Γ-glycine Single Crystals Research Articles

Comment on the paper “synthesis, nucleation kinetics, spectral, structural, mechanical, and thermal studies of semi-organic barium-doped γ-glycine single crystal” by K. Premlatha et al. [J. Mater. Sci.: Mater. Electron. 32 (2021) 28494]

Comment on the paper “synthesis, nucleation kinetics, spectral, structural, mechanical, and thermal studies of semi-organic barium-doped γ-glycine single crystal” by K. Premlatha et al. [J. Mater. Sci.: Mater. Electron. 32 (2021) 28494]

Local piezo- and ferroelectric properties of γ-glycine single crystal observed via piezoresponse force microscopy

In this work, we demonstrate an approach of local mechanical polishing processing to modify the type of intrinsic piezoelectric activity of γ-glycine polymorph grown in a form of a single crystal. By using the piezoresponse force microscopy, the increase in intensity for both out-of-plane (3 times) and in-plane (5 times) piezoelectric tensor components is demonstrated. Application of local switching spectroscopy reveals the piezoelectric behavior of non-polished and the ferroelectric behavior of polished areas being related to the local mechanical polishing-assistant rearrangement of NH 3+ tails of zwitterions in polymorph molecular chain of γ-glycine. These rearrangements were demonstrated to facilitate the switching behavior of the local dipole moment at the applied electric field surpassing the internal coercive field of about Ec ∼ 3 G V /m .

Synthesis, nucleation kinetics, spectral, structural, mechanical, and thermal studies of semi-organic barium-doped γ-glycine single crystal

Synthesis, nucleation kinetics, spectral, structural, mechanical, and thermal studies of semi-organic barium-doped γ-glycine single crystal

Contemporary studies on growth and characterization of Magnesium doped γ-glycine – A potential optoelectronic NLO material

The optical quality magnesium doped γ-glycine single crystal has been grown by slow evaporation method. The grown crystal was identified as P31 space group based on single crystal X-ray diffraction analysis. The obtained unit cell dimensions a = 7.05 Å, b =7.05 Å, c =5.51Å and α = β = 90o and γ =120o showed that the crystal is hexagonal. The transmittance of the crystal is measured and the UV cut off wavelength was found to be 340 nm and band gap of the crystal is found to be 3.5hν. The various functional groups associated with the grown single crystal have been characterized by FT-IR studies, measured in the range from 450-4000 cm−1. The hardness number and Mayer index value calculated using Microhardness studies established the good mechanical strength of the grown crystal. Simple harmonic generation studies showed that the crystal is having NLO nature. To get the knowledge of crystal surface morphology, SEM studies were carried out. The decomposition temperature of the crystal was identified using TG-DSC studies which indicated that the crystal is thermally stable up to 492.5°C. The laser damage threshold (LDT) studies also supported the suitability of the crystal towards non linear optical applications. Etching studies indicated the minimal dislocations in the crystal growth mechanism. The present study clearly shows that the grown crystal is having potential applications in NLO-optoelectronic devices.

Growth of γ-glycine single crystals using the tailored additive of potassium chloride and L-Proline and analyzing micro structural, optical, mechanical and electrical parameters

Growth of γ-glycine single crystals using L-Proline (1 M) and potassium chloride (0.15, 0.25, 0.35 and 0.45 M%) were successfully grown by solvent evaporation technique. The XRD study confirmed the γ-polymorphism in glycine and achieved only at specific ratio of KCl (0.15 M%) and L-Proline (1 M), but maximum at 0.25 M% KCl. FE-SEM mapping spectrum confirms the elemental distribution and UV–Visible spectrum shows that KCl mediated (0.25 M%) γ-glycine exhibited the high optical property and TG/DTA shows the higher stability. The mechanical strength and dielectric was assessed by micro hardness and EIS analysis. These achieved SHG efficiency as 75% regarding to KDP crystal.

Potential Prebiotic Relevance of Glycine Single Crystals Enclosing Fluid Inclusions: An Experimental and Computer Simulation with Static Magnetic Fields

Glycine crystallizes into three different polymorphs called α, β and γ under standard physicochemical conditions. They have different features depending on their structural variations. The possible interaction of glycine with magnetic minerals in meteorites and comets or in the ancient Earth, paves the way to study the self-assembly and molecular behavior under irradiation and magnetic conditions. The magnetic field might induce the formation of a specific polymorph of glycine. To gain insight on the consequences of gamma irradiation with a gradient of static magnetic fields (0.06 T, 0.3 T, 0.42 T and 0.6 T) on the self-assembly of single macroscopic glycine crystals, we gamma irradiated the powdered amino acid and then assembled single crystals from water solutions. The preliminary results showed a stable formation of fluid inclusions in the single crystals and no straightforward effect on the self-assem- bly process after glycine gamma irradiation and interaction with static magnetic fields. The α glycine polymorph single crystals formed at 55° from the magnetic longitudinal axis and seemed to be enhanced by gamma radiation. The γ-glycine single crystals presented L and D circular dichroism signals, whereas the irradiated samples presented no circular dichroism bands. Com- puter simulations suggest different catalytic properties from α and γ glycine crystals.

Importance of cesium carbonate additives in the nucleation and growth of α- and γ-glycine single crystals

In the present work, successful growth of α- and γ-glycine single crystals using cesium carbonate (Cs2CO3) as an additive has been reported. The powder XRD study confirms that the grown 0.2 M cesium carbonate added glycine crystal has α-glycine crystal morphology and it crystallized in a monoclinic crystal structure with a space group of P21/n. In a similar manner, the PXRD patterns recorded for 0.4, 0.6, 0.8 and 1 M concentrations of cesium carbonate added glycine crystals and the obtained PXRD patterns authenticated that the harvested grown crystals belong to hexagonal crystal system with space group P31. The variation of dielectric constant and dielectric loss for the γ-glycine single crystal was carried out as a function of frequency and the results were discussed in detail. The transmittance spectrum shows that the grown α- and γ-glycine crystals had an extensive optical transparency window in the entire spectrum especially in visible region. The band gap varies from 4.59 to 6.01eV. The positive photoconducting nature of the grown γ-glycine single crystal in the presence of cesium carbonate was studied by the photoconductivity study. The second harmonic generation (SHG) for the prepared γ-glycine single crystals was studied by using Kurtz and Perry powder technique with Nd-YAG laser. The result shows that the prepared γ-glycine single crystals exhibit enhanced second harmonic conversion efficiency and it proves that these crystals are an alternate to KDP crystal in optoelectronic devices and NLO applications.

Growth and characterization of γ-glycine single crystals for photonics and optoelectronic device applications

In this present work, MnSO4-added glycine single crystals were grown by slow solvent evaporation method. Powder XRD study confirms that the crystals grown in γ-phase and it crystallizes in hexagonal structure with a space group of P31. Differential Scanning Calorimetry study revealed that the thermal characteristics of the grown polymorph. The dielectric constant and dielectric loss of grown crystal was carried out as a function of frequency and the results were discussed. The positive photoconducting nature of the grown crystals was studied by photoconductivity study. Non-Linear Optical (NLO) productivity of grown γ-glycine crystal was measured by using Nd: YAG laser. It was found to be 1.67 times higher than that of a reference (KDP).

Optical, photoconductivity and dielectric studies of zinc sulphate added glycine crystal for photonics applications

In present studies, we have successfully grown γ-glycine single crystal in the presence of ZnSO4 as an additive by using slow solvent evaporation method. Powder X-ray Diffraction study confirms crystal grown in γ-phase and it crystallizes into a hexagonal structure with a space group of P31. UV–vis transmittance spectra was recorded for the sample to analyse the optical transparency in visible and near infrared region (NIR). In Kurtz-Perry powder test, SHG efficiency of the grown ZnSO4 added glycine crystal is found to be 3.18 times higher than reference KDP crystal. The dielectric constant and dielectric loss of ZnSO4 added glycine crystal was carried out as a function of temperature by varying the frequency and the obtained results were discussed. The photoconductivity study confirms the positive photoconducting nature of grown ZnSO4 added glycine crystal.

Growth and characterization of nonlinear optical crystal Gamma glycine by the additive of lithium bromide

Single crystal of γ-glycine, a polymorphic form of glycine, was grown by slow solvent evaporation technique by the additive of lithium bromide. It was grown from the aqueous solution of glycine and lithium bromide in 2:1 M ratio respectively at room temperature. Good quality of γ-glycine single crystals was harvested up to the dimension of 25 × 22 × 20 mm3. In order to reveal its properties, the grown single crystals were subjected to various characterizations. Powder X-ray diffraction of the grown crystal was recorded and indexed. The unit cell parameters of the crystals were estimated by single crystal x-ray diffraction and they were compared with the literature values. The identification of the functional groups and hence the compound present in the crystalline sample by FTIR analysis confirms the polymorphic form of glycine. Optical transmittance studies were carried out by UV–Vis-NIR transmission spectrum in the range of 200–1100 nm wavelength. The powdered sample of the crystal was subjected to Kurtz Perry powder technique to find the coefficient of Second harmonic generation. The second harmonic generation (SHG) conversion efficiency of γ-glycine crystal is more than twice when compared with KDP crystal. The grown γ-glycine crystal was further characterized by Thermo gravimetric analysis (TGA) and Differential thermal analysis, to find its thermal stability and decomposition temperature. Dielectric constant and Dielectric loss were determined at different frequencies with respect to various temperatures. The mechanical properties such as microhardness and yield strength were evaluated by Vicker’s microhardness tester.

Synthesis, growth, spectral, electrical, mechanical and thermal characterization of a potential optical material: γ-glycine single crystal

Gamma glycine, an organic material was grown by slow solvent evaporation method. Conventional polythermal method was employed in the temperature range, 30–50 °C to obtain the solubility and the metastable zonewidth. The crystal and molecular structures were analyzed by X-ray powder diffraction, FT-IR and FT-Raman spectral studies. Optical refractive index was determined by prism coupling technique and was found to be 1.4488. Electrical properties such as ac conductivity and activation energy were studied for different temperatures in the frequency range from 40 Hz to 6 MHz. The dc electrical conductivity was estimated from the Cole-Cole plot and the values were found to be 2.19 × 10−6 Sm−1 at 353K and 1.46 × 10−6 Sm−1 at 373K respectively. Mechanical studies on the grown crystal revealed that the material belongs to soft materials category. Thermal conductivity and specific heat capacities were estimated by Hot Disk Thermal Constants Analyzer.

Influence of rare earth gadolinium nitrate addition on structural, dielectric, linear and nonlinear optical properties of glycine single crystals

In this present work, we have successfully grown γ-glycine single crystals in the presence of gadolinium nitrate as an additive by using slow solvent evaporation method. Powder X-ray Diffraction study confirms γ-polymorph structure and it crystallizes into a hexagonal crystal system with a space group of P31. UV–Visible transmittance spectra was recorded for the grown crystal to analyse the transparency in visible and near infrared region (NIR). In Kurtz-Perry powder test, the SHG efficiency of grown crystal is found to be 3.125 times higher than reference KDP crystal. The dielectric constant and dielectric loss of gadolinium nitrate added glycine was carried out as a function of frequency and the obtained results were discussed. The photoconductivity study confirms the positive photoconducting nature of grown crystal.

Investigations on the growth and characterization of γ-glycine single crystal in the presence of sodium bromide

A nonlinear optical material γ-glycine single crystal was grown for the first time in the presence of sodium bromide by slow cooling method. The solubility of the material was analyzed gravimetrically. Metastable zonewidth was studied by the polythermal method. The form of crystallization was confirmed by powder X-ray diffraction analysis. The crystal of γ-glycine were found to crystallize in hexagonal crystal system. The presence of all the functional groups of the γ-glycine was confirmed by FT-IR and FT-Raman spectral analysis. Thermal properties of the grown crystal were determined by thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA), which indicated the thermal stability (up to 210°C) and the melting point (257°C). The grown crystal was subjected to Vickers microhardness test. The dielectric response of the sample is studied as a function of frequency and temperature. The optical transparency and lower cut-off value of UV transmission (223nm) were ascertained by recording a UV–visible spectrum of γ-glycine crystal. The second-order nonlinear optical property was confirmed by Q-switched Nd:YAG laser.

