UV Vis NIR Spectrum Research Articles

Studies on growth and characterization of nonlinear optical L-tartaric acid–nicotinamide single crystal

Organic nonlinear optical (NLO) single crystal of L-tartaric acid–nicotinamide (LTN) has been grown by slow evaporation solution technique at a constant temperature of 40[Formula: see text]C. The grown crystals were subjected to various characterization techniques in order to examine their suitability for various applications. Powder X-ray diffraction (PXRD) analysis revealed that the compound is formed without any impurities. Functional groups and formation of the title compound were confirmed using FTIR analysis. Optical behavior of the material was examined using UV–Vis NIR spectrum analysis and the lower cut-off wavelength and optical band gap energy were calculated. Microhardness, dielectric and piezoelectric studies have been carried out at ambient conditions. Electronic properties such as valence electron plasma energy, Penn gap, Fermi energy and electronic polarizability were calculated by Clausius–Mossotti relation. Photoluminescence analysis was carried out to study the luminescence nature of the crystal and its defect states. In addition photoconductivity, etching studies and powder Kurtz and Perry second harmonic generation (SHG) test were carried out.

Pristine and cadmium-doped zinc oxide: chemical synthesis and characterizations

The chemical synthesis of pristine and cadmium-doped ZnO powders using a simple, cost-effective at 65 °C is reported and characterized for their structures, optical and morphological studies using X-ray diffraction, UV–visible–Near Infra-Red (UV–Vis–NIR) spectroscopy, scanning electron microscopy measurement techniques where XRD spectra confirm the formation of ZnO and Cd-doped ZnO with hexagonal crystal structure. The particle size of ZnO is reduced on Cd-doping from 16 to 14 nm. Plane-view surface morphology analysis supported for spherical-type crystallites and UV–Vis–NIR spectra reveal shift in the band edge of ZnO after Cd-doping. Photo-degradation study of Methylene Blue dye shows Pristine ZnO degrades dye faster than Cd-doped ZnO.

Structural, ferromagnetic and optical properties of pure bismuth A-site polar perovskite Bi(Mg3/8Fe2/8Ti3/8)O3 synthesized at ambient pressure

Bi(Mg3/8Fe2/8Ti3/8)O3 (BMFT) perovskite oxide ceramic has been synthesized by a conventional solid-state reaction method at ambient pressure. Structural characterization is detected by X-ray diffraction (XRD) and Raman spectroscopy, reflecting a polycrystalline perovskite structure. The peaks in XRD pattern shift toward lower angle, which indicates larger lattice constant than BiFeO3 (BFO). High frequency modes blue shift and the peak broadening can be observed clearly in micro-Raman spectroscopy compared with BFO patterns. Morphology analysis through scanning tunneling microscope shows dense and well-interlinked grains. Through the UV–Vis–NIR spectra, BMFT displays a narrow band gap of 2.23 eV, smaller than the 2.8 eV band gap of BFO. The room-temperature ferromagnetism of BMFT ceramic is measured for the first time, which can be attributed to the nonmagnetic ions of Mg2+ and Ti4+ ions replacing Fe3+ ions that causing the remanent magnetic moments. These results will open an avenue to further design multiferroic data storage and photovoltaic devices.

Characterization of potassium bromide crystals grown in the aqueous solution of picric acid

Potassium bromide crystals were grown in the aqueous solution of picric acid by slow evaporation technique at room temperature. X-ray Diffraction (XRD) analysis ensures that the grown sample is in Fm3m space group and FCC structure. Energy Dispersive X-ray Spectroscopy (EDX) reveals the presence of elements in the title compound. UV–Vis-NIR spectrum reveals that the grown sample is a promising nonlinear optical (NLO) material. FTIR analysis confirms the functional groups present in the sample. The thermogravimetric (TG) and differential thermogravimetric (DTA) analyses ensure that the sample material is thermally stable up to 160°C. The second harmonic efficiency of the sample is 1.3 times greater than that of standard KDP. The mechanical strength of the grown sample is estimated by Vickers microhardness tester. The electrical properties were investigated by impedance analysis and the results of various studies of the grown crystals are discussed.

High Second-Order NLO Response Exhibited by the First Example of Polymeric Film Incorporating a Diimine–Dithiolate Square-Planar Complex: The [Ni(o-phen)(bdt)

A novel square-planar diimine–dithiolate nonlinear optical (NLO) chromophore, the complex [Ni(o-phen)(bdt)] (1), is reported in this paper (o-phen = dianion of 1,2-phenylendiamina; bdt =1,2-benzenedithiolate). This compound has been fully characterized by single-crystal X-ray diffraction, UV–vis–NIR spectroscopy, cyclic voltammetry, DFT, and TD-DFT calculations. 1 crystallizes in the P21 space group and shows an almost planar molecule. The cyclic voltammetry measurements present an irreversible anodic peak at 0.87 V and reversible and quasi-reversible reduction waves at −0.35 and −1.13 V, respectively. A medium-intense (e = 1.91 × 104 mol–1 dm3 cm–1) absorption with a maximum at 728 nm appears in the UV–vis–NIR spectrum. The molecular second-order NLO properties of 1 have been measured by the electric field induced second-harmonic generation technique in DMF solution, giving values of −1000 × 10–48 esu for μβ1.907 and −356 × 10–48 esu for μβ0. Furthermore, remarkable solid-state responses have been measur...

Bulk crystals of L-Histidinium dihydrogen phosphate orthophosphoric acid grown by Sankaranarayanan–Ramasamy method

L-Histidinium dihydrogen phosphate orthophosphoric acid (LHDP) crystal of length 80mm long and 20mm diameter has been grown from aqueous solution along c-axis using Sankaranarayanan–Ramasamy method. The unit cell parameters were confirmed by single crystal X-ray diffraction analysis and it belongs to orthorhombic system. The UV–vis–NIR spectrum showed that the grown crystal is transparent in the entire visible region. The lower optical cut-off wavelength for this crystal was observed at 240nm. Fluorescence studies were carried out in range of 200–700nm. SHG efficiency was analyzed using Kurtz–Perry powder technique.

Growth of glycine ethyl ester hydrochloride and its characterizations

Single crystal of glycine ethyl ester hydrochloride by slow evaporation method is reported. The grown crystal characterized by single crystal X-ray diffraction, FT-IR, UV–Vis–NIR and fluorescence spectroscopy. It is established that the crystal falls under the monoclinic system and space group P21/c with the cell parameters as: a=8.565Å, b=12.943Å, c=6.272Å, α=γ=90°, β=103.630º. UV–Vis–NIR spectrum shows indirect allowed transition with a band gap of 5.21eV and other optical properties are measured. The crystal is also shown to have a high transmittