Synthesis,crystal growth and characterization of a semiorganic material: Calcium dibromide bis(glycine) tetrahydrate

Single crystals of semiorganic material calcium dibromide bis(glycine) tetrahydrate were grown from aqueous solution. The crystal belongs to monoclinic system, with a = 13.261(5) Å, b = 6.792(2) Å, c = 15.671(9) Å and β = 91.68(4)°. The presence of the elements in the title compound was confirmed by energy dispersive X-ray analysis. The solubility and metastable zone width were found. The grown crystals were tested by powder XRD, FTIR, Thermo Gravimetric and Differential Thermal Analysis, UV–vis–NIR analysis, dielectrical and mechanical studies. The transmittance of calcium dibromide bis(glycine) tetrahydrate crystal has been used to calculate the refractive index n, the extinction coefficient K and both the real ɛ_r and imaginary ɛ_i components of the dielectric constant as functions of wavelength. The optical band gap of calcium dibromide bis(glycine) tetrahydrate is 3.23 eV.     

Synthesis,growth and characterization of L-proline dimercuricchloride single crystals for frequency conversion applications

A semi-organic nonlinear optical L-proline dimercuricchloride (LPDMC) material has been synthesized. LPDMC single crystals were grown from aqueous solution by a slow cooling method. Good quality single crystals of size 19×6×3 mm³ have been grown over a period of 3 weeks. The grown crystals have been subjected to single crystal X-ray diffraction analysis to determine the cell parameters. The title compound crystallizes in the triclinic system with a noncentrosymmetric space group P1 and with unit-cell parameters a=7.2742(4) Å, b=9.4472(5) Å, c=10.4767(6) Å, α=108.621(3)^°, β=107.260(2)^°, γ=97.353(2)^° and volume=631.51(6) Å³. Optical and dielectric properties of the crystals have been studied. The thermal stability of the crystals was determined by thermogravimetric analysis/differential thermal analysis. The second harmonic generation efficiency of the crystals was obtained by the classical powder technique using a Nd:YAG laser and it is found to be 2.5 times that of potassium dihydrogen phosphate.     

Experimental and theoretical studies on bis(glycine) lithium nitrate (BGLiN): A physico-chemical approach

Good quality and bulk size single crystal (size: 20×13×8 mm³) of bis(glycine) lithium nitrate (BGLiN) was grown by a slow evaporation solution technique from the aqueous solutions at constant temperature i.e. 27 °C using synthesized materials. Crystal system and lattice parameters were determined by single crystals as well as powder X-ray diffraction analysis. The lattice parameters of the titled compound are a=10.0223 Å, b=5.0343 Å, c=17.0510 Å, and V=860.312 Å³ and it crystallized in an orthorhombic system with space group Pca2₁ obtained by single crystal XRD. Elemental composition was confirmed by energy dispersive X-ray spectroscopic analysis. Optical absorption spectrum was recorded and various optical parameters such as optical transmission (~60%), and optical band gap (4.998 eV) were calculated. Photoluminescence study shows that the grown crystal is free from major defects. Crystalline perfection of the grown crystal was assessed and found good. Ground state optimized geometry has been obtained by using DFT with 6-31G(d,p) basis set. HOMO and LUMO energy gap was found to be 6.01 eV and dipole moment was 1.65 D.     

Enhanced properties of cadmium mercury thiocyanate bis(N-methyl formamide): A promising non-linear optical crystal

The present study deals with the synthesis and characterization of cadmium mercury thiocyanate bis(N-methyl formamide) or CMTN crystals where they were grown in two critical steps. In the first step, cadmium mercury thiocyanate (CMTC) single crystals were grown by intriguing cadmium chloride, mercuric chloride, and ammonium thiocyanate in 1:1:4 ratio and mixed with solvent by a slow solvent evaporation technique. The second step involves the reaction between CMTC and N-methyl formamide (NMF) in a 1:2 ratio leading to the formation of CMTN crystals. The growth parameters of CMTN grown crystals were optimized at different pHs (1- 5) and the solubility curve has also been reported. On characterization, the orthorhombic crystallinity having Pna2₁ space group of as-grown CMTN crystals has been revealed by single X-ray diffraction analysis (XRD) and the lattice cell parameters are found to be a = 15.195 Å, b =  7.722Å, c = 16.162 Å, and α = β = γ = 90°. Single the phase crystallinity of CMTN is observed by powder XRD pattern and the increase in the intensity of index peaks shows that there exists good coordination between the CMTC and NMF compounds. The FTIR analysis supported the presence of surface ligands groups of thiocyanate, while the Raman spectroscopy confirmed for the coordination of thiocyanate ions in the CMTN compound and thus both established for the metal-ligand bonding. The UV-vis spectroscopy showed the optical transparency of CMTN to have the cutoff wavelength at 335 nm and the Kurtz powder method for studying the second harmonic generation (SHG) output power is 5 times higher than the reference. Further increase of dielectric constant and dielectric loss with respect to the changes in frequency makes it a suitable material for the construction of photonic and non-linear optical (NLO) devices.     

