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.     

Growth and characterization of l-prolinium picrate single crystal: A promising NLO crystal

l-Prolinium picrate was synthesized and its solubility in the mixed solvent of acetone and water was estimated. Employing temperature reduction method crystals of size 22×4×3 mm³ were grown. The cell dimensions were obtained by single-crystal X-ray diffraction study. FT-IR, UV–vis–NIR and fluorescence spectral analyses were carried out for the grown crystals. The optical band gap estimated for this crystal is about 2.4 eV. Thermogravimetric study was carried out to determine the thermal properties of the grown crystal. Kurtz powder second harmonic generation (SHG) efficiency measurement revealed that the SHG efficiency is about 52 times that of potassium dihydrogen orthophosphate. Mechanical strength was tested by Vicker's microhardness test.     

Growth and physical properties of a new chiral open-framework crystal for NLO applications: Cesium hydrogen l-malate monohydrate

Cesium hydrogen l-malate monohydrate, CsH(C₄H₄O₅)·H₂O, is a new chiral open-framework semi-organic crystalline material with a second-harmonic generation efficiency one order of magnitude greater than KDP. Single crystals of this new material have been grown by the conventional slow cooling technique from aqueous solution. Grown crystals display both platy and prismatic morphologies depending on the imposed supersaturation. Hardness values measured using Vickers hardness indenter show considerable anisotropy. The resistivity behavior at room temperature and above, places the crystal between an ionic conductor and a dielectric. The single-crystal SHG efficiency estimated through Maker fringes experiment gives d_eff which is 4.24 times that of KDP. Single and multiple shot experiments performed on the grown crystals for the fundamental and second harmonic of pulsed Nd:YAG laser (1064 and 532 nm) show that it exhibits a high laser damage threshold which is a favorable property for nonlinear optical applications.     

Synthesis,growth and characterization of l‐alaninium oxalate ‐ a novel organic NLO crystal

Nonlinear optical material of L‐alaninium oxalate (LAO) has been synthesized and single crystals are grown by slow evaporation technique. The solubility data of LAO is determined in water. Single crystal X‐ray diffraction study showed that LAO belongs to orthorhombic system with a non‐centrosymmetric space‐group P2₁2₁2₁. The functional groups have been identified from FT‐IR spectrum. The UV‐Vis‐NIR spectrum of LAO shows less optical absorption in the entire visible region. The second harmonic generation (SHG) in the material was estimated using Nd:YAG laser. The mechanical properties of the grown crystals are studied using Vickers microhardness tester. The AC and DC conductivity, and dielectric studies are also carried out and reported for the first time. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of semiorganic NLO crystals of LAHClBr

Single crystals of non‐linear optical (NLO) LAHClBr were grown by slow evaporation technique from its aqueous solution. Good optical quality crystals having dimensions up to 12 × 9 × 7 mm³ were obtained. The lattice parameters and morphology for the grown crystals were determined using single crystal XRD. The crystals were characterized by FT‐Raman, optical absorption, thermal (DTA and TGA) and dielectric studies. LAHClBr was found to be thermally stable up to 124.3°C. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of glycine doped bis thiourea cadmium chloride single crystal

Single crystal of 2 mol% glycine doped Bis Thiourea Cadmium Chloride, a semi organic nonlinear optical material has been grown by slow evaporation technique. Good quality single crystal with dimension 14 × 12 × 5 mm³ was harvested after 35 days. The influence of amino acid glycine was studied for 1, 2 and 3 mol% glycine doped Bis Thiourea Cadmium Chloride by Kurtz and Perry powder second harmonic generation test and compared with pure Bis Thiourea Cadmium Chloride which confirms the enhancement of second harmonic generation property of glycine doped Bis Thiourea Cadmium Chloride. The large enhancement was found for 2 mol% glycine doping. The grown crystal was characterized by various characterizations viz. single crystal X‐ray diffraction, energy dispersive X‐ray (EDAX), Fourier Transform Infrared Spectroscopy (FTIR) analysis, UV‐visible absorption, thermo gravimetric analysis (TGA). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of Imidazolium adipate (IA) single crystal

