzed using UV–Vis NIR transmittance data at the range of 190–800?nm. The ultraviolet (UV) emission nature of the sample was established from the sharp emission peaks in photoluminescence (PL) spectrum. The photo conductivity test exhibits that the grown crystal has positive photo conductive nature. The induced surface laser damage threshold (LDT) for the grown crystal was measured using Nd:YAG laser. The nonlinear optical efficiency of the LAIn crystal was studied using modified Kurtz-Perry powder technique. The hardness, Meyer index, yield strength and elastic stiffness constant were calculated for the grown crystal using Vickers microhardness tester. The variation of dielectric constant and dielectric loss of the grown crystals as a function of frequency has been investigated at different temperatures. The melting point and thermal stability of the LAIn single crystal have been studied by thermo gravimetric analysis and differential thermal analysis (TG/DTA).     

Growth and characterization of an efficient nonlinear optical single crystal: Urea p-nitrophenol

An organic nonlinear optical single crystal of urea p-nitrophenol has been synthesized and grown by slow evaporation solution growth technique. The grown crystals were characterized by single crystal and powder X-ray diffraction analysis and it was found to be the structure of the crystal belongs to triclinic system. The various functional groups were identified by FT-IR and Raman spectral analysis. Thermal stability of the grown crystal was studied by TGA/DTA. The optical properties of the grown crystals were analyzed by UV–vis. The mechanical properties of the grown crystal were studied by Vickers microhardness measurements. Nonlinear optical property of the crystal was confirmed using the Kurtz and Perry powder technique and a study of its SHG efficiency in comparison with KDP has made.