Synthesis, crystal growth and characterization of organic material: N-Bromosuccinimide (NBS) for NLO applications

The organic nonlinear optical crystal of N-Bromosuccinimide (NBS) was grown by slow cooling solution growth technique using methanol as solvent. Single crystal and powder X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectral analyses were carried out to confirm the NBS crystals. The ultra violet (UV)-Visible and photoluminescence spectral studies were carried out, the green band at 2.02 eV can be attributed to radiative recombination between deep donors and shallow acceptors. The second harmonic generation (SHG) behaviour of NBS was tested by Kurtz-Perry powder technique. The hardness behaviour, laser damage threshold and dielectric characteristics of NBS crystals were studied.     

Growth and characterization of 4-methyl benzene sulfonamide single crystals

Single crystals of 4-methyl benzene sulfonamide (4MBS) were successfully grown from aqueous solution by low temperature solution growth technique. The grown crystal was characterized by single crystal XRD and powder XRD methods to obtain the lattice parameters and the diffraction planes of the crystal. UV–vis–NIR absorption spectrum was used to measure the range of optical transmittance and optical band gap energy. The optical transmission range was measured as 250–1200 nm. FTIR spectral studies were carried out to identify the presence of functional groups in the grown crystal. The thermal behavior of the crystal was investigated from thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) study. The absence of SHG was noticed by Kurtz and Perry powder technique. The third order NLO behavior of the material was confirmed by measuring the nonlinear optical properties using Z-scan technique and it was found that the crystal is capable of exhibiting saturation absorption and self-defocusing performance.     

Synthesis,crystal growth,structural, spectral,thermal, mechanical,linear and nonlinear optical studies of organic single crystal 4-Iodo 4-nitrostilbene (IONS): A potential NLO material

An organic nonlinear optical material 4-Iodo 4-nitrostilbene (IONS) has been synthesized and good optical quality single crystal was grown from ethyl methyl ketone solvent by the solution growth technique. Single and powder X-ray diffraction analyses reveals that the grown crystal belongs to monoclinic crystal system with noncentrosymmetric space group ‘P2₁’ and it has good crystalline nature. Functional groups and molecular structure of the title compound were confirmed by FTIR and ¹H NMR respectively. The UV–Vis–NIR absorption study reveals no absorption in the visible region and the cut-off wavelength was found to be at 412.84 nm, TG/DTA, mass spectral analysis, photoluminescence and microhardness studies have been carried out for the grown crystals and results are discussed in detail. The second harmonic efficiency of the IONS was determined by Kurtz–Perry powder technique which reveals that the IONS crystal (3.1 V) has greater efficiency i.e., 143 times to that of KDP (21.7 mV).     

Materials synthesis,crystal growth and third nonlinear optical properties of semiorganic crystal: 4-dimethylaminopyridine lithium nitrate (DMAPLN) crystal

4-dimethylaminopyridine lithium nitrate crystal (4-DMAPLN) was synthesized by the slow evaporation solution growth technique. The titular crystal was subjected to various studies to recognize its physicochemical properties. The crystalline nature and orthorhombic crystal system were revealed by single crystal and powder XRD. FTIR spectroscopy study confirms the various modes of vibrations available in the titular crystal. Linear optical studies show the lower cut-off wavelength of 280 nm with an optical bandgap value (E_g) of 4.3 eV. The electrical behavior of the 4-DMAPLN crystal was studied using dielectric studies. The mechanical behavior of the grown crystal was analyzed using the Vicker’s microhardness study, revealing that the grown crystal belongs to the hard category. The second-order nonlinear optical (NLO) behavior of 4-DMAPLN crystal was measured using Kurtz–Perry powder techniques and it was found to be 1.17 times higher than reference KDP. Z-scan analysis reveals 4-DMAPLN is a suitable candidate for optical limiting applications.

