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.     

Growth and characterization of new semi-organic l-proline strontium chloride monohydrate single crystals

The present communication deals with the synthesis, single crystal growth and characterization of a new nonlinear optical material l-proline strontium chloride monohydrate (l-PSCM). Single crystals have been grown using the slow solvent evaporation technique. Single crystal XRD analysis confirmed that the crystal belongs to the orthorhombic structure with lattice parameter a=6.6966(3) Å, b=12.4530(5) Å, c=15.2432(5) Å and space group P2₁2₁2₁. Presence of various functional groups in l-PSCM and protonation of the ions were confirmed by Fourier transform infrared spectroscopy (FT-IR) analysis. The melting point of the single crystal was found to be 126 °C using DSC. Ultraviolet-visible spectral analyses showed that the crystal has low UV cut-off at 226 nm combined with very good transparency of 90% in a wide range. The optical band gap was estimated to be 5.82 eV. Capacitance and dielectric-loss measurements were carried out at different temperatures in the frequency range 1 kHz-2 MHz. The dielectric constant and loss factor were found to be 21 and 0.03 at 1 kHz at room temperature, respectively. Microhardness mechanical studies show that hardness number (H_v) increases with load for l-PSCM single crystals the by Vickers microhardness method. Second harmonic generation (SHG) efficiency was found to be 0.078 times the value of KDP.     

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.     

Synthesis and characterization of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) single crystal

Single crystals of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) were grown by a slow evaporation solution growth technique at room temperature. This is the first report in the literature on the crystallization of SPH3MA. The cell parameters of the grown crystals were estimated by single crystal X-ray diffraction analysis. The various planes of reflection were identified from the XRD powder pattern. The presence of functional groups was identified from FTIR and ¹H NMR. The results were found to be in accordance with the structure of the crystal. The formation of charge transfer complex was confirmed by UV-vis-NIR spectroscopy. The thermal stability of the grown crystal was studied by thermal analysis.     

Synthesis,crystal growth and characterization of organic NLO material: 4-Bromo-4′-hydroxybenzylidene aniline

One of the novel benzylidene aniline derivatives, 4-bromo-4′-hydroxybenzylidene aniline (BHBA) was synthesized and single crystal of BHBA was grown from solution following slow evaporation method at room temperature. Unit cell parameters of the grown crystal were determined from single crystal X-ray diffraction studies. Functional groups of BHBA were identified from Fourier transform infrared spectral study. UV–vis-NIR analysis of BHBA showed that the crystal is transparent between wavelengths 400 and 1100 nm. Thermal stability of the title compound was examined by thermogravimetric and differential scanning calorimetric studies. Fluorescence spectrum of the grown crystal recorded using spectrofluorometer shows emission peak at 450 nm. The second harmonic generation efficiency of BHBA estimated by Nd:YAG pulsed laser employing the Kurtz powder technique is ∼1.3 times that of potassium dihydrogen orthophosphate. Microhardness studies reveal that BHBA possesses high Vickers hardness value. The dielectric measurements were carried out at different temperatures and frequencies and the results are discussed.     

Synthesis,growth and characterization of non-linear optical material: l-Tryptophan p-nitrophenol (LTPNP) single crystal

A new nonlinear optical organic crystal l-tryptophan p-nitrophenol (LTPNP) of dimension 19 mm × 2 mm × 1.5 mm has been grown from an aqueous solution for the first time by slow evaporation technique at ambient temperature. The crystal structure of LTPNP was confirmed by single crystal X-ray diffraction. LTPNP crystallizes in non-centrosymmetric monoclinic system with space group P₂₁. The recorded FTIR spectrum confirms the presence of various functional groups in the grown crystal and confirms the formation of LTPNP. Thermal stability and melting temperature of the LTPNP crystal were identified from TG/DTA analysis. The optical absorption study confirms the suitability of the crystal for device applications. LTPNP exhibits SHG efficiency over 1.7 orders of magnitude higher than that of urea and 4 orders of magnitude higher than that of KDP.     

Synthesis of ultrafine single crystals and nanostructured coatings of indium oxide from solution precursor

Indium oxide (In₂O₃) has been widely used in sensors, solar cells and microelectronics. There are several techniques available for making In₂O₃ such as vapor, electrochemical and atomic layer deposition, which are not only expensive but also time consuming processes. In this study, an inexpensive and straightforward synthesis approach is being presented to make micron/submicron size single crystals as well as nanostructured adherent coatings of In₂O₃ using Indium Chloride (InCl₃) powders and InCl₃ solution precursor. Both the powders and the solution precursor were calcined in a furnace to obtain the crystals; however, the liquid precursor was also treated by a DC plasma jet to obtain the nanostructured coatings. The phase transformations during thermal decomposition of InCl₃ powders and solution precursor were investigated via differential scanning calorimetry studies. The phase structure and crystallinity of the crystals and coatings were confirmed by X-ray diffraction. Microstructural characterization of the crystals and coatings was done by scanning electron microscopy, transmission electron microscopy and atomic force microscopy techniques. Size of the crystals was observed to be dependent on the heating schemes adapted during calcination. Solution precursor plasma sprayed In₂O₃ coatings showed porosity and ultrafine particulates with grain size ranging between 10 and 75 nm. Resistivity was determined to be ∼0.553 ± 0.337 kΩ cm. Optical transmittance of In₂O₃ coatings was ∼60-78% in the visible region and it was observed to decrease with increasing the number passes or the thickness of the coatings. Based on the optical transmission data, direct band gap of 3.57 eV was determined.     