Studies on the optical and mechanical properties of non-linear optical 3-aminophenol orthophosphoric acid (3-amphph) single crystal

Single crystals of semiorganic material 3-aminophenol orthophosphoric acid (denoted as 3-amphph) of size 29 × 17 × 4 mm³ have been grown by the slow evaporation of an aqueous solution of deionized water at 50 °C. The crystal belongs to orthorhombic system with the non centrosymmetric space group P2₁2₁2₁. The lattice parameter values of 3-amphph crystal are a = 4.481(2) Å, b = 9.782(4) Å and c = 18.326(4) Å. The grown crystals are subjected to single crystal XRD studies to identify its morphology and structure. Optical transmittance and second harmonic generation of the grown crystals have been studied by UV–Vis–NIR spectrum and Kurtz powder technique respectively. The transmittance of 3-amphph crystal has been used to calculate the refractive index n, the extinction coefficient k, reflectance R and both the real (?_r) and imaginary (?_i) components of the dielectric constant as a function of wavelength. The optical band gap of 3-amphph is 4.05 eV with direct transition. The anisotropic mechanical behavior of 3-amphph has been analyzed using Vickers microhardness test. The mechanism of growth is revealed by carrying out chemical etching using water as etchant.     

Optical and dielectric studies of solution grown glycinium maleate single crystal

Bulk single crystals of glycinium maleate have been grown from aqueous solution by slow evaporation method by optimizing the growth parameters within a period of 15 days. From X-ray diffraction analysis, the crystal was found to crystallize in monoclinic structure (space group C_2/c) with a = 17.866 Å, b = 5.684 Å, c = 17.408 Å and β = 112.65°. Presence of characteristic functional groups was confirmed in FTIR analysis. UV–Vis spectral analysis has revealed the absence of any high absorbance region between the wavelengths ranging from 300 to 900 nm. The optical band gap was calculated and found to be 3.91 eV. The activation energy for conduction at different frequencies was calculated and found to decrease from 0.54 eV to 0.41 eV as frequency increased from 100 Hz to 2 MHz. The dielectric behavior, conduction mechanism and the optical characterization of the glycinium maleate single crystals are being reported for the first time.     

Synthesis,growth and characterization of a semiorganic nonlinear optical single crystal: L-Valine cadmium bromide

A semiorganic nonlinear optical material L-valine cadmium bromide was synthesized and single crystal grown from an aqueous solution by the method of slow evaporation technique at room temperature. The grown crystal was characterized by Powder X-ray diffraction and FT IR studies. The LVCB crystallizes in monoclinic system with cell parameters a = 10.144(2) Å, b = 5.54(1) Å, c = 12.07(2) Å, β = 109.115(2)° with space group P₂₁. Thermal behavior and stability of crystal were studied using thermogravimetric analyses (TGA) and differential thermal analysis (DTA) techniques. The suitability of this material for NLO application was studied by optical absorption studies and second harmonic generation (SHG) efficiency measurement by Kurtz–Perry powder method.     

Crystal growth and characterization of a new co-ordination complex—barium tetrakis(maleate) dihydrate

Crystals of barium tetrakis(maleate) dihydrate [Ba₄(C₄H₂O₄)₄]^?2H₂O are grown in gelated hydrosilica matrix. Single crystal X-ray diffraction studies show that the crystal system is monoclinic with space group P2₁/c. The unit cell dimensions are a=9.3721(2)  Å, b=20.5880(7)  Å, c=14.0744(4) Å, α=γ=90°, β=90.289(2)°. Powder XRD studies confirmed the single phase nature of the grown crystals. The FTIR data is in conformity with the XRD results. The TG–DTA curves of the material indicate a three-step thermal decomposition. The response of the dielectric properties in the temperature range 30 °C to 500 °C is correlated with the TG–DTA results.     