     

Studies on the nonlinear optical single crystal: Ammonium d,l-tartrate (C4H9NO6)

The organic nonlinear optical material ammonium d,l-tartrate single crystal has been successfully grown by slow evaporation solution technique (SEST). The grown crystals were characterized by single crystal XRD and the lattice parameters have been confirmed. The structural perfection of the grown crystal was analyzed by high-resolution X-ray diffraction measurement. The optical transmittance spectrum shows that the material has a good optical transparency in the entire visible region with the UV cut-off wavelength at 234 nm. Thermogravimetric and differential scanning calorimetric measurements were performed to study the thermal properties of the grown crystal. Chemical etching studies were attempted to determine the dislocation density of the grown crystal. Mechanical behavior was assessed using Vickers hardness testing carried out on (0 0 1) crystallographic plane. The Kurtz–Perry powder SHG technique confirms the NLO property of the grown crystal and the efficiency of AMT crystal was found to be 1.3 times that of standard KDP crystal.     

Growth and characterization of hexamethylenetetramine crystals grown from solution

Organic nonlinear optical single crystals of hexamethylenetetramine (HMT; 10 × 10 × 5 mm³) were prepared by crystallization from methanol solution. The grown crystals were subjected to various characterization techniques such as single crystal XRD, powder XRD, UV-Vis and electrical studies. Single crystal XRD analysis confirmed the crystalline structure of the grown crystals. Their crystalline nature was also confirmed by powder XRD technique. The optical transmittance property was identified from UV-Vis spectrum. Dielectric measurements were performed as a function of frequency at different temperatures. DC conductivity and photoconductivity studies were also carried out for the crystal. The powder second harmonic generation efficiency (SHG) of the crystal was measured using Nd:YAG laser and the efficiency was found to be two times greater than that of potassium dihydrogen phosphate (KDP).     

Growth and characterization of l-asparagine thiourea monohydrate (LATM): A nonlinear optical single crystal

l-Asparagine thiourea monohydrate (LATM) single crystal has been successfully grown (size 15 × 10 × 3 mm³) by slow evaporation solution growth technique. To the best of our knowledge this is the first report to the literature. The grown crystal was characterized by powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopic analysis. The UV-Vis transmittance spectrum shows that the material has wide optical transparency in the entire visible region. The relative second harmonic generation was confirmed by Kurtz powder technique. The mechanical properties have been studied using Vickers microhardness tester. The birefringence of the crystal was measured in the visible region and it was found to vary with the wavelength.     

Investigation on the crystal growth and characterisation of an organometallic non linear optical crystal – Tetrathiourea mercury tetrathiocyanato manganate

An organometallic complex tetrathiourea mercury tetrathiocyanato manganate (TMTM) was synthesised by two step chemical route. The influence of pH on the solubility, stability of the growth solution and growth of TMTM single crystal was studied. The bulk crystal of dimension 2.7 cm × 0.5 cm × 0.4 cm was grown at an optimized pH value of 3.0 by solvent evaporation method using water as a solvent. The structure and the crystallinity of the grown crystal were confirmed from single crystal XRD and powder XRD studies. The presence of thiourea and thiocyanate ligand and their coordination with the metal ions are confirmed from the IR studies. The grown single crystal of TMTM shows 69% transparency over the entire range of visible region with a cut-off wavelength of 362 nm. The SHG efficiency of TMTM was found to be 0.08 time that of MMTC. The complex exhibits good thermal stability up to 205 °C and it is non-hygroscopic in nature. The surface analysis was carried out by etching studies which shows a layer growth pattern revealing the 2D nucleation growth mechanism. From the Vickers hardness studies, the work hardening coefficient and the elastic stiffness constant were calculated.     