Synthesis, growth and characterization of novel semiorganic nonlinear optical potassium boro-succinate (KBS) single crystals

Single crystals of novel semiorganic material, potassium boro-succinate (KBS) 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. 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. The thermal stability of the KBS crystal was studied by using TG/DTA analysis. The dielectric constant and loss were studied as a function of frequency. Nonlinear optical properties (NLO) test was performed by using Kurtz powder technique.     

Growth and characterization of potassium halides mixed l-arginine phosphate monohydrate semi organic nonlinear optical single crystals

Single crystals of pure and potassium halides additive mixed l-arginine phosphate monohydrate have been grown with good optical quality by slow temperature reduction method. Microbial growth aspects and coloration have been studied on the growth solutions. In addition to that the structural properties have been studied by powder X-ray diffraction method and Fourier transform infrared spectral analyses for the grown crystals. Thermal stability of the grown crystals were studied by thermo gravimetric (TG) and differential thermal analyses (DTA) and found that the grown crystals are suitable for device fabrication for frequency conversion applications.     

Growth and characterization of bis(thiourea) zinc carbonate (BTZC) a new nonlinear optical material by solution growth slow evaporation technique

A new semi-organic nonlinear optical bis(thiourea) zinc carbonate (BTZC) material has been synthesized. BTZC single crystals were grown from aqueous solution by slow evaporation method. The grown crystals were characterized by single crystal X-ray diffraction (XRD), powder XRD, FTIR, UV–visible, thermal, and second harmonic generation (SHG) analysis. Single crystal XRD study has been carried out to identify the lattice parameters. FTIR studies confirm the functional groups present in the grown crystal. Optical transmission studies have confirmed that the grown crystal is highly transparent. Thermo gravimetric and differential thermal analyses reveal the good thermal stability of the material. The SHG conversion efficiency of BTZC was determined using Kurtz powder technique and found 1.3 times more than that of KDP.     

Synthesis, growth and characterization of a new derivative 4-ethoxy-N-methyl-4-stilbazolium besylate monohydrate single crystal

A new organic material 4-ethoxy-N-methyl-4-stilbazolium besylate monohydrate, a derivative in the stilbazolium family, known for efficient nonlinear optical materials, has been synthesized for the first time. Employing the slow evaporation technique, optically transparent good quality single crystals of size 15 mm×10 mm×5 mm were grown from methanol. The cell dimensions obtained by single crystal X-ray diffraction studies reveal that the crystal belongs to the monoclinic system. Functional groups of the grown crystal were identified from FTIR and NMR spectral analysis. UV−vis−NIR studies show that the crystal is transparent in the wavelength range 460-1100 nm. The thermal stability of the compound was determined by thermal analyses of the specimen.     

Synthesis,growth and characterization of an organometallic complex tri-allylthiourea cadmium bromide single crystals

Allylthiourea cadmium bromide (ATCB) is a promising organometallic second order nonlinear optical material. ATCB was synthesized in Millipore water and single crystals of ATCB were grown by isothermal solvent evaporation as well as by conventional temperature lowering methods. Crystal structure of the as grown ATCB was analyzed by single crystal X-ray diffraction and also by powder X-ray diffraction pattern. Structural perfection of the as grown single crystal was studied through multicrystal X-ray diffraction analysis. The nature of co-ordination and the functional groups present were investigated by the Fourier transform infrared spectrum. The melting point of the crystal was studied through differential scanning calorimetric analysis. The optical absorption spectrum of the as grown crystal exhibits the lower cut-off (295 nm) with the wide transparent UV–VIS–NIR wave band. The SHG property was identified by Kurt’z powder technique. The linear refractive index of the as grown crystal was measured for different laser wavelengths. The reverse indentation size effect for the as grown crystal was confirmed from the mechanical studies. Growth mechanism and surface features of the as grown single crystals were analyzed by chemical etching analysis.     

