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.     

Studies on synthesis,growth and characterization of a novel third order nonlinear optical 4-Dimethylaminopyridinium p-Toluenesulfonate single crystal

Good quality single crystals of 4-Dimethylaminopyridinium p-Toluenesulfonate (4DMAPPTS) possessing third order nonlinearity were grown by slow evaporation solution technique (SEST). Single crystal X-ray diffraction analysis reveals that 4DMAPPTS belongs to monoclinic crystal system with centrosymmetric space group P2₁/n. FT-IR spectral studies were carried out to identify the functional groups present in 4DMAPPTS. NMR spectral study confirms the molecular structure of the grown crystal. Dielectric measurements were made over a wide range of frequencies for different temperatures. The grown crystal was subjected to Vickers microhardness test to study the mechanical property. The etching studies reveal the growth pattern and dislocations present in the grown title crystal. The important optical parameters such as absorption coefficient, extinction coefficient, refractive index and optical band gap were estimated from UV–Visible spectral analysis. The negative third order nonlinear optical parameters like refractive index (n₂), absorption coefficient (β) and susceptibility (χ⁽³⁾) were estimated by Z-scan studies.     

A comparative analysis on growth aspects and characterization of novel benzophenone derivatives

The growth aspects of two benzophenone derivatives such as 4-4′ dimethylbenzophenone (4-4′ DMBP) and 4-amino benzophenone (4-ABP) were investigated based on solute–solvent interactions in the growth medium. The structural, mechanical and optical properties of the two derivatives were comparatively investigated. It was found that the 4-ABP crystal was relatively harder compared to 4-4′ DMBP. The optical transmission study showed that the 4-4′ DMBP sample has high transparency especially in the UV region as it had the cut-off wavelength of 331 nm. On the other hand, the 4-ABP crystal has relatively low transparency in the visible region with the cut-off wavelength of 400 nm. The 4-4′ DMBP sample exhibited the SHG efficiency of 1.5 times that of KDP whereas the 4-ABP sample exhibited the SHG efficiency of 161 times that of KDP. The optical properties of the derivatives were discussed in relation with the molecular structure of the materials.     

Growth, thermal, dielectric and mechanical studies of triglycine zinc chloride, a semiorganic nonlinear optical material

Triglycine zinc chloride, a semiorganic material, has been grown by slow solvent evaporation technique from a mixture of aqueous solution of glycine and zinc chloride in 2:1 molar ratio at room temperature. The grown crystal is up to the dimension of 45 × 23 × 18 mm³. Characterization of the crystals was made using single-crystal X-ray diffraction for obtaining unit cell parameters. Powder X-ray diffraction was recorded and the major peaks were indexed. Simultaneous thermogravimetric analysis and differential thermal analysis were carried out for the as grown crystals to determine the thermal stability of the crystal. The crystals were further characterized by UV-Vis-NIR transmission spectrum in the range of 200 to 1100 nm. Dielectric constant and dielectric loss measurements were carried out at different temperatures and frequencies. Mechanical studies were carried out on the as grown crystal.     

Growth and characterization of 4-dimethylamino-N-methyl 4-stilbazolium tosylate (DAST) single crystals grown by nucleation reduction method

Good quality single crystal 4-dimethylamino-N-methyl 4-stilbazolium tosylate (DAST) has been grown by novel nucleation reduction method instead of regular slope nucleation technique (SNT). The grown crystal was subjected to high resolution X-ray diffraction (HRXRD) studies, the perfection of the crystal was found to be better than the crystal grown by slope nucleation technique and slow cooling method. The UV-vis-NIR spectrum was recorded for the grown crystal and relative second harmonic generation (SHG) efficiency was investigated to explore the nonlinear optical (NLO) property. The dielectric and thermal behaviour of the crystal were also studied. The nuclear magnetic resonance (NMR) studies also performed for the identification of different modes present in the compound. The photoluminescence and mechanical were carried out and the results were discussed in detail.     

Growth and characterization of benzaldehyde 4-nitro phenyl hydrazone (BPH) single crystal: A proficient second order nonlinear optical material

The crystals (benzaldehyde 4-nitro phenyl hydrazone (BPH)) appropriate for NLO appliance were grown by the slow cooling method. The solubility and metastable zone width measurement of BPH specimen was studied. The material crystallizes in the monoclinic crystal system with noncentrosymmetric space group of Cc. The optical precision in the whole visible region was found to be excellent for non-linear optical claim. Excellence of the grown crystal is ascertained by the HRXRD and etching studies. Laser Damage Threshold and Photoluminescence studies designate that the grown crystal contains less imperfection. The mechanical behaviour of BPH sample at different temperatures was investigated to determine the hardness stability of the grown specimen. The piezoelectric temperament and the relative Second Harmonic Generation (for diverse particle sizes) of the material were also studied. The dielectric studies were executed at varied temperatures and frequencies to investigate the electrical properties. Photoconductivity measurement enumerates consummate of inducing dipoles due to strong incident radiation and also divulge the nonlinear behaviour of the material. The third order nonlinear optical properties of BPH crystals were deliberate by Z-scan method.     