Effective growth and characterization of piperazinium orthophthalate single crystal yielding high second harmonic generation efficiency

Good quality organic non-linear optical single crystal of piperazinium orthophthalate (PPA) was grown successfully by solution growth at room temperature by achieving the supersaturation state in slow evaporation method. The powder XRD analysis confirms the crystalline nature and structural parameters of the grown PPA crystal. The FTIR and Raman spectra confirm the existence of acid-base functional groups along with their vibrational mode exhibited, present in the grown PPA crystal. UV–Vis spectrum exhibits better transparency in the visible region with cut-off wavelength of 330 nm and the energy band gap (E_g) is analyzed to be 3.8 eV. Photoluminescence spectra shows good optical property with the excitation of 342 nm and two emission peaks in near edge UV band with blue emission at 364 and the energy transition in deep level defect states in crystals by exhibiting the green emission at 533 nm respectively. The thermal stability and the thermal absorption of the PPA crystal were identified by the TG - DTA analysis and obtained thermal stability was up to 88 °C. Vickers micro hardness test illustrates the mechanical stability of the grown PPA crystal and it belong to soft category (n = 4.6). Etching studies illustrates the growth pattern of the grown crystal using water as etchant. FE-SEM analysis shows the perfect smooth morphology of the grown PPA crystal. Second harmonic generation study illustrates the grown PPA crystal (λ = 532 nm) exhibit good nonlinear optical response.     

Structural and vibrational properties of PVT grown Bi2Te3 microcrystals

High-quality Bi₂Te₃ microcrystals have been grown by physical vapor transport (PVT) method without using a foreign transport agent. The microcrystals grown under optimal temperature gradient are well facetted and they have dimensions up to ～100 μm. The phase composition of grown crystals has been identified by X-ray single crystal structure analysis in space group R3?m, a=4.3896(2) Å, b=30.5019(10) Å, Z=3 (R=0.0271). Raman microspectrometry has been used to describe the vibration parameters of Bi₂Te₃ microcrystals. The FWHM parameters obtained for representative Raman lines at 61 cm^?1 and 101 cm^?1 are as low as 3.5 cm^?1 and 4.5 cm^?1, respectively.     

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 T_c = 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 P_s 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.     

Synthesis, growth and characterization of novel second harmonic nonlinear chalcone crystal

Nonlinear optical (NLO) materials are useful in many of the industrial applications. New NLO chalcone derivative (2E)-3-[4-(methylsulfanyl)phenyl]-1-(4-nitrophenyl)prop-2-en-1-one (4N4MSP) crystals have been grown by slow evaporation technique at ambient temperature. The grown crystals were subjected to single crystal X-ray diffraction study. The crystal has noncentrosymmetric structure in the orthorhombic system with space group Aba2 and unit cell parameters a=14.0647(15) Å, b=33.738(4) Å and c=6.0039(6) Å. To confirm the presence of various functional groups in the compound, FT-IR spectrum was recorded. The crystal was subjected to TGA/DTA analysis to find its thermal stability. The grown crystals were characterized for their optical transmission and mechanical hardness. The second harmonic generation (SHG) efficiency of the crystal is obtained by classical powdered technique using Nd:YAG laser and its value is 28.57 times that of urea. The laser damage threshold for 4N4MSP crystal was determined using Q-switched Nd:YAG laser. The refractive index values for green and red wavelengths were measured by Brewster angle technique. The dielectric and electrical measurements were carried out to study the different polarization mechanism and conductivity of the crystal. Good thermal, mechanical, transmission and SHG response make it desirable for the NLO applications.     

Synthesis and growth of sodium bitartrate monohydrate a new organometallic nonlinear optical single crystal

Sodium bitartrate monohydrate (SBTMH) a new organometallic nonlinear optical material, with molecular formula, [C₄H₅NaO₆ · H₂O] has been synthesized at ambient temperature. Spectral, thermal and optical techniques have been employed to characterize the new material. Bulk single crystals of size 13 × 4 × 4 mm³ of SBTMH have been grown by slow cooling method. The unit cell parameters of the grown crystal were determined by single crystal XRD. Functional groups present in the sample were identified by FTIR spectral analysis. Thermal stability of SBTMH was determined using TGA/DTA. The grown crystals exhibit nonlinear properties. The dielectric response of the crystal with varying frequencies was studied. The optical transparency range and the lower cut-off wavelength of the material were identified from the UV–vis–NIR absorption spectrum.     