Bulk single crystals of Imidazolium adipate (IA) were grown by solution growth method at 35 °C temperature. The solubility measurement of the material was carried out. FT-IR spectral analysis confirms the functional groups of the IA compound. Linear and nonlinear optical properties of the crystal were analyzed by UV-Vis-NIR transmittance and SHG studies. The high transparency with wide band gap is useful for optoelectronic applications are indicated. The SHG efficiency was higher than KDP. Vickers hardness study confirmed that the crystal was soft nature. Thermal stability of the material is up to 80 °C and the electrical study was carried out.     

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.     

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 doped hippuric acid crystals for NLO devices

Modified hippuric acid (HA) single crystals have been grown from aqueous solution of acetone by doping with NaCl and KCl using slow evaporation technique at constant temperature, with the vision to improve the physicochemical properties of the sample. The characterisation of grown crystals was made by X‐ray powder diffraction, density and melting point measurements. TGA/DTA studies indicate that doped crystals are more stable than pure crystals. The optical transmission study and Kurtz powder SHG measurement shows the suitability of doped crystals for NLO applications. Dopant concentration is identified with ICP atomic emission spectrometer system. The Vicker's hardness studies at room temperature, carried out on (111) crystallographic plane shows increased hardness of the doped crystals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

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)     

Growth and characterization of Ytterbium doped KGd(WO4)2 single crystal

Single crystals of Ytterbium doped KGd(WO₄)₂ were grown by Top Seeded Solution Growth technique using K₂WO₄ as flux system. The growth parameters were optimised to get optically transparent crystals. Variation in the lattice parameters were observed in comparison to the pure KGd(WO₄)₂ crystals. The absorption spectra recorded for the Yb:KGW confirms the material suitability for diode pumped solid state lasers. The vibrational studies carried out using spontaneous Raman spectra indicate the strong anionic vibration of the material. PL spectra show the lasing channel of the laser active ions present. Stimulated Raman scattering analysis confirms the material as an efficient Raman laser material. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of nonlinear optical zinc hydrogen phosphate single crystal grown in silica gel

Good optical quality single crystals of zinc hydrogen phosphate (ZnHPO₄) having dimensions up to 8×2×2 mm³ have been grown with the aid of sodium meta silicate gel. Single crystal XRD studies confirm that the crystal belongs to the orthorhombic system with space group P2₁2₁2₁. The functional groups present in the crystals were confirmed using FTIR technique. Optical absorbance shows very low absorption in the entire visible region. Differential thermal and thermo gravimetric analysis confirmed that the crystal is stable up to 193°C. Photoconductivity study reveals positive photoconductivity in the presence of photo active centers formed by trap energy levels. The NLO activity of the crystal was confirmed by Kurtz powder technique. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

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 a promising nonlinear optical organic crystal

The growth of single crystals of acetoacetanilide using slow evaporation technique is reported. Good-quality crystals up to a size of 20×10×1 mm³ are obtained. The grown crystals are characterized by employing UV-VIS spectrum, IR spectrum, and hardness measurements. Acetoacetanilide shows very good second-harmonic generation (SHG) efficiency.     

