Growth and characterization of bis-glycine sodium nitrate (BGSN), a novel semi-organic nonlinear optical crystal

Single crystals of bis-glycine sodium nitrate (BGSN), a semi-organic nonlinear optical (NLO) material, have been grown by slow cooling method. Good optical quality single crystals with dimensions up to 1.6×1.6×1.0 cm³ are obtained. Using a single-crystal diffractometer, the morphology of BGSN crystal was identified. Powder X-ray diffraction confirms the crystalline nature of BGSN. The grown crystals were characterized by optical transmission spectrum (UV) and FTIR studies. The NLO property of the crystal was confirmed by Kurtz second harmonic generation (SHG) test, and the output power generated by the crystal was compared with that of KDP. The thermal stability of the crystal was studied by thermo-gravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Micro hardness study was carried out for different planes, and the anisotropy behavior of the crystal was observed.     

Synthesis,growth and characterization of organic nonlinear optical bis-glycine maleate (BGM) single crystals

A new organic compound of bis-glycine maleate was synthesized in the alkaline medium of 10% ammonium hydroxide solution. The bulk single crystals of Bis-Glycine Maleate (BGM) have been grown by slow cooling method. The grown crystals were characterized by employing single crystal and powder X-ray diffraction, Fourier transform infrared, optical absorption spectral studies and thermo gravimetric analysis. The microhardness studies confirmed that the BGM has a fairly high Vicker’s hardness number value (41 kg mm⁻²) in comparison to other organic NLO crystals. Second harmonic generation efficiency of the crystal measured by Kurtz–Perry powder method using Nd:YAG laser is found to be comparable to that of potassium dihydrogen phosphate (KDP). Frequency dependent dielectric studies were carried out along the major growth axis.     

Growth and characterization of tetramethyl ammonium tetrachloro zincate II: A ferroic crystal

Ferroic crystals of tetramethyl ammonium tetrachlorozincate (TMA-ZnCl) were grown by slow evaporation technique and the morphology of the grown crystals varies with different pH values. The compound crystallizes in orthorhombic primitive system at room temperature with non-centro symmetric space group Pmna. The grown crystals were subjected to powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet–visible–near-infrared (UV–vis–NIR) spectral studies and thermal studies. Differential scanning calorimetry (DSC) measurement confirms the existence of structural phase transition and the thermogravimetric analysis (TGA) studies reveals that the crystal is thermally stable up to 330 °C. Vicker's microhardness studies expose that the material is mechanically stable up to a load of 60 g. The laser second harmonic generation (SHG) efficiency of the grown crystal was found to be 1.3 times that of potassium dihydrogen orthophosphate (KDP) crystal.     

Ternary system Li2O–K2O–Nb2O5: Re-examination of the 30 mol% K2O isopleth and growth of fully stoichiometric potassium lithium niobate single crystals by the micro-pulling down technique

Potassium lithium niobate (KLN) single crystals have attractive properties for non-linear optical applications based on frequency conversion of laser diodes in the blue range. Especially, fully stoichiometric K₃Li₂Nb₅O₁₅ crystals would be capable of doubling a laser light in the near UV range. Using powder X-ray diffraction and DSC experiments, we have re-investigated the 30 mol% K₂O isopleth of the ternary system Li₂O–K₂O–Nb₂O₅ in order to explore the possibility of a limited existence field for this phase. From our results, it was shown that the stoichiometric KLN phase exists between 970 and 1040 °C, temperature at which it undergoes a non-congruent melting. From this conclusion, compositionally homogeneous a-axis oriented single crystals fibers of stoichiometric K₃Li₂Nb₅O₁₅ were successfully grown by the micro-pulling down technique with pulling rates in the range 0.3–0.7 mm min⁻¹. The crystal length was between 10 and 120 mm for an apparent diameter near 500 μm. The fibers, characterized by optical microscopy, X-ray diffraction and Raman spectroscopy, appeared free of macro-defects and of good quality and their stoichiometric composition was also confirmed.     

Growth and characterization of the nonlinear optical single crystal: l-lysine acetate

Single crystals of l-lysine acetate, an organic nonlinear optical (NLO) material, were grown by the controlled evaporation of its aqueous solutions. Its solubility in aqueous solution was determined gravimetrically. The grown crystals were characterized by the single-crystal diffraction, X-ray powder diffraction, Fourier transform infrared and Raman spectra. The structure analysis reveals that it belongs to the monoclinic crystallographic system, space group P2₁, with cell parameters: a=5.420(2) Å, b=7.542(4) Å, c=12.653(1) Å, β=91.73(1)°, Z=2 and V=516.8 Å³. Experiments of thermogravimetric (TG) and differential thermal analysis (DTA) were carried out to study its thermal properties. The optical behaviours, including transmission spectrum and second harmonic generation (SHG), were investigated to study its linear and NLO properties.     

