Growth and characterization of semiorganic NLO crystal of l-glutamic acid hydrochlorobromide (LGHCB)

Single crystals of nonlinear optical material l-glutamic acid hydrochlorobromide (LGHCB) were grown by slow evaporation technique from its aqueous solution. Optically good quality crystals of dimension 20 × 10 × 2 mm³ were obtained. The lattice parameters for the grown crystals were determined using single crystal X-ray diffraction study. The LGHCB crystal belongs to non-centrosymmetric P2₁2₁2₁ space group. The crystal structure was resolved by direct method and refined by full matrix least-square method using SHELXL-97. Using the powder X-ray diffraction study, the crystallinity of the grown crystal was confirmed and the diffraction peaks are indexed. From Fourier transform infrared spectroscopy study, the various functional groups present in LGHCB crystal were elucidated. The UV–Vis-NIR absorption spectrum was recorded in the range of 200–2,000 nm, and the lower cut off wavelength is ~235 nm. Optical band gap of the grown crystal was found to be 5.22 eV. Thermal properties of LGHCB crystal were studied by thermogravimetric analysis and derivative thermogravimetric analysis. The second harmonic generation efficiency of LGHCB crystal was confirmed by Kurtz’s powder technique.     

Studies on the characterisation of l-proline thiourea monohydrate nonlinear optical single crystal

l-Proline thiourea monohydrate nonlinear optical single crystal of size 65 × 15 mm² was grown by slow evaporation technique at room temperature. The grown crystal was characterised by single crystal XRD, absorption spectrum, FTIR, EDAX, Vicker’s microhardness test, DSC, dielectric and photoconductivity studies. Second harmonic generation efficiency of the grown crystal makes it a higher order second harmonic material with good conversion efficiency. The reported crystal is an efficient nonlinear optical material with good optical transparency, thermal, mechanical strength and dielectric property.     

Growth, optical, thermal, and conductivity behavior of nonlinear optical single crystals of CdHg(SCN)4(CH3OC2H5O)

In this study, organometallic nonlinear optical single crystal of Cadmium mercury thiocyanate glycol monomethyl ether was grown by slow evaporation technique at room temperature. The grown crystal was confirmed by single crystal XRD and FT-IR analysis. Optical and thermal properties of the sample were investigated by UV–Vis–NIR, TG–DTA and DSC technique. Using Tauc’s relation, the band gap of the crystal was estimated as 3.99 eV. The thermal studies confirm that the CMTG is thermally stable up to 105 °C. Photoluminescence and ac & dc conductivity measurements of the sample were also carried out and reported for the first time. The PL analysis confirms the suitability of the material for application in the blue–green region. The temperature dependences of ac & dc conductivities of CMTG were investigated, and the activation energies were found to be 0.098 and 0.045 eV, respectively. The SHG efficiency measurement confirms that the NLO efficiency of CMTG is nearly three times more efficient than urea.     

Synthesis, growth, structural, spectroscopic and optical studies of a new semiorganic nonlinear optical crystal: L-valine hydrochloride

Single crystals of a new semiorganic nonlinear optical (NLO) material, L-valine hydrochloride (LVHCl), having dimensions up to 20 mm x 6 mm x 4 mm have been grown by slow evaporation solution growth technique. Single crystal X-ray diffraction studies confirm that the grown crystal belongs to the monoclinic system. The functional groups presented in the crystal were confirmed by Fourier transform infrared (FTIR) technique. Optical transmission spectrum shows very low absorption in the entire visible region. Differential thermal and thermogravimetric analyses confirmed that the crystal is stable up to 211 degrees C. The powder second harmonic generation (SHG) efficiency of LVHCl is 1.7 times efficient as potassium dihydrogen phosphate (KDP).     

Crystal growth, structural, thermal, and dielectric characterization of Tutton salt (NH4)2Fe(SO4)2·6H2O crystals

A good quality single crystal of Tutton salt, (NH₄)₂Fe(SO₄)₂·6H₂O, with dimensions 6 × 7 × 3 mm³ was successfully grown by the slow evaporation growth technique at ambient temperature. The grown crystal was subjected to single crystal X-ray diffraction study which confirms that the grown crystal is monoclinic in nature with the space group P2₁/c. Optical absorption spectrum reveals that the grown crystal has good optical transparency in the entire visible region and its energy band gap was determined. The thermal behavior of the grown crystal was investigated by thermogravimetric and differential thermal analysis. The dielectric measurements were carried out to determine the dielectric behavior of the crystal.     

Investigation on structural,spectral, and thermal properties of l-histidinium glutarate monohydrate (LHG)

l-histidinium glutarate monohydrate, an organic nonlinear optical crystal has been successfully grown from deionized water by slow solvent evaporation method at room temperature. Crystal structure and its lattice parameters were identified by single-crystal X-ray diffraction technique. Crystalline perfection of the grown crystal was studied by high-resolution X-ray diffraction rocking curve measurements by employing a multicrystal X-ray diffractometer. FT-IR and FT-Raman spectral studies were employed to identify the presence of various functional groups and mode of vibrations in the crystal. Thermal behavior of the crystal was studied by TG–DTA, TG–DTG, and DSC analyses. Optical absorption of the crystal in the wavelength region 200–1,000 nm was studied by UV–Vis–NIR spectral analysis. Kurtz and Perry powder technique was employed to find the second harmonic generation efficiency of the crystal.     

Growth, structural, optical and thermal properties of gamma-glycine crystal

Single crystals of gamma-glycine were grown from a mixture of glycine, water and lithium bromide. Single crystal X-ray diffraction analysis confirmed the growth of gamma-glycine phase. Presence of various functional groups of gamma-glycine was identified by FTIR spectrum. Optical absorbance spectrum recorded in the wavelength range of UV-vis-NIR revealed that this crystal has good optical transparency in the range 250-1500 nm. Vickers microhardness values were estimated on the prominent (100) face. Thermogravimetric and differential scanning calorimetric analyses were carried out to study the thermal properties of gamma-glycine. Second harmonic generation efficiency of the crystal measured by Kurtz's powder method using Nd:YAG laser is about three times that of KDP.     

Crystal growth, spectral, optical, and thermal characterization of glycyl-l-alanine hydrochloride (GLAH) single crystal

A new semi-organic nonlinear optical material glycyl-l-alanine hydrochloride (GLAH) was grown successfully by slow evaporation solution growth method. The solubility of GLAH was estimated for a wide range of temperatures. Large size single crystal of size 15?×?9?×?6?mm³ was grown at room temperature. The grown crystal was subjected to single crystal X-ray diffraction study which confirms that the grown crystal is monoclinic in nature with the space group P2₁. The molecular weight of the title compound was estimated by mass spectrometry. Functional groups and the modes of vibrations were identified by FT-IR spectral analysis. The UV?Cvisible spectral study reveals that the percentage of optical transmission of the sample is very high in the entire visible and UV regions. The second harmonic generation of the crystal was confirmed by the Kurtz and Perry technique. The hardness of the sample was tested by microhardness test which shows that the grown crystal belongs to the soft category of materials. The thermal stability of the compound was studied by TG?CDTA analyses which indicate that the crystal is thermally stable up to 248.6?°C.     

Spectroscopic and thermal studies of γ-glycine crystal grown from potassium bromide for optoelectronic applications

Single crystals of an organic nonlinear optical material γ-glycine have been synthesized by slow evaporation technique from aqueous solutions of α-glycine and potassium bromide at room temperature. Single crystal X-ray diffraction analysis confirmed the growth of γ phase of glycine. The powder X-ray diffraction of the grown crystal was recorded and indexed. Functional groups present in the sample were identified by FTIR spectral analysis. The optical absorption studies show that the UV cut-off wavelength of γ-glycine is at 238 nm and has a wide transparency window. The thermal characteristics of the grown crystal were determined by thermogravimetric and differential thermal analysis (TG/DTA), which show the thermal stability of the grown crystals. The powder second harmonic generation (SHG) efficiency of γ-glycine crystals was measured by Kurtz and Perry powder technique using Nd:YAG laser and it was found to be 2.56 times that of potassium dihydrogen phosphate (KDP) crystals.     

Thermal, mechanical, and optical studies of NaBr-added l-alanine crystal

The 1:1 adduct of l-Alanine and sodium bromide (l-ANaBr) crystal has been grown from aqueous solution by a slow evaporation technique. l-alanine and sodium bromide were used in the ratio 1:1 for synthesis. Characterizations were carried out to study the thermal, optical, and mechanical properties of the grown crystal. Single-crystal X- ray diffraction analysis shows that the grown crystal belongs to the monoclinic system. The crystalline nature and its various planes of reflections were observed by powder XRD analysis. Thermal studies reveal that the crystal is stable up to 113.37 °C. The chemical compositions of the grown crystal were determined by FT-IR spectral analysis. The transmittance, absorption, and reflection spectrum of l-ANaBr crystal studied using a UV–Vis spectrometer indicates that the crystal has good optical transparency. The mechanical property of the grown crystal studied using Vickers microhardness measurement reveals that the crystal is a soft material.     