Growth and characterization of a new semi-organic nonlinear optical sodium paranitrophenolate paranitrophenol dihydrate single crystal

A new semi-organic nonlinear optical sodium paranitrophenolate paranitrophenol dihydrate single crystal is grown successfully using methanol as solvent by slow evaporation technique to dimensions of 14 × 5 × 4 mm³ in a period of 7 days. The grown crystal is characterized by X-ray diffractometry and UV-Visible spectral analysis. X-ray diffraction data reveals that the crystal belongs to monoclinic system with space group C2. Optical absorption studies illustrate low absorption in the entire UV and Visible region. The second harmonic generation (SHG) efficiency of the crystal measured by Kurtz's powder technique infers that the crystal has NLO coefficient 5 times greater than that of KDP crystal. Remarkable mechanical strength with the work hardening coefficient less than 2 and thermal stability up to 120 °C of the grown crystal is reported.     

Organic nonlinear optical crystal 4-hydroxy-N-methyl 4-stilbazolium besylate synthesis and characterization

Novel organic nonlinear optical material 4-hydroxy-N-methyl 4-stilbazolium besylate has been synthesized and 7 mm × 5 mm × 3 mm size crystals were grown by slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal lattice is monoclinic. From powder X-ray diffraction analysis the diffraction planes have been indexed. Fourier transform infrared spectrum for our sample confirms the presence of functional groups in the grown crystal. Second harmonic efficiency was determined using Kurtz powder method in comparison with urea to confirm the nonlinearity of the material. The results are discussed in detail.     

Crystal growth of 2, 4, 5-Trimethoxy-4′-chlorochalcone and its characterization

An organic second-order nonlinear optical single crystal 2, 4, 5-Trimethoxy-4′-chlorochalcone was grown by slow evaporation solution growth technique. The crystal was characterized by Powder X-ray diffraction, and UV-Vis-NIR analysis. The second harmonic generation of the crystal was confirmed by using the Kurtz powder technique.     

Investigation of SR method grown 0 0 1 directed KDP single crystal and its characterization by high-resolution X-ray diffractometry (HRXRD), laser damage threshold, dielectric, thermal analysis, optical and hardness studies

0 0 1 directed potassium dihydrogen orthophosphate (KDP) single crystal was grown by Sankaranarayanan–Ramasamy (SR) method. The 0 0 1 oriented seed crystals were mounted at the bottom of the platform and the size of the crystals were 10 mm diameter, 110 mm height. Two different growths were tried, in one the crystal diameter was the ampoule's inner diameter and in the other the crystal thickness was less than the ampoule diameter. In the first case only the top four pyramidal faces were existing whereas in the second case the top four pyramidal faces and four prismatic faces were existing through out the growth. The crystals were grown using same stoichiometric solution. The results of the two growths are discussed in this paper. The grown crystals were characterized by high-resolution X-ray diffractometry (HRXRD), laser damage threshold, dielectric, thermal analysis, UV–vis spectroscopy and microhardness studies. The HRXRD analysis indicates that the crystalline perfection is excellent without having any very low angle internal structural grain boundaries. Laser damage threshold value has been determined using Nd:glass laser operating at 1054 nm. The damage threshold for the KDP crystal is greater than 4.55 GW cm⁻². The dielectric constant was higher and the dielectric loss was less in SR method grown crystal as against conventional method grown crystal. In thermal analysis, the starting of decomposition nature is similar in SR method grown KDP crystal and conventional method grown crystal. The SR method grown KDP has higher transmittance and higher hardness value compared to conventional method grown crystals.     

Crystallization and characterization of nonlinear optical material l-arginine formomaleate

The influence of mixed acids in the growth and characteristic properties of a new nonlinear optical material l-arginine formomaleate abbreviated as LAFM was examined. Single crystal X-ray diffraction analysis was used to calculate the lattice parameters of the crystals. Fourier transform infrared (FTIR) spectroscopy and thermal analysis (DTA, TGA) were performed to study the molecular vibrations and thermal behaviour of the crystals. UV-VIS spectral study shows that LAFM is transparent down to 315 nm and its second harmonic generation efficiency is 1.2 times that of KDP.     