Crystal growth,thermal, optical and microhardness studies of tris (thiourea) zinc sulphate - a semiorganic NLO material

Tris (thiourea) zinc sulphate (ZTS), a semiorganic nonlinear optical (NLO) material has been synthesized at 30 °C. The solubility was determined in different solvents such as water, ethanol and water mixture of ethanol (1:1). Good quality single crystals with size 10 × 8 × 6 mm³ were grown by slow evaporation technique within three weeks with approximate growth rate of 0.5 mm/day. The grown crystals have been subjected to single crystal X-ray diffraction to determine the unit cell dimensions and morphology. The TGA and DTA reveal that the material has good thermal stability. The UV-Vis spectrum shows that the material has wide optical transparency in the entire visible region. The second harmonic generation was confirmed by Kurtz powder method. The birefringence of the crystal was measured in the visible region and it was found to vary with the wavelength. The microhardness test was carried out in (100) plane and the load dependent hardness was measured. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of tris allylthiourea mercuric chloride crystals

Single crystals of tris allylthiourea mercury chloride (ATMC), a semi‐organic nonlinear optical material, have been grown from a low‐temperature solution growth technique by slow cooling method. In the present work, we have grown ATMC crystal which is a new nonlinear optical material (NLO) having high optical quality and its second harmonic generation (SHG) efficiency is thrice that of Urea. The grown crystals have also been subjected to various characterization studies like X‐ray diffraction, UV‐VIS, FT‐IR and TGA‐DTA. X‐ray powder diffraction study confirmed the crystal structure of ATMC, UV‐VIS /FT‐IR spectral analysis showed the crystal has good optical transmission in the entire visible region and TGA‐DTA studies showed the thermal properties and complex degradation of ATMC crystal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Nucleation, growth and characterization of L-tartaric acid—nicotinamide NLO crystals

The solubility, metastable zone width and nucleation parameters of organic nonlinear optical material L-tartaric acid–nicotinamide (LTN) have been determined. The crystals of LTN are grown by the slow cooling method. The grown crystals are morphologically interpreted. The crystalline powder of the grown crystals has been examined by X-ray diffraction and thermogravimetric analysis. The different modes of vibrations present in the crystal are identified by the Fourier infrared spectroscopy analysis. The powder SHG efficiency of LTN is comparable with that of KDP.     

Growth and characterization of a novel NLO crystal bis-glycine hydrogen chloride (BGHC)

Single crystals of bis-glycine hydrogen chloride (BGHC), a semiorganic nonlinear optical (NLO) material, have been grown by slow solvent evaporation technique. Good optical quality single crystals with dimensions up to 33×5×5 mm³ are obtained. The crystals are characterized by optical transmission spectrum, FTIR and X-ray diffraction studies. The thermal stability of the crystal is studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The second harmonic generation (SHG) efficiency of BGHC was found to be 5.6 times that of KDP. The laser damage threshold values studied in single shot mode indicates that BGHC crystal possesses a fairly high value of 9.8 GW/cm² and thus the NLO studies confirmed the superiority of BGHC over KDP and urea crystals. The dielectric constant of the crystal was studied as a function of frequency and the results are discussed.     

Growth and characterization of organic material 4-nitrobenzaldehyde single crystal using modified vertical Bridgman technique

The organic material 4-nitrobenzaldehyde single crystal has been grown using the single wall ampoule with nano-translation by modified vertical Bridgman technique. The grown crystal was confirmed by single and powder X-ray diffraction (XRD). Fourier transform infrared (FTIR) analysis was used to identify the functional groups present in the grown 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 and the results indicate an increase in dielectric and conductivity parameters with the increase of temperature at all frequencies. The microhardness measurements were used to analyze the mechanical property of the grown crystal.     

