Spectral, optical, and thermal studies of pure and Zn(II)-doped l-histidine hydrochloride monohydrate (LHHC) crystals

The influence of doping the transition metal Zn(II) on the growth, spectral, optical, and thermal properties of l-histidine hydrochloride monohydrate (LHHC) crystals grown by slow solvent evaporation method has been investigated. Structural characterizations of the grown crystals were carried out by single crystal X-ray diffraction analysis and it shows slight structural changes as a result of doping. The FT-IR spectral study reveals the presence of various functional groups and confirms the slight distortion of the structure of the crystals due to doping. The energy dispersive X-ray analysis reveals the incorporation of Zn(II) in the crystalline matrix of LHHC crystal. The UV?CVis spectral study was carried out to analyze the optical transmittance of the grown crystals and found that the transmittance is very high in the visible and UV regions for both pure and doped crystals. The second harmonic generation (SHG) for the grown crystals was confirmed by Nd:YAG laser. The scanning electron microscopy reveals the presence of defect centers and crystal voids. The thermal stability and purity of the grown crystals were analyzed by thermogravimetry, differential thermal analysis, and differential scanning calorimetry techniques.     

Effect of NaCl and KCl doping on the growth of sulphamic acid crystals

The nonlinear optical single crystals of doped sulphamic acid (SA) were grown from aqueous solution by doping with NaCl and KCl using slow evaporation method. Powder X-ray diffraction studies confirm that the grown crystals belong to orthorhombic system. The density and melting point measurements of the grown crystals were determined by floatation technique and capillary tube method, respectively. The range of optical transmittance was ascertained by recording the UV–Vis–NIR spectrum. Atomic absorption study reveals the presence of dopants in the doped crystals. The thermal analyses indicated that the doped SA crystals are more stable than pure crystals. The Vicker's microhardness studies revealed that the dopants increased the hardness of the crystals. SHG efficiency studies of the crystals are found to be increased in the presence of NaCl and KCl dopants.     

Growth and thermal kinetics of pure and cadmium doped barium phosphate single crystal

Non-isothermal kinetic parameter of pure and cadmium-doped barium phosphate single crystal grown by room temperature solution technique have been investigated. Single crystal X-ray diffraction establishes grown crystal to be orthorhombic in nature. Scanning electron microscopy supplemented with energy dispersive X-ray analysis was used to study the surface features and to find the exact stoichiometric composition of the grown crystal. Fourier transform infrared spectroscopy studies confirm the presence of various functional groups. The effect of cadmium doping on pure barium phosphate single crystal was studied using thermogravimetry analysis. Thermogravimetry studies shows that the pure crystal was stable up to a temperature of 330 °C whereas doped crystal was stable up to a temperature of 240 °C, i.e., pure crystals were more stable than doped ones. Various solid-state reaction kinetics, i.e., activation energy (E _a), frequency factor (Z), and entropy (ΔS*) was calculated out to find the mechanism of thermal decomposition at different stages for pure and cadmium doped barium phosphate.     

Aluminium-doped LiFePO4 single crystals. Part I. Growth, characterization and total conductivity

Single crystals of Al-doped LiFePO4 (1% Al) were grown by an optical floating zone technique. After cleaving from the as-grown ingot they exhibited a blackish-green color. The grown crystals have been characterized by the Laue X-ray technique, single-crystal and powder X-ray diffraction. Phase composition has been determined by chemical analysis to be Li0.985+/-0.009Fe0.984+/-0.12Al0.0126PO3.993+/-0.06. Secondary ion beam spectroscopy (SIMS) indicates a homogeneous distribution of doped Al in the single crystal block. The total conductivities are shown to be electronic conductivities and have been measured along different directions with the help of the cell Ti/LiFe(Al)PO4/Ti. The samples exhibit effectively two-dimensional electronic conductivities along b- and c-directions similar as in pure LiFePO4. This decrease of conductivity on Al-doping compared with undoped crystals is in agreement with our previous conclusion of p-type conductivity of LiFePO4. Unlike nominally pure material not only the association of holes with lithium vacancies plays an important role but also purely ionic association.     