Structure,crystalline perfection,mechanical, second harmonic generation efficiency,laser damage threshold and piezoelectric properties of bis nicotinamidium bis D-tartrate 1.25-hydrate single crystals

Bis nicotinamidium bis D-tartrate 1.25-hydrate single crystals have been grown by slow evaporation solution growth technique. Single crystal X-ray diffraction study indicates that the grown crystal crystallizes in monoclinic system with space group P2₁. Crystalline perfection of the crystal has been evaluated by high resolution X-ray diffraction technique and it reveals that the crystal is free from structural grain boundaries. Mechanical stability of the crystal has been analyzed by Vickers microhardness measurement and it exhibits reverse indentation size effect. The second harmonic generation efficiency of the grown crystal has been checked and its value is 1.24 times that of potassium dihydrogen phosphate. The surface laser damage threshold for the crystal has been analyzed and its value is 0.644 GW/cm². Piezoelectric d₃₃ co-efficient for the crystal has been examined and its value is 29.8 pC/N.     

Growth and characterization of an organic nonlinear optical material: l-alanine alaninium nitrate

l-alanine alaninium nitrate (LAAN), an organic nonlinear optical material was grown by slow evaporation technique at room temperature from its aqueous solution at pH value of 2.5. As grown single crystals were characterized for its spectral, thermal, linear and second order nonlinear optical properties. LAAN crystallizes in monoclinic system with space group P₂₁ and cell parameters a = 7.846 Å, b = 5.431 Å, c = 12.806 Å and β = 94.65°. The mode of vibrations of different molecular groups present in LAAN were identified by FTIR studies. The thermal behaviour of the crystals has been investigated using thermogravimetry (TG) and differential thermal analysis (DTA), which indicates that the material does not decompose before melting. Transmittance spectrum reveals that the crystal has a low UV cut-off of 320 nm and has a good transmittance in the entire visible region. NLO property of the crystal was confirmed by Kurtz SHG powder technique.     

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.     

Growth and characterization of Ca5(BO3)3F fiber crystals, a new nonlinear optical material for UV light generation

For the first time, Ca₅(BO₃)₃F (CBF) fiber crystals were grown by the micro-pulling down technique from LiF-based flux. Regular and transparent fibers were obtained with good optical quality. Characterization by Raman spectroscopy and EDX microprobe showed fibers compositionally homogeneous. The specific heat capacity of the fibers was measured indicating a laser damage threshold slightly lower, at room temperature, than for crystals belonging to the related rare earth calcium oxoborate family.     

Growth and characterization of some novel crystals for nonlinear optical applications

The advent of high intensity lasers coupled with the recent advances in crystal technology has led to rapid progress in the field of nonlinear optics. This article traces the history of materials development that has taken place over the past forty odd years and dwells on the current status in this important area. The materials aspect is discussed under three classes viz. inorganic, organic and semiorganic crystals. In the end, some of the crystal growth work that has been carried out in author’s laboratory is presented.     

Influence of defects on the quality and optical studies of sodium p-nitrophenolate dihydrate, a nonlinear optical material

Nonlinear optical material of sodium p-nitrophenolate dihydrate was synthesized by employing the technique of controlled evaporation and the effect of temperature on growth morphology was investigated. Single crystal XRD analysis confirms that the crystals with different morphologies have the same lattice parameters. The high-resolution X-ray diffraction curves recorded by a multicrystal X-ray diffractometer revealed the presence of very low angle tilt boundaries. The green emission band at 524 nm is due to the existence of defects on the crystal which corroborated with HRXRD studies. The wide band gap of the SPND crystals confirms the large transmittance in the visible region.     

Growth and nonlinear optical properties of Zn-doped LiB3O5 crystals

Zn-doped LiB₃O₅ (LBO) single crystals with high quality were successfully grown from the Li₂O–MoO₃–ZnF₂ ternary system by the top-seeded solution growth method. The suitable region for LBO crystal growth was investigated by growth experiments, as well as viscosity and volatility measurements, which confirmed that the optimal molar ratio of Li₂O:MoO₃:ZnF₂ was 1:1.5:0.2. The second-harmonic generation efficiency of Zn-doped LBO crystal increased by 16% compared with that of the LBO crystals grown from the MoO₃ flux. The optical homogeneity was at 10⁻⁶ cm⁻¹. Optical absorption at the critical wavelengths of 1064 nm was measured to be 15 and 18 ppm cm⁻¹, respectively.     

Optical,mechanical and transport properties of unidirectional grown l-tartaric acid bulk single crystal for non-linear optical application

Good optical quality bulk single crystal of l-tartaric acid has been grown by directional solidification crystal growth method from aqueous solution. Crystal of dimension 77 mm length and 12 mm diameter has been grown at a growth rate of 2.5 mm day⁻¹ which is the maximum size and growth rate achieved so far. The grown crystal was confirmed by powder XRD analysis and the presence of the functional groups in the crystal lattice was confirmed by Fourier transform infrared spectral analysis. Transmission spectral analysis shows that the crystal has more than 90% of transmittance in visible and near infrared region which exhibits the good optical quality of the crystal. The optical band gap was estimated to be 4.8 eV and it shows indirect optical transition. Thermal analysis shows the crystal to be thermally stable up to 172 °C and the load variation of the hardness has been explained on the basis of normal indentation size effect from microhardness study.