Crystal growth and characterization of γ-glycine grown from potassium fluoride for photonic applications

Single crystals of γ-glycine, an organic nonlinear optical material have been synthesized in the presence of potassium fluoride (KF) by slow evaporation technique at ambient temperature. The size of the grown crystal is up to the dimension of 12 mm×10 mm×8 mm. The γ-phase was confirmed by single crystal X-ray diffraction, powder XRD and the FTIR analysis. Optical absorption spectrum reveals that the grown crystal has good optical transparency in the entire visible region with an energy band gap of 5.09 eV, which is an essential requirement for a nonlinear optical crystal. Thermal stability of the grown γ-glycine crystal was determined using the thermo gravimetric and differential thermal analyses. The NLO activity of γ-glycine was confirmed by the Kurtz powder technique using Nd:YAG laser and the grown crystal exhibits high relative conversion efficiency when compared to potassium dihydrogen phosphate (KDP).     

Growth and characterization of semiorganic crystal potassium hydrogen oxalate

Single crystals of potassium hydrogen oxalate (KHO), a semiorganic nonlinear optical material, were grown from aqueous solution by slow evaporation solution growth technique at room temperature. The cell parameters of KHO were determined using single crystal X-ray diffraction and the crystal system was identified as monoclinic. The suitability of this material for nonlinear optical application was studied by UV–Vis spectral study and the second harmonic generation efficiency measurement by Kurtz–Perry powder method. The nature of coordination and the functional groups present were investigated by the Fourier transform infrared spectrum. The thermal stability of the crystal was analyzed by thermogravimetric and differential thermal analysis. Vickers microhardness test was carried out on the growth crystal to assess its mechanical stability.     

Synthesis,growth and characterization of nonlinear optical urea–ammonium chloride crystals

Semi-organic nonlinear optical urea–ammonium chloride (UAC) crystals have been grown from aqueous solution by slow evaporation technique. The lattice parameters of the grown crystals were determined by X-ray diffraction studies. The presence of functional groups was determined using Fourier transform infrared (FTIR) analysis. The thermal analysis studies indicate that the material possess optimum thermal stability. Optical absorption studies show low absorption in the entire visible region and UV cut – off is found to be at 240 nm. The presence of second harmonic generation (SHG) for the grown crystal was confirmed by Kurtz powder technique.     

Synthesis, growth, thermal, optical and mechanical properties of 2-Aminopyridinium 4-methylbenzoate Dihydrate

Organic NLO material of 2-Aminopyridinium 4-methylbenzoate Dihydrate (2A4M) was synthesized using 2-Aminopyridinium and 4-methylbenzoic acid as starting materials. Single crystals of 2A4M were grown by the slow evaporation solution growth technique at room temperature using water as a solvent. The grown crystal was characterized by single crystal XRD to confirm the crystal system and lattice parameters. From the optical studies the optical band gap and the refractive index of the material are found to be 2.9 eV and 1.40 at 1200 nm. Functional groups of the crystallised material were confirmed by FTIR vibrational spectrum. Thermal behaviour of the title compound was studied using thermogravimetric (TG) and differential thermal analyses (DTA). The initial weight loss is found up to 125°C, which corresponds to 13.2% i.e. presence of 2 mole of water in the lattice. The grown crystal was subjected to Vickers hardness test and the brittleness index, fracture toughness, yield strength were estimated. The etching studies reveal the growth pattern and dislocations present in the grown crystal. The second harmonic generation (SHG) behaviour of 2A4M was tested by Kurtz-Perry powder technique. The relative SHG efficiency of 2A4M is found to be 3.03 times that of the reference material KDP.     

Growth, characterization, vibrational spectroscopic and thermal studies of a new metallorganic non-linear optical crystal-Bisthiourea cadmium bromide

Single crystals of bisthiourea cadmium bromide (BTCB), a new metallorganic material crystallizing in orthorhombic system were grown from slow evaporation solution growth. The grown crystals were characterized by X-ray diffraction, FTIR and FT-Raman spectral studies. The crystals were also subjected to TGA/DTA analysis and second harmonic generation test. The transmission characteristics of the crystal was also studied.     