Customizing optical and dielectric traits of ammonium dihydrogen phosphate (ADP) crystal exploiting Zn2+ ion for photonic device applications

Current investigation is aimed to explore the influence of Zn²⁺ ion on structural, optical and dielectric characteristics of ammonium dihydrogen phosphate (ADP) crystal to explore its widespread suitability for photonic device applications. The slow solvent evaporation technique has been adopted to grow the Zn²⁺ ion influenced ADP (Zn-ADP) crystal. The energy dispersive spectroscopic technique has been employed to determine the constituent elements of Zn-ADP crystal. The optical transmittance of pure and Zn-ADP crystal has been examined within 200–1100 nm by means of UV–visible spectral analysis. The Kurtz–Perry test has been employed to determine the enhancement in second harmonic generation (SHG) efficiency of ADP crystal due to presence of Zn²⁺ ion. The SHG efficiency of Zn-ADP crystal is found to be 3.15 times greater than potassium dihydrogen phosphate (KDP) and 1.79 times higher than ADP. The Z-scan analysis has been performed at 632.8 nm to study the third order nonlinear optical attributes (such as nonlinear refraction (n₂), absorption (β) and cubic susceptibility (χ³)) of Zn-ADP crystal. Dielectric analysis has been carried out within the temperature range of 30 to 90 °C to evaluate the effect of Zn²⁺ ion on dielectric constant and dielectric loss of ADP crystal. The thermal stability of the grown crystal has been investigated within the temperature range of 40–500 °C. The application of developed Zn-ADP crystal for photonic devices has been discussed in vision of obtained results.     

Growth,linear and nonlinear optical studies on guanidinium 4-nitrobenzoate (GuNB): An organic NLO material

Single crystals of guanidinium 4-nitrobenzoate (GuNB) were grown using solvent evaporation technique by mixing aqueous solutions of guanidine carbonate and 4-nitrobenzoic acid at ambient temperature. X-ray diffraction analysis characterized the unit cell parameters of the grown crystal and the crystal belongs to monoclinic system. The optical properties of the grown crystal have been studied by means of transmission measurements in the wavelength region between 200 and 1200 nm. The optical constants such as refractive index (n) and extinction coefficient (k) have been determined from the transmittance data. The optical band gap (E_g), the real and imaginary parts of the dielectric constant of the grown crystal was determined. Second harmonic generation (SHG) efficiency of the grown crystal has been studied using Nd:YAG laser and was measured as 3.2 times that of KDP. The low dielectric constant suggests the suitability of this compound material for NLO applications.     

Growth and characterization of a novel organic nonlinear optical material: l-alanine 2-furoic acid

l-alanine 2-furoic acid (LA2FA), a novel organic third order nonlinear optical material was grown by slow solvent evaporation technique at room temperature. The grown single crystals were characterized by XRD, spectral, thermal, optical, dielectric and third order nonlinear properties. LA2FA crystallizes into triclinic system with the space group P1. The cell parameters are found to be a = 3.97 Å, b = 7.09 Å, c = 10.69 Å, α = 73.61°, β = 83.57°, γ = 84.21° and V = 286 Å3. The modes of vibrations of different molecular groups present in LA2FA were identified by FTIR studies. The optical transparency of the grown crystals was investigated by UV–visible spectrum. The absorption spectrum reveals that the crystal has a high UV cut off of 245 nm and photonic band gap of 2.5 eV. The scanning electron microscope (SEM) study has been carried out to determine the surface morphology of the grown crystal. The thermal behavior of the crystal investigated using thermo gravimetric (TG) and differential thermal analysis (DTA) indicates that the material does not decompose before melting. The third order NLO property was studied in detail by z-scan technique.     