Influence of sodium formate in γ-glycine single crystals – Synthesis, growth and characterization

Single crystals of γ-glycine in the presence of sodium formate were grown first time by slow evaporation method at room temperature. Crystalline nature of the material was confirmed by single crystal X-ray diffraction analysis. Solubility of the material was determined by gravimetric method. UV–Vis–NIR analysis were carried out to find the optical absorbance of the material. The presence of functional group was confirmed by Fourier Transform-Infrared analysis (FT-IR). Thermal stability and decomposition of the grown crystal were studied by Thermo gravimetric/Differential thermal analysis (TG/DTA). Energy dispersive X-ray analysis (EDAX) revealed the presence of elements in the grown crystal. The nonlinear optical response of the grown crystal was confirmed by Q-switched Nd-YAG laser and second harmonic generation efficiency of the grown crystal was found to be greater than that of KDP.

Synthesis, growth and characterization of γ-glycine – A promising material for optical applications

Single crystals of γ-glycine have been grown by a slow evaporation solution growth technique (SEST) in presence of barium nitrate. The single crystal XRD confirms the hexagonal structure with the non-centrosymmetric space group P31. A high-resolution X-ray diffraction (HRXRD) rocking curve measurement reveals the good crystalline perfection. The linear refractive index estimated from the UV–Vis spectral data were fitted with Sellmeier’s equation and the refractive index was found to be constant (n≈2.55) over a wide range of wavelength. Hence, γ-glycine crystal can be used for optical waveguide applications. The relative SHG efficiency of γ-glycine crystal was studied by Kurtz and Perry powder technique. The third order nonlinear optical susceptibility was measured by Z-scan technique and the value was found to be χ(3)=9.06×10−6esu. The dispersion behavior of the linear refractive index was analyzed using the single oscillator model. The laser damage threshold value of γ-glycine crystal was estimated in single and multiple shot methods by using Nd:YAG laser.

Evidence of sustained ferroelectricity in glycine sodium nitrate single crystal

The nonlinear optical single crystals of glycine sodium nitrate were grown by the slow evaporation method. XRD confirmed monoclinic structure. Thermal stability and melting point (225 °C) were investigated. The dielectric behaviour of the crystals in the frequency range 20 Hz–2 MHz at different temperatures is reported in which a ferroelectric to paraelectric phase transition at Tc = 56 °C is observed. The activation energies of GSN were found to be 3.615 eV, 0.593 eV and 0.0733 eV in three temperature regions of conductivity plot due to a hopping conduction mechanism. The crystal has shown high piezoelectric charge coefficient (d33) of 16 pC/N which is nearly double of observed value for γ-glycine single crystal. The spontaneous polarization Ps at room temperature was found to be 1.489 μC/cm2 at applied maximum field of 26 kV/cm (1.194 μC/cm2 at 12 kV/cm) and the pyroelectric coefficient was determined to be 400 μC/m2/°C. High value of squareness parameter (1.93) makes the GSN crystal suitable for switching applications. Detailed investigations of Ferro-/Piezoelectricity were observed for the first time in glycine sodium nitrate crystals which was found to preserve the ferroelectricity even after applying an electric field much higher than the saturation electric field (12–26 kV/cm). Application of GSN crystals as sensor, high power switch gears and storage memories has been established.