Structural, thermal and optical characterization of an organic NLO material--benzaldehyde thiosemicarbazone monohydrate single crystals

Single crystals of the organic NLO material, benzaldehyde thiosemicarbazone (BTSC) monohydrate, were grown by slow evaporation method. Solubility of BTSC monohydrate was determined in ethanol at different temperatures. The grown crystals were characterized by single crystal X-ray diffraction analysis to determine the cell parameters and by FT-IR technique to study the presence of the functional groups. Thermogravimetric and differential thermal analyses reveal the thermal stability of the crystal. UV-vis-NIR spectrum shows excellent transmission in the region of 200-1100 nm. Theoretical calculations were carried out to determine the linear optical constants such as extinction coefficient and refractive index. Further the optical nonlinearities of BTSC have been investigated by Z-scan technique with He-Ne laser radiation of wavelength 632.8 nm. Mechanical properties of the grown crystal were studied using Vickers microhardness tester. Second harmonic generation efficiency of the powdered BTSC monohydrate was tested using Nd:YAG laser and it is found to be ～5.3 times that of potassium dihydrogen orthophosphate.     

Studies on the growth, spectral, optical, and thermal aspects of a NLO crystal

Nonlinear optical single crystal l-tryptophan hydrogen selenite (LTHS) has been synthesized by slow evaporation solution growth technique from aqueous solution at ambient temperature. The grown nonlinear optical crystals were subjected to single crystal XRD analysis to find the structure parameters. The formation of the product was confirmed from the FTIR and ¹HNMR spectral analysis. The UV–Vis spectral studies showed that the cutoff wavelength for LTHS was less than 400 nm. The thermal behavior of the grown crystals was investigated from thermogravimetry and differential thermal analysis. Its nonlinear optical property has been tested by Kurtz–Perry powder technique using Nd:YAG laser, and the crystal exhibited second harmonic generation property.     

Preparation and characterization of a bis thiourea sodium iodide (BTSI)

A semi-organic nonlinear optical single crystal of bis thiourea sodium iodide (BTSI) has been successfully grown from aqueous solution using the slow evaporation solvent technique (SEST) at room temperature. Obtained crystals using the SEST method were characterized by using different characterization techniques. Structural studies of the grown crystals have been carried out by single-crystal XRD to confirm the crystal system and functional groups by FT-IR spectroscopy. Single-crystal XRD reveals orthorhombic structure of semi-organic BTSI single crystals and its unit cell parameters. Metal complex coordination of the single crystal is studied by FT-IR spectroscopy. The optical absorption study revealed excellent optical transparency of BTSI crystal in the entire visible region with a sharp lower cutoff wavelength 298 nm. The energy band gap of BTSI is found to be 4.16 eV. Thermal stability and thermal decomposition of BTSI single crystals were investigated by TGA–DTA and DSC analysis. The surface appearance of BTSI crystals by scanning electron microscopy reveals the formation of layer growth pattern. The structural perfection and growth features of the grown crystal were analyzed by wet chemical etching studies. The above studies reveal the effect of incorporation of sodium iodide into the lattice of thiourea crystals. The as-grown BTSI single crystals can be used as a potential candidate for NLO material as well as in electronic and optoelectronic devices.     

Studies on crystal growth, vibrational and optical properties of organic nonlinear optical crystal: p-aminoazobenzene

p-Aminoazobenzene (p-AAZB), an organic nonlinear optical (NLO) crystal having good optical quality has been grown by slow evaporation solution technique using ethanol as a solvent. Solubility studies were performed at different temperatures. The structural characterization of the grown crystals was carried out by X-ray diffraction. Group theoretical analysis was carried out to calculate the number of modes of vibration. The lowering of the wave numbers of azo group suggests the existence of strong intermolecular N-H...H hydrogen bonding. This has been analysed based on the vibrational spectral features. Optical absorption studies show the effective transmission in the entire UV-vis region. The second harmonic generation results show the suitability of this material for NLO applications.     

Synthesis, growth, spectral, thermal, mechanical and optical properties of 4-chloro-4′dimethylamino-benzylidene aniline crystal: A third order nonlinear optical material

An organic nonlinear optical material, 4-chloro-4′dimethylamino-benzylidene aniline (CDMABA), was synthesized by the condensation of the p-chloroaniline and p-dimethylaminobenzaldehyde. Solubility of CDMABA was determined in acetone at different temperatures. Single crystals were grown by the solvent evaporation method from acetone solution at room temperature. Grown crystal was subjected to FTIR, FT-Raman and ¹H NMR spectral analyses to confirm the synthesized compound. The range and percentage of optical transmission was ascertained by recording UV–vis–NIR spectrum. Thermal properties were investigated by Thermo Gravimetric, Differential Thermal and Differential Scanning Calorimetric analyses. High Resolution X-ray Diffractometry (HRXRD) was employed to evaluate the perfection of the grown crystal. The third order nonlinear optical parameters (nonlinear refractive index and nonlinear absorption coefficient) were derived by the Z-scan technique.