Nucleation kinetics and growth of nonlinear optical bis (dimethyl sulfoxide) manganese mercury thiocyanate single crystals

Nonlinear optical (NLO) material of bis (dimethyl sulfoxide) manganese mercury thiocyanate (MMTD) was synthesized by two step reaction method. The solubility and metastable zonewidth were experimentally determined in order to optimize the growth parameters. Bulk crystals of MMTD were grown by slow cooling and slow evaporation methods. The structure of the grown crystal was confirmed by X‐ray diffraction analysis. Presence of functional groups and the coordination of Lewis base ligand of dimethyl sulfoxide (DMSO) were confirmed by FT‐IR analysis. Optical transparency of the grown crystals was studied by UV‐Vis spectroscopy. Nonlinear optical property of the grown crystal was confirmed by Kurtz powder method. Etching studies reveal the formation of triangular hillock etch patterns, indicative of 2D nucleation mechanism. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure,spectroscopic studies and non‐linear optical properties of 2‐amino‐3‐nitropyridinium trichloroacetate

A new quadratic nonlinear optical crystal, 2‐amino‐3‐nitropyridinium trichloroacetate (2A3NPTCA), was synthesized and the single crystals were grown by slow evaporation method at room temperature. Single crystal X‐ray diffraction and powder X‐ray diffraction experiments were carried out in order to confirm the structure and crystalline nature of 2A3NPTCA crystal. The chemical bonding and various functional groups present in the 2A3NPTCA were identified from FT‐IR spectrum. The UV–visible–NIR transmission spectrum shows that it is suitable for frequency‐converting in the wavelength region of 431–1200 nm. Thermogravimetric (TG) and differential thermal analysis (DTA) were carried out to characterize the thermal behaviors of the grown crystals. Kurtz and Perry powder method for second harmonic generation (SHG) measurements demonstrate that 2A3NPTCA is a phase matching material and its nonlinear optical efficiency is two times that of KDP. All the above results suggest that 2A3NPTCA is a potential candidate of NLO material.     

Unidirectional seeded single crystal growth from solution of benzophenone

A novel crystal growth method has been established for the growth of single crystal with selective orientation at room temperature. Using volatile solvent, the saturated solution containing the material to be crystallized was taken in an ampoule and allowed to crystallize by slow solvent evaporation assisted with a ring heater. The orientation of the growing crystal was imposed by means of a seed fixed at the bottom of the ampoule. By selecting a suitable ring heater voltage and by controlling the ring heater voltage, nucleation and the growth rate of the crystal were controlled more effectively. By employing this novel method, benzophenone single crystal ingots of diameters 10 and 20 mm and length more than 50 mm were successfully grown using xylene as solvent. The ease in scaling up of diameter from 10 to 20 mm shows the vital advantage of this technique. It was possible to achieve solute–crystal conversion efficiency of 100 percent. The grown benzophenone crystal was characterized by FTIR, TG and DTA, powder X-ray diffraction, X-ray rocking curve, optical transmission study and powder SHG measurement. The results show that the crystal quality is at least as good as the quality of the crystal grown by other known methods. Also, microbial growth was naturally avoided in this method, as the fresh solution is constantly made available for the growing crystal.     

Synthesis, growth and characterization of nonlinear optical crystal: l-tyrosine hydrobromide

l-tyrosine hydrobromide (l-THB) a semi organic nonlinear optical material with molecular formula C₉H₁₂NO₃Br has been synthesized at ambient temperature. Spectral, thermal and optical techniques have been employed to characterize the new material. The solubility of l-THB at varying temperatures was determined in different concentrations of hydrobromic acid. Bulk single crystals of size 15×7×4 mm³ of l-THB were grown by slow evaporation method at constant temperature. Powder X-ray diffraction pattern of the grown l-THB has been indexed. Functional groups present in the sample were identified by FTIR spectral analysis. Chemical composition of the synthesized material was confirmed by carrying out CHN analysis. Thermal stability of l-THB was determined from TGA/DTA and DSC response curves. Mechanical hardness of the grown crystal l-THB was determined and Vickers hardness number was calculated. The Kurtz powder second harmonic generation test shows that the compound is a potential candidate for optical second harmonic generation. The optical transparency range and the lower cut-off of UV transmission were identified from the recorded UV-vis spectrum of l-THB. The optical energy gap of l-THB is 3 eV.     