Investigations on the nucleation kinetics of γ-glycine single crystal

Single crystals of γ-glycine were grown by slow evaporation technique. The crystalline system was confirmed by single crystal X-ray diffraction analysis. The optical absorption study has shown that the grown crystal possesses lower cut-off wavelength. Solubility and metastable zone width were estimated for different temperatures. The induction period of title compound was determined by varying the temperature and concentration. Nucleation parameters such as Gibbs volume free energy change (ΔGv), interfacial tension (γ), critical free energy change of the nucleus (ΔG⁎), nucleation rate (J), number of molecules in the critical nucleus (i⁎) have been calculated for the aqueous solution grown γ-glycine single crystals. The second harmonic generation (SHG) of γ-glycine was confirmed by Q-switched Nd:YAG laser technique.

Growth and characterization of γ-glycine single crystals from cadmium chloride for optoelectronic applications

Single crystal of γ-glycine, an organic nonlinear optical material has been grown by solvent evaporation technique from the aqueous solutions of glycine and cadmium chloride at ambient temperature for the first time. The γ-phase of glycine is confirmed by single crystal X-ray diffraction. The crystal is in hexagonal system with non-centrosymmetric space group P31. The FTIR spectral analysis shows the functional group vibration of γ-phase glycine. UV–vis–NIR analysis reveals that the crystal has good optical transparency window in the entire visible and IR region. UV cut-off wavelength is at ∼350nm. Thermal analysis shows the thermal stability, phase transition of the grown crystals and its melting point. Second harmonic generation efficiency of the crystal is about 1.7 times that of KDP.

Effect of zinc acetate addition on crystal growth, structural, optical, thermal properties of glycine single crystals

In the present study, γ-glycine has been crystallized by using zinc acetate dihydrate as an additive for the first time by slow solvent evaporation method. The second harmonic conversion efficiency of γ-glycine crystal was determined using Kurtz and Perry powder technique and was found to be 3.66times greater than that of standard inorganic material potassium dihydrogen phosphate (KDP). The analytical grade chemicals of glycine and zinc acetate dihydrate were taken in six different molar ratios: 1:0.2, 1:0.4, 1:0.6, 1:0.7, 1:0.8, and 1:0.9 respectively to find out the γ-polymorph of glycine. The lower molar concentration of zinc acetate yield only α-polymorph where as the higher molar concentration of zinc acetate inhibits the γ-polymorph of glycine which was confirmed by single crystal XRD and powder XRD studies. Inductively coupled plasma optical emission spectrometry (ICP-OES) was carried out to quantify the concentration of zinc element in the grown glycine single crystals. The concentration of zinc element in the presence of grown γ-glycine single crystal is found to be 0.73ppm. UV–Visible–NIR transmittance spectra were recorded for the samples to analyse the transparency in visible and near infrared region (NIR). The optical band gap Eg was estimated for γ-glycine single crystal using UV–Visible–NIR study. Functional groups present in the samples were identified by FTIR spectroscopic analysis. Differential scanning calorimetry technique was employed to determine the phase transition, thermal stability and melting point of the grown crystal.

Crystal growth, structural, optical, thermal and NLO studies of γ-glycine single crystals

In the present work, single crystals of γ-glycine possessing nonlinear optical properties were successfully grown at ambient temperature in the presence of sodium sulphate for the first time by using the slow evaporation method. Bulk growths of α-glycine and γ-glycine single crystal were grown by slow evaporation method and top-seeded solution growth method. The grown crystal was subjected to powder X-ray diffraction analysis to determine the characteristic peak of γ-glycine and lattice parameters. The chemical composition of the γ-glycine crystal was determined by elemental analysis. The results of the Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES) study show the presence of a small amount of sodium species in the grown γ-glycine crystal. The presence of functional groups was confirmed by FTIR spectroscopic analysis. The UV–vis–NIR spectrum indicates that the crystal has 75 percentage of transmittance in the entire visible and near IR region spectrum suggesting the suitability of the material for NLO applications. Differential scanning calorimetry (DSC) technique was employed to find the possible phase transition and to determine the thermal stability of γ-glycine. The second-order nonlinear optical property of the powdered sample of γ-glycine crystal was investigated by Kurtz and Perry powder technique and the relative second harmonic generation efficiency was found to be higher than that of standard inorganic material potassium dihydrogen phosphate (KDP).