Synthesis,characterization and crystal structure of a novel 2D Ni(II) complex with malate

An exploration of the nickel‐ malate‐bpa system under hydrothermal conditions, has led to the isolation of a novel framework {[Ni(Hmal)(bpa)]·2.5H₂O}_n ( 1 ) (Hmal = malate dianion, bpa = 1,2‐bi(4‐pyridyl)ethane). Single‐crystal X‐ray analyses reveal that it crystallizes in the orthorhombic space group Fdd2. a = 21.9944(13) Å, b =33.3369(19) Å, c = 10.3969(5) Å, β = 90°. The Ni^II ions are linked into an extended helical chain via Hmal molecules. Further these chains are united together through the bridging bpa to form a 2D grid layer, which exhibits a typical (6,3) topological network. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of pure and metal doped bis(thiourea) zinc chloride single crystals

Metal (Cd²⁺ and Cu²⁺) substituted single crystals of Bis(thiourea) zinc chloride (BTZC) are grown by slow solvent evaporation technique, with the vision to improve the physicochemical properties of the sample. Single crystal XRD studies of both pure and doped samples are carried out and the results are compared. Optical absorption and FTIR studies are performed to identify the UV cut‐off range and the presence of various functional groups in the grown crystals. The thermogravimetric (TG) analysis of metal doped BTZC indicates a marginal increase in the thermal stability of the crystals. The dielectric response of the samples have been studied in the frequency range 100 Hz to 5 MHz at room temperature and the results are discussed. Photoconductivity studies carried out on pure and metal doped BTZC crystals revealed the negative photoconducting nature. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of non‐linear optical crystal ZnCd(SCN)4

Single crystals of ZCTC with dimension up to 5x2x3mm³ were grown from aqueous solution by slow solvent evaporation method and the grown crystals were confirmed by single XRD and CHN analysis. The SHG efficiency of ZCTC was evaluated using Kurtz Perry technique. Its efficiency was found to be nearly 12 times that of urea when studied with the fundamental wavelength of 1064 nm. The mechanical properties of the grown crystal have been investigated by Vickers microhardness testing. The thermal parameters such as the thermal diffusivity (α), thermal effusivity (e), thermal conductivity (k) and heat capacity (c_p) of ZCTC were measured by an improved photopyroelectric (PPE) technique and the results were discussed. The TG/DTG studies reveal that the decomposition of the sample begins around 350°C. The photoconducting nature of ZCTC has also been investigated and reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of a new semi organic NLO material: L‐tyrosine hydrochloride

Single crystals of L‐Tyrosine hydrochloride were grown by using the submerged seed solution method. The grown crystals were characterized by using single crystal X‐ray diffraction. Functional groups and the modes of vibrations were identified by FTIR spectroscopy. The TGA/DTA studies showed that the crystal is stable up to 232°C. Microhardness study revealed that the crystal is a hard material. It is transparent in the entire visible region. The SHG efficiency was determined by the Kurtz and Perry method. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,characterization, crystal structure and NLO properties of a new mixed crystal potassium sodium ammonium dihydrogenphosphate K0.23Na0.23(NH4)0.54H2PO4

Potassium sodium ammonium dihydrogenphosphate K_0.23Na_0.23(NH₄)_0.54H₂PO₄ (KSADP), a new mixed crystal has been grown in aqueous medium by the slow evaporation of equimolar mixture of ammonium dihydrogenphosphate (ADP), potassium dihydrogenphosphate (KDP) and sodium dihydrogenphosphate (SDP). Crystal composition as determined by single crystal X-ray diffraction analysis reveals that it belongs to the tetragonal system with noncentrosymmetric space group I-42d and it is structurally similar to ADP with cell parameter values, a=7.4794(4) Å; b=7.4794(4) Å; c=7.2974(11) Å; υ=408.23(7) Å³; z=4. The presence of sodium and potassium in ADP matrix was confirmed by inductively coupled plasma emission spectrometry and energy dispersive X-ray spectroscopy. The partial cationic substitution results in defect centers influencing the physical properties. Slight shifts in vibrational patterns could be attributed to strains in the lattice. Refinement of structure by single crystal XRD analysis reveals that potassium, sodium and ammonium coexist in the mixed crystal. The surface morphology of the as-grown specimen, which is changed as a result of cationic incorporation, was studied by scanning electron microscopy. The relative second harmonic generation (SHG) efficiency measurements revealed that the mixed crystal has a superior NLO activity than ADP.