Studies on the optical and mechanical properties of organic nonlinear optical 1-(4-fluorostyryl)-4-nitrostilbene (FNS) single crystal

A new organic nonlinear optical material 1-(4-fluorostyryl)-4-nitrostilbene (FNS) has been synthesized and single crystals of FNS were grown using solvent evaporation solution growth technique (SESGT) by 2-butanon solvent. Single crystal x-ray diffraction analysis reveals the unit cell parameters of the grown crystal are a = 9.494(4) Å, b = 9.864(2) Å, c = 19.501(7) Å and it belongs to monoclinic system with noncentrosymmetric space group. Optical transmittance of the grown crystal has been studied by UV-Vis-NIR spectrum. The optical properties of FNS have been studied by means of optical transmittance measurements in the wavelength range of 190–1100 nm The optical constants were calculated from the optical transmittance (T) data such as refractive index (n), extinction coefficient (k) and reflectance (R). The optical band gap (E_g) of FNS is 3.27 eV with direct transition. The complex dielectric (?) constant of the grown FNS crystal was determined. The second harmonic generation (SHG) efficiency of the grown FNS crystal has been studied by using Kurtz-Perry powder technique and it shows 12 times relatively greater than KDP.     

Growth,structural, mechanical,spectral and dielectric characterization of NaCl-added Triglycine sulfate single crystals

Pure and sodium chloride (NaCl)-added Triglycine sulfate (TGS) crystals were grown from aqueous solutions by slow evaporation technique. The values of concentration of dopants in the mother solution were 0.2, 0.6 and 1 mol%. The solubility of the grown samples have been found out at various temperatures. The determination of unit cell parameters was carried out by single crystal XRD method and found that the grown crystals crystallize in monoclinic structure. The dielectric characterization for the pure and NaCl-doped TGS crystals was performed by measuring the dielectric parameters like dielectric constant and dielectric loss with various frequencies in the range 10²–10⁶ Hz and with the temperatures ranging from 30 to 70 °C and this study reveals an increase of dielectric constant and loss with the increase of NaCl concentration. Studies on mechanical properties like microhardness and density of the grown pure and NaCl-doped TGS crystals were carried out. UV–Visible transmittance studies were carried out for the grown samples. A sharp fall in the transmittance is observed at 228 nm for pure and NaCl-doped TGS crystals. Atomic absorption spectroscopic (AAS) study was done on the NaCl-doped TGS crystals to ascertain the presence of Na⁺ ions in the lattice.     

Growth of 4-(dimethylamino) benzaldehyde doped triglycine sulphate single crystals and its characterization

Single crystals of triglycine sulphate (TGS) doped with 1 mol% of 4-(dimethylamino) benzaldehyde (DB) have been grown from aqueous solution at ambient temperature by slow evaporation technique. The effect of dopant on the crystal growth and dielectric, pyroelectric and mechanical properties of TGS crystal have been investigated. X-ray powder diffraction pattern for pure and doped TGS was collected to determine the lattice parameters. FTIR spectra were employed to confirm the presence of 4-(dimethylamino) benzaldehyde in TGS crystal, qualitatively. The dielectric permittivity has been studied as a function of temperature by cooling the sample at a rate of 1 °C/min. An increase in the Curie temperature T_c=51 °C (for pure TGS, T_c=48.5 °C) and decrease in maximum permittivity has been observed for doped TGS when compared to pure TGS crystal. Pyroelectric studies on doped TGS were carried out to determine pyroelectric coefficient. The Vickers's hardness of the doped TGS crystals along (0 1 0) face is higher than that of pure TGS crystal for the same face. Domain patterns on b-cut plates were observed using scanning electron microscope. The low dielectric constant, higher pyroelectric coefficient and higher value of hardness suggest that doped TGS crystals could be a potential material for IR detectors.     

Synthesis, growth, and characterization of a non-linear optical crystal-glycine lithium chloride

A new non-linear optical material, glycine lithium chloride, was synthesized and single crystals were grown by slow evaporation solution growth technique at constant temperature from its aqueous solution. Transparent and well-crystallized hexagonal prisms were obtained by controlled evaporation at a constant temperature of 45 °C. The grown crystals were characterized by X-ray diffraction methods, Fourier transforms infrared spectroscopy, and optical absorption spectrum. Single crystal X-ray diffraction analysis revealed that the crystal lattice of glycine lithium chloride is hexagonal with unit cell a = b = 7.023 Å, c = 5.478 Å, α = β = 90°, γ = 120°, V = 234 Å³. The dielectric response of the crystal with varying frequencies was studied. The second harmonic generation efficiency of the crystal was studied and is found to be larger than KDP.