Growth and characterization of a novel organic NLO crystal: 4 – ethoxy benzaldehyde – n – methyl 4 – stilbazolium tosylate

The organic material 4‐Ethoxybenzaldehyde‐N‐methyl 4‐Stilbazolium Tosylate (EBST) is a new NLO material and new derivative in Stilbazolium Tosylate family. In this work we synthesized the EBST, the derivative of DAST. By slow evaporation method, we have grown the EBST crystal. Powder XRD confirms the crystalline property, the lattice parameters are calculated from single crystal XRD data and the molecular structure also revealed. The crystal system is found as monoclinic. The crystalline perfection is assessed by the high‐resolution X‐ray diffractometry. A single and reasonably sharp peak observed in the diffraction curve indicates that the quality of the crystal is quite good without having any internal structural grain boundaries. The FTIR and proton NMR study confirm the presence of functional groups. From the UV – Vis Far IR absorption spectra the good transparency is revealed. The Kurtz Perry SHG test confirms the NLO property of the EBST crystal grown and it is 11 times greater than urea. The melting point of the grown crystal is found to be 237°C from the DSC curve. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis, growth of organic nonlinear optical crystal: Semicarbazone of 2-amino-5-chloro-benzophenone (S2A5CB) and its characterisation

A new organic crystal of semicarbazone of 2–amino–5–chloro–benzophenone has been grown as a single crystal by slow evaporation solution growth technique for the first time in the literature. The grown crystal has been characterised by proton nuclear magnetic resonance spectral analysis and single crystal and powder X-ray diffraction studies. Functional groups of the crystallised molecules were confirmed by FT-IR and FT-Raman analyses. Mechanical strength of the crystals was studied by microhardness test. Optical transparency of the grown crystals has been studied by UV-Visible spectra. The second harmonic generation property of the compound was analysed.     

Growth,optical and thermal studies of nonlinear optical L‐arginine perchlorate single crystals

A potentially useful semiorganic nonlinear optical (NLO) material, L‐arginine perchlorate, has been synthesized and bulk crystals have been grown by slow cooling technique. The grown crystals were characterized by single crystal X‐ray diffraction, UV‐Vis‐NIR spectroscopy, FT‐IR, thermal analysis and SHG measurements. The grown crystals were thermally stable upto 153°C and exhibit SHG efficiency of about 0.17 with respect of Urea. The etching studies have been carried out on the grown crystal. LAPC has good optical transmission not only in the visible range, however, also in the near UV part of the spectra and hence it is a potential material for nonlinear frequency conversion. The refractive index was measured by the Brewster's angle method. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal growth of PbFCl by modified Bridgman method

Lead fluoride chloride (PbFCl) crystal was grown by modified Bridgman method. The result of X-ray powder diffraction pattern (XRD) was well accordant with the data of JCPDS card. The transmittance spectrum was first reported without absorption band from 270 to 800 nm. Three emission bands were first observed at room temperature when excited by ultraviolet light.     

Growth and characterization of thiourea mixed cadmium – lead chloride – a nonlinear optical crystal

Nonlinear optical (NLO) crystal of thiourea mixed cadmium–lead chloride dihydrate Cd[(PbCl₃)(NH₂CSNH₂)].2H₂O (TCCPC) have been grown in solution by slow evaporation technique at room temperature. The powder X‐ray diffraction pattern has been recorded and indexed. The UV‐Vis‐NIR transmittance and FT‐IR spectrum have been recorded in the range 200‐1090 nm and 400‐4000 cm^‐1, respectively. The lower cut‐off wavelength is 280 nm in the UV region, which is higher than that of pure Cd(PbCl₃) (CCPC) crystal. The presence of functional groups has been confirmed by FT‐IR analysis. The TCCPC crystal was characterized by SEM and EDX spectrum. The second harmonic generation (SHG) of the thiourea mixed cadmium–lead chloride (TCCPC) crystal is demonstrated by the Kurtz Perry method using Nd:YAG laser and the results confirm that the grown crystal is roughly three times more efficient than ADP. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of l-Tartaric acid,an NLO material

Single crystals of l-Tartaric acid (C₄H₆O₆), an organic nonlinear optical (NLO) material, have been grown by hanging seed solution and submerged seed solution techniques at room temperature. The crystal system has been confirmed from the single crystal X-ray diffraction analysis. The crystalline perfection was evaluated using high-resolution X-ray diffractometry (HRXRD). From this analysis, it was found that the quality of the crystal is quite good. The functional groups were identified using FTIR spectroscopy. UV–vis–NIR spectrum showed the absence of absorption in the wavelength region of 220–900 nm. The second harmonic generation efficiency is 89% compared to that of standard potassium dihydrogen phosphate (KDP). The laser damage threshold value is much higher than that of KDP and closer to that of β-barium borate.