Growth and characterization of a new NLO material: l-Glutamic acid hydro bromide [l-GluHBr]

l-(+)-Glutamic acid hydro bromide, an isomorphic salt of l-glutamic acid hydrochloride, was synthesized and the synthesis was confirmed using Fourier transform infrared analysis. Solubility of the material in water was determined. l-Glutamic acid hydro bromide crystals were grown by low temperature solution growth using the solvent evaporation technique. Single crystal X-ray diffraction studies were carried out and the cell parameters, atomic co-ordinates, bond lengths and bond angles were reported. High-resolution X-ray diffraction studies were carried out and good crystallinity for the grown crystal was observed from the diffraction curve. The grown crystals were subjected to dielectric studies. Ultraviolet-visible-near infrared spectral analysis shows good optical transmission in the visible and infrared region of the grown crystals. The second harmonic generation efficiency of l-glutamic acid hydro bromide crystal was determined using the Kurtz powder test and it was found that it had efficiency comparable with that of the potassium di-hydrogen phosphate crystal.     

Investigation on growth,structural, optical,thermal, dielectric and mechanical properties of organic l-prolinium trichloroacetate single crystals

A new organic nonlinear optical material l-prolinium trichloroacetate (l-PTCA) single crystal has been synthesized and grown by slow solvent evaporation technique at room temperature using water as solvent. Single-crystal X-ray diffractometer was utilized to measure unit cell parameters and to confirm lattice parameter. The powder X-ray diffraction pattern of the grown l-PTCA has been indexed. The modes of vibration of different molecular groups present in the sample were identified by the FTIR spectral analysis. The optical transmittance window and the lower cutoff wavelength of the l-PTCA have been identified by UV–vis–NIR studies. Thermal stability of the l-prolinium trichloroacetate was determined by TGA/DTA measurements. Dielectric measurements were carried out at various temperatures at frequency range 10–1 MHz. The mechanical properties of the grown crystals have been analyzed by Vickers microhardness method. The chemical etching studies were carried out on the grown crystals. Its SHG efficiency has been tested by Kurtz powder method.     

Laser damage threshold,antimicrobial efficacy and physicochemical properties of an organometallic L-proline lithium chloride monohydrate single crystal for NLO application and optoelectronic device fabrication

The potential metalorganic L-proline lithium chloride monohydrate single crystal was grown by slow evaporation method for evaluating optoelectronic device fabrication. From the single crystal XRD studies, the grown crystal was confirmed the molecular packing in monoclinic crystal lattice. The powder XRD data confirm the phase purity of the grown crystal. Vibrational absorption band assignments were recognized by FTIR and FT-Raman spectrum and they confirmed the presence of multiple functional groups in the grown crystal structure. Optical properties of the grown crystal were studied by using transmittance and absorption spectrum of UV–Vis–NIR analysis. The dielectric response of the grown crystal was studied in the frequency range between 50 Hz and 2 MHz for four temperature gradients. From the microhardness study, some mechanical parameters such as fracture toughness, brittleness index and yield strength were calculated. The photoluminescence activity of the grown crystal was deliberate in terms of optical peaks. The amino group participation over the optical scattering nodal regions for generating radiation absorption process to fascinate optical endurance was studied. TG/DTA curve shows that the LPLCM crystal was thermally stable up to 132 °C. The laser damage threshold value of the grown crystal was measured using multishot mode and it was found to be 7.78 GW/cm². The fractionation of the etching time prevents lattice from over etching and degradation of the mechanical properties of the grown crystal. LPLCM crystal showed higher antibacterial activity against one gram positive and one gram negative bacterial species. Second order nonlinear optical efficiency of the LPLCM crystal was studied at 1064 nm generated by a nanosecond pulsed Nd:YAG laser source.

     

Synthesis,growth, optical,spectral, thermal and dielectric studies of a new nonlinear optical material : <Emphasis Type="SmallCaps">l</Emphasis>-proline 2,4-dichlorobenzoic acid single crystal

Good quality single crystals of organic nonlinear optical material l-proline 2,4-dichlorobenzoic acid (LPDCBA) were synthesized and grown by slow evaporation technique. The lattice parameters and space group were determined using single crystal XRD analysis. The optical absorbance and the lower cut-off wavelength of the LPDCBA were identified by UV–VIS–NIR studies. The modes of vibrations of different molecular groups present in the sample were identified by the FTIR spectral analysis. Dielectric measurement of LPDCBA were carried out at different frequencies. Thermal stability of LPDCBA were determined by TGA/DTA measurements. Laser induced damage threshold study was carried out for the grown crystal using Nd:YAG laser. The second harmonic generation efficiency were found to be 1.66 times greater than that of KDP.     