Synthesis,growth and characterization of L-proline dimercuricchloride single crystals for frequency conversion applications

A semi-organic nonlinear optical L-proline dimercuricchloride (LPDMC) material has been synthesized. LPDMC single crystals were grown from aqueous solution by a slow cooling method. Good quality single crystals of size 19×6×3 mm³ have been grown over a period of 3 weeks. The grown crystals have been subjected to single crystal X-ray diffraction analysis to determine the cell parameters. The title compound crystallizes in the triclinic system with a noncentrosymmetric space group P1 and with unit-cell parameters a=7.2742(4) Å, b=9.4472(5) Å, c=10.4767(6) Å, α=108.621(3)^°, β=107.260(2)^°, γ=97.353(2)^° and volume=631.51(6) Å³. Optical and dielectric properties of the crystals have been studied. The thermal stability of the crystals was determined by thermogravimetric analysis/differential thermal analysis. The second harmonic generation efficiency of the crystals was obtained by the classical powder technique using a Nd:YAG laser and it is found to be 2.5 times that of potassium dihydrogen phosphate.     

Synthesis, characterization, and applications of shaped single crystals

In this paper we shall review techniques for the growth of single crystal, mostly of insulating material, which are shaped during the growth process. In particular, we shall focus on the growth of single-crystal fibers of optically activated materials; the emphasis will be placed on the so-called Laser Heated Pedestal Growth (LHPG) method of pulling crystalline fibers. LHPG offers a number of logistical advantages which can be exploited as a tool for materials research. Progress in the synthesis of materials using LHPG is described, as are spectroscopic techniques which are employed in characterizing the optical and physical properties of the crystal fibers obtained by this method. Fiz. Tverd. Tela (St. Petersburg) 41, 770–773 (May 1999) Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor.     

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.     

Synthesis,growth and characterization of l-asparagine cadmium bromide: A novel semiorganic nonlinear optical single crystal

Single crystal of l-asparagine cadmium bromide (LACB), a semiorganic nonlinear optical material was grown by solution growth method at the room temperature. 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 was belongs to orthorhombic system. The UV–vis–NIR spectroscopic study revealed that the crystal has good optical transparency and lower cut off wavelength was found to be 230 nm. The presence of functional group was identified by Fourier transform infrared (FTIR) analysis. The chemical composition was confirmed by elemental analysis. The mechanical strength was studied and found to be 100 g by using Vicker's micro hardness tester. The thermal stability was found to be 218 °C by using TGA and DTA analysis. The second harmonic generation efficiency was carried out by using Kurtz–Perry powder technique and it was found to be 3.4 times higher than KDP crystal.     

Synthesis,growth of single crystals and their characterization: l-Alaninium maleate (LAM)

In recent days amino acid single crystals are gaining importance due to good optical behavior. The title compound consists of l-alanine; an amino acid and maleic acid; an aromatic organic compound. It has been successfully synthesized and the single crystal has been grown by slow evaporation solution growth. The grown single crystal has been characterized by powder X-ray diffraction (PXRD) analysis and FTIR measurements. The crystalline perfection was examined by high-resolution X-ray diffraction (HRXRD) technique and found that the specimen quality is quite good. Optical behavior has been assessed by UV–Vis analysis and found that there is no absorption in the entire visible region. The relative second harmonic generation (SHG) efficiency measurement reveals that the incorporation of maleic acid to l-alanine leads to increase its value of SHG. The mechanical behavior and the thermal analysis have been carried out using Vickers microhardness and TG/DTA measurements respectively. Its hyperpolarizability was estimated by density functional theory (DFT).     

Growth of single crystals of copper and their thermal profile estimation

Copper crystals have been grown by Czochralski technique in a 6-bar argon gas environment. X-ray analysis shows that these are single crystals and are strain-free. A slight pressure environment that is truly hydrostatic seems to improve the quality of the crystals. Thermal profile estimation results show that the values of temperature which decrease upto the neck region are same in magnitude as those measured during the experiments and that necking improves the thermal profile and, consequently, the crystal quality. No facet formation has been observed in these crystals.     

Conditions for growth of columnar and filamentary crystals

The computer model of the initial stage of condensation processes is developed. The stochastic processes of adsorption, surface diffusion, and desorption occur on the 70×70 lattice of adsorption vacancies. The model was tested by an example close to water vapor sorption on a conventional crystal surface. Computed results demonstrate the processes of nucleation, growth of crystals, and developed condensation. Computations were carried out for various adsorption energies. Results showed that with decreasing energy of adsorption the character and rate of nucleation and subsequent condensation vary. With decreasing energy of adsorption the probability of nucleation of islets on substrate reduces, the filling of the next atomic layers on islets occurs earlier than the filling of the substrate, the growth rate of islets in height increases as compared to condensation of a continuous film, and the growth rate of area of islets decreases. There is a typical energy of adsorption at which the growth rate of islets in height reaches its maximum. At a further drop of adsorption energy, there is a growth of islets only in height, the growth rate, however, reduces. The phenomena revealed in computations illustrate the mechanism of origin of columnar and filamentary crystals.