Growth,geometrical analysis,FMO, MEP UV–vis,nonlinear optical and antibacterial properties of pure and 2-furoic acid doped Guanidinium carbonate single crystal

In the presence of distilled water, the adaption of the slow evaporation solution growth approach resulted in the successful development of single crystals of Pure and doped GC (FAGC). The cell characteristics of the produced FAGC crystals were investigated using single-crystal X-ray diffraction analysis. The theoretical analysis was carried out using the DFT method, and the HOMO-LUMO energy band difference was estimated. The Molecular optimized geometry, MEP and HOMO-LUMO energy distance were computed using the B3LYP level of theory using a 6-31G (d,p) basis set. The FT-IR spectrum probes the modes of vibration of various functional groups in pure and doped GC (FAGC) crystals. According to UV–visible NIR transmittance experiments, the formed crystal exhibits a high transmittance in the whole visible range. The relative SHG efficiency of pure and doped crystals (FAGC) was carried out by the Kurtz perry technique. The Antibacterial activity demonstrates that both the pure and the dopant have antibacterial action against dangerous microorganisms.     

Crystal growth,spectroscopic, second and third order nonlinear optical spectroscopic studies of L-phenylalanine doped ammonium dihydrogen phosphate single crystals

The frequency doubling and tripling can be reached for Nd:YAG laser beam using the single crystal of ammonium dihydrogen phosphate (ADP). The growth and characterization of pure and L-phenylalanine doped ADP crystals are considered in the present contribution. The transparent good quality single crystals are grown using low temperature solution growth technique. The functional group alteration is studied using FT-IR spectroscopy. The larger improvement is observed in linear and nonlinear optical properties of ADP crystals on doping by L-phenylalanine. The reduction in charge carrier density is observed in photoconductivity spectra of all the grown crystals.     

Thermal and optical properties of ZTS single crystals in the presence of 1,10-phenanthroline (Phen)

The influence of heteroaromatic N-base (1,10-phenanthroline) (Phen), a new additive as complexing agent on tris(thiourea)zinc(II)sulphate (ZTS) crystals from aqueous solutions at 30 °C is investigated. Crystals were grown using low concentration of the dopant (0.005 M L^?1) in the aqueous growth medium and the growth promoting effect (GPE) is much greater because of an increase in the metastable zone width. High dopant concentration decreases GPE. The crystalline perfection of the grown crystals is quite good both in doped and undoped crystals as evaluated by high-resolution X-ray diffractometry (HRXRD). The diffraction curve of a typical Phen doped as-grown ZTS crystal was observed to contain a single peak indicating that the crystal does not contain any epitaxial layer on the surface or internal structural grain boundaries. Not much variation is observed in FT-IR and XRD of pure and doped ZTS. Phen depresses the NLO efficiency of ZTS. It could be ascribed due to the disturbance of charge transfer in the presence of the dopant. The grown crystals were also characterized by UV–Vis, SEM and TG–DTA techniques.     

Influence of Vo(II) doping on the thermal and optical properties of magnesium rubidium sulfate hexahydrate crystals

We have prepared pure and divalent vanadyl ion-doped magnesium rubidium sulfate hexahydrate crystals by using slow evaporation solution growth technique. It is interesting to observe that Vo(II) doping influences the physical properties of MRSH. Presence of Vo(II) ions in the doped specimen was confirmed by energy dispersive spectroscopy and electron paramagnetic resonance spectroscopy. FTIR studies reveal that the doping of vanadium ion has not altered the basic structure of MRSH. Scanning electron microscope studies of doped sample reveals that structure defect centers are formed in the crystals. Gradual decomposition patterns were observed for pure and doped specimens in thermogravimetry and differential thermogravimetry. The grown crystals were also characterized by powder X-ray diffraction. The second harmonic generation efficiency tested using Kurtz powder technique is not influenced by the added dopant.     

The effect of nitric acid (HNO3) on growth,spectral, thermal and dielectric properties of triglycine sulphate (TGS) crystal

The effect of nitric acid (HNO₃) addition on the growth of triglycine sulphate (TGS) crystal has been studied from the aqueous solution for various concentrations of nitric acid. Significant changes in the crystal size and morphology have been observed in all the grown samples. Single crystal and powder X-ray diffraction analyses confirm the structure and cell parameter values of pure and HNO₃ doped TGS crystals. FT-Raman and FTIR spectra confirm the characteristics absorption bands of pure and HNO₃ doped TGS crystals. The composition of TGS crystals have been confirmed by CHNS analysis. Physical properties such as thermal, dielectric and mechanical studies have been performed for the pure and HNO₃ doped TGS crystals. The dielectric constants of the crystals have been studied as a function of frequency. The results suggest that the HNO₃ is doped into TGS crystal and that the doping increases its dielectric constant.     

Characterization of 4-chloro-3-nitrobenzophenone crystal grown by Bridgman technique

The large size 12 mm diameter 4-chloro-3-nitrobenzophenone (4C3N) single crystal has been grown by using vertical Bridgman technique. The grown crystal was confirmed by Powder X-ray diffraction analysis. The crystalline perfection of the grown crystal was examined by high-resolution X-ray diffraction study. The cutoff wavelength of the grown crystal was analyzed by optical studies. The thermal property of the grown crystal was studied by thermogravimetric and differential thermal analyses. The fluorescence spectra of grown 4C3N single crystals exhibit emission peak at 575 nm. The microhardness measurements were used to analyze the mechanical property of the grown crystal. The laser-induced surface damage threshold for the grown crystal was measured using Nd:YAG laser.     

Growth, structural, vibrational, optical, laser and dielectric aspects of L-alanine alaninium nitrate single crystal

Bulk single crystals of l-alanine alaninium nitrate [abbreviated as LAAN], an intriguing material for frequency conversion has been grown from its aqueous solution by both slow solvent evaporation and by slow cooling techniques. The optimized pH value to grow good quality LAAN single crystal was found to be 2.5. The grown crystals were subjected to single crystal X-ray diffraction studies to determine the unit cell dimensions and morphology. Vibrational frequencies of the grown crystals by Fourier transform infrared spectroscopic technique were investigated. Also, the presence of hydrogen and carbon atoms in the grown sample was confirmed using proton and carbon NMR analyses. The dielectric constant and dielectric loss measurements of the as grown crystal at different temperatures and frequencies of the applied field are measured and reported. LAAN has good optical transmission in the entire visible region with cutoff wavelength within the UV region confirms its suitability for device fabrications. The existence of second harmonic generation signals was observed using Nd:YAG laser with fundamental wavelength of 1064 nm. Its Laser Damage Threshold (LDT) was measured and also tested by using a Q-switched Nd:YAG laser and the value of LDT of LAAN is 17.76GW/cm2 respectively, is found to be better than certain organic and semiorganic materials.     

Growth, structural, spectral, mechanical, thermal and dielectric characterization of phosphoric acid admixtured L-alanine (PLA) single crystals

Phosphoric acid admixtured L-alanine (PLA) single crystals were grown successfully by solution method with slow evaporation technique at room temperature. Crystals of size 18 mm×12 mm×8 mm have been obtained in 28 days. The grown crystals were colorless and transparent. The solubility of the grown samples has been found out at various temperatures. The lattice parameters of the grown crystals were determined by X-ray diffraction technique. The reflection planes of the sample were confirmed by the powder X-ray diffraction study and diffraction peaks were indexed. Fourier transform infrared (FTIR) studies were used to confirm the presence of various functional groups in the crystals. UV-visible transmittance spectrum was recorded to study the optical transparency of grown crystal. The nonlinear optical (NLO) property of the grown crystal was confirmed by Kurtz-Perry powder technique and a study of its second harmonic generation efficiency in comparison with potassium dihydrogen phosphate (KDP) has been made. The mechanical strength of the crystal was estimated by Vickers hardness test. The grown crystals were subjected to thermo gravimetric and differential thermal analysis (TG/DTA). The dielectric behavior of the sample was also studied.     

Crystal growth, thermal and optical studies on a semiorganic nonlinear optical material for blue-green laser generation

The semiorganic nonlinear optical material l-histidine bromide (l-HB) has been synthesized in aqueous solution and characterized by FT-IR, FT-Raman and FT-NMR spectroscopic techniques. The single crystals with dimensions 9mm x 4mm x 3mm were grown by slow evaporation techniques. The grown crystals were subjected to single crystal X-ray diffraction to determine the unit cell dimensions. The thermal stability of the grown crystal was analyzed by thermogravimetric (TG), differential thermal (DT) and differential scanning calorimetric (DSC) analyses. The UV-vis transmittance spectrum shows that it has a good optical transmittance in the entire visible region with the lower cutoff wavelength at 220 nm. The SHG conversion efficiency and laser damage threshold were measured using a Nd:YAG laser (1064 nm). The optical birefringence was measured in the visible region as a function of temperature in the range 30-150 degrees C by interference technique.     

Effect of doping an organic molecule ligand on TGS single crystals

Good quality single crystals of thiourea-doped triglycinesulphate (TuTGS) a new semiorganic nonlinear optical (NLO) crystal has been successfully grown from aqueous solution by slow evaporation method. The solubilities under various solvents in different proportions have been studied. The structural characterization of the grown crystals was carried out by X-ray diffraction. The grown crystals were subjected to FTIR and Raman analyses for vibrational assignments. The optical absorption coefficient alpha was analysed and interpreted to be allowed in the direct transition. The values of allowed direct energy gap (Eg) for undoped and doped crystals were calculated. It was found that Eg values were decreased with organic molecule doping. The powder technique of Kurtz and Perry confirm the NLO property of the grown crystal.     

Influence of Zn2+ ion on the organometallic l-alanine cadmium chloride single crystals

The single crystals of pure and zinc chloride-doped l-alanine cadmium chloride (LACC), an organometallic nonlinear optical material, are grown by a slow evaporation technique. The grown crystals were subjected to X-ray diffraction analysis, scanning electron microscopic study, and energy-dispersive analysis by X-ray and thermal studies. The second harmonic generation was confirmed by the Kurtz and Perry powder technique. The dielectric measurements were carried out for different frequencies at different temperatures. The second harmonic efficiency and dielectric constant increases significantly due to introduction of smaller ionic radii Zn²⁺ ion into the lattice of pure LACC crystal; so that the zinc chloride-doped LACC crystals are found to be potential material for nonlinear frequency conversion.     

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.     

Growth, optical, mechanical and thermal studies of diglycine cadmium chloride single crystal

Transparent single crystals of diglycine cadmium chloride were grown by slow evaporation solution technique. To confirm the crystal structure, the grown crystals were subjected to single crystal as well as powder X-ray diffraction measurements and the structure was found to be monoclinic. The elemental analysis was carried out by energy dispersive X-ray spectroscopy. The crystalline perfection of the grown crystal was assessed by high-resolution X-ray diffractometry and found that the crystal quality is fairly good. The optical study reveals that the grown crystal is highly transparent in the region 250?C900?nm. Thermal studies reveal that the grown crystal is stable up to 245?°C. The michrohardness analysis revealed that the grown crystal belongs to soft material category. The high dielectric constant (>30) and low loss (<0.01) value also confirms that the grown crystal is a good candidate for device fabrications.     

Growth and characterization of semi-organic nonlinear optical crystal

A new nonlinear optical crystal urea thiourea cadmium sulfate (UTCS) has been grown by slow evaporation technique in equimolar ratio. The grown crystals were characterized by single crystal X-ray diffraction analysis which reveals that sample crystallizes in triclinic system with non-centrosymmetric space group P1. The powder XRD pattern revealed the formation of UTCS compound. High-resolution-X-ray diffraction analysis was carried out to study the crystalline perfection of the sample. Functional groups of the grown crystal were identified by FT-IR studies. Thermo gravimetric and differential thermal analyses were employed to understand the thermal and physio-chemical stability of the synthesized compound. UV–Vis–NIR spectrum revealed the transmission properties of the crystal specimen. The SHG efficiency has been tested by the Kurtz powder technique using Nd: YAG laser and found to be about 0.82 times in comparison with standard KDP crystals.     

Crystal growth, structural, optical, spectral and thermal studies of tris(L-phenylalanine)L-phenylalaninium nitrate: a new organic nonlinear optical material

Tris(L-phenylalanine)L-phenylalaninium nitrate, C(9)H(12)NO(2)(+)·NO(3)(-)·3C(9)H(11)NO(2) (TPLPN), a new organic nonlinear optical material was grown from aqueous solution by slow evaporation solution growth at room temperature. The grown crystals were subjected to powder X-ray diffraction and single crystal X-ray diffraction studies to confirm the crystalline nature and crystal structure. The modes of vibration of different molecular groups present in TPLPN have been identified by FTIR spectral analysis. The presence of hydrogen and carbon in the grown crystal were confirmed by using proton and carbon nuclear magnetic resonance (NMR) spectral analyses. The optical transmission spectral study establishes good transmitting ability of the crystal in the entire visible region. The thermogravimetric (TG) and differential thermal analyses (DTA) were carried out to understand the thermal stability of the sample. The nonlinear optical property of the compound observed using Kurtz powder second harmonic generation test assets the suitability of the grown material for the frequency conversion of laser radiation of Nd:YAG.     

Studies on the growth, optical, electrical and spectral properties of potassium pentaborate (KB5) single crystals

The bulk single crystals of nonlinear optical material potassium pentaborate (KB5) have been grown by slow evaporation solution growth technique using water as solvent. The grown crystal was confirmed by single crystal X-ray diffraction studies. The structural perfection of the grown crystals has been analyzed by high resolution X-ray diffraction (HRXRD) studies by recording rocking curve. The photoluminescence (PL), UV-vis spectral studies were performed and the optical bandgap of the material was calculated. FTIR and FT-Raman measurements enumerate the functional groups present in the compound. The factor group analysis on KB5 reveals that there are 117 vibrational optical modes. The dielectric behavior of KB5 was investigated with different frequencies and temperatures.