Third order optical non-linear (Z-scan), birefringence,photoluminescence, mechanical and etching studies on melaminium levulinate monohydrate (MLM) single crystal for optical device applications

Z-scan studies on the grown crystal was investigated by diode-pumped Nd; YAG laser. Nonlinear refractive index (n₂) and third-order nonlinear optical susceptibility (χ³) values of MLM were found to be −1.0 × 10⁻⁸ cm²/W and 1.36 × 10⁻⁶ esu respectively. Powder X-ray diffraction analysis depicted that the crystal belongs to monoclinic system with space group P2₁/c. Birefringence study revealed the optical dispersion behavior of MLM crystal. Linear refractive index on (10-1) plane was measured by prism coupling technique and was estimated to be 1.4705. Hardness study was carried out along three different planes which exhibit hardness anisotropy of 41.11%. Meyer's index values of the grown crystal for the (10-1), (010) and (111) planes were found to be 2.39, 2.61 and 2.04 respectively. Etching studies on the prominent (10-1) growth plane was explained by two dimensional layer growth mechanisms. Photoluminescence study was performed on MLM crystal to explore its efficacy towards optical device fabrications.     

Infrared,Raman, electrical and thermal analysis of lithium sulphate monohydrate single crystals

In this work, single crystals of lithium sulphate monohydrate were grown by slow evaporation technique. Structural studies of the grown crystals were carried out by powder X-ray diffraction technique showing a monoclinic structure. Effect of temperature on the vibrational modes of different groups was observed and analyzed by Fourier transform infrared and Raman spectroscopy. The temperature dependent dielectric behaviour and ac conductivity of the grown crystals were also studied. The effect of temperature on the vibrational spectra as observed by Fourier transform infrared and Raman spectroscopy were correlated with the electrical behavior of the crystals. The relaxation studies were also undertaken using the complex-modulus M^* formalism which showed a thermally activated relaxation caused by the hopping motion of H⁺ ions in the crystal. All the observed characteristics were found to be closely related with water loss in the crystal structure. Thermal analysis of the grown crystal was carried out by using differential scanning calorimetric technique yielding various thermodynamic parameters such as ΔH, ΔS and ΔC_p. The activation energy for the dehydration step of lithium sulphate monohydrate was also evaluated by using Coats-Redfern integral method.     

Investigation on structural,optical, thermal,mechanical and dielectric properties of l-proline cadmium chloride monohydrate single crystals: An efficient NLO material

In the present work, we have grown single crystals of l-proline cadmium chloride monohydrate (LPCCM) by slow evaporation solution technique (SEST) at room temperature and recorded their live growth kinetics with the help of inverted microscope. Crystal size at various stages of growth and its corresponding morphology was also recorded. Powder X-ray diffraction (PXRD) analysis of LPCCM single crystals confirmed the orthorhombic structure. Respective values of crystallite size, strain and dislocation density have been calculated using PXRD data. Metal complex coordination of the single crystal is studied by FTIR spectroscopic. The optical properties of the grown crystals were investigated through UV–VIS spectroscopic studies and shows that the crystals have very low absorption in entire characterized wavelength range 200–800 nm. The optical band gap was calculated and found to be ∼5.6 eV. Optical constants of the material is determined by theoretical calculations. The chemical etching study was also carried out to study the density of defects in the grown crystals. The photoluminous excitation and emission spectra and thermal property by TGA/DTA curve were recorded. Further, the mechanical properties have been studied using Vicker's microhardness tester as well as many parameters such as fracture toughness (K_c), Brittleness index (B_i) and yield strength (σ_ν) are presented. Dielectric studies have been carried out with varying frequency and temperatures.     

Studies on optical and mechanical properties of new organic NLO crystal: Guanidinium 4-aminobenzoate (GuAB)

Organic nonlinear optical crystal of guanidinium 4-aminobenzoate (GuAB) has been successfully grown by slow evaporation solution growth technique. The grown crystal is up to the dimension of 36 × 8 × 6 mm³. The crystal is characterized by single crystal XRD for obtaining unit cell parameters. Optical properties of the grown crystal have been studied by means of UV–Vis–NIR transmission and absorption spectra in the range of 200 to 1000 nm. The refractive index and band gap energy of the GuAB crystal are obtained as 1.68 and 3.73 eV respectively. Mechanical hardness has been carried out on the grown crystal.     

Growth and characterization of organic material 2-hydroxypyridine single crystal by modified vertical Bridgman technique

Large size (15 mm diameter and 80 mm length) organic material 2-hydroxypyridine single crystal has been grown using the double wall ampoule with nano translation by modified vertical Bridgman technique for the first time. Material of the grown crystal was confirmed by single and powder X-ray diffraction (XRD) measurements. Fourier transform infrared (FTIR) analysis was used to identify the functional groups present in the grown crystal. High resolution X-ray diffraction (HRXRD) has been performed to analyze the crystalline perfection of the grown single crystal. The optical property of the grown crystal was analyzed by UV–vis–NIR and photoluminescence (PL) spectral measurements. The thermal characteristics of the grown crystal were analyzed by thermogravimetric (TG) and differential thermal analyses (DTA). The dielectric measurements were carried out with four different frequencies at various temperatures ranging from 308 to 373 K and the results indicate an increase in the dielectric parameters with the increase of temperature at all frequencies. The second harmonic generation (SHG) studies were used to analyze the nonlinear optical property of the grown crystal.     

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

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.     

Growth and characterization of an organic nonlinear optical crystal: Glycinium trichloroacetate

Single crystal of glycinium trichloroacetate, an organic nonlinear optic (NLO) material, has been grown by slow solvent evaporation technique at room temperature. The grown crystal was subjected to single crystal X-ray diffraction for confirming the coordination formed, and the presence of various functional groups was studied by FTIR in the range 4000–450 cm⁻¹. UV–Visible transmittance studies were performed to analyze optical transparency of the crystal and second harmonic generation was investigated to explore the NLO property of the material. Thermogravimetric and differential thermal analysis have been performed to study thermal properties of the grown crystal. Dielectric constant and dielectric loss were studied at different temperatures and frequencies. Vicker's microhardness testing was carried out on the as grown crystal to reveal the mechanical properties of the crystal. Etching studies were made on the as grown crystal to analyze the structural imperfection of the crystal.     

Synthesis,characterization, thermal and dielectric properties of pure and cadmium doped calcium hydrogen phosphate

The synthesis of pure and cadmium doped calcium hydrogen phosphate as single crystal has been accomplished by a room temperature solution growth technique viz., silica gel technique. Silica gel obtained from sodium metasilicate with a strongly acidic cation exchanger in the H-form, was used for crystal growth experiments. The nature of the grown material was established by powder X-ray diffraction (PXRD) studies, whereas from single crystal X-ray diffraction (SXRD) the crystal system comes out to be monoclinic. The stoichiometry of the grown composition was established by energy dispersive X-ray analysis (EDAX). Fourier transform infrared spectroscopic (FTIR) studies signifies the presence of phosphate (PO₄)²⁻ group and water of crystallization. Thermo gravimetrical analysis and investigations of dielectric properties were undertaken to study the thermal stability, dielectric constant and transition temperature of the grown material. Dielectric studies suggest that there is a shift in the value of transition temperature (T_c) thereby indicating relaxor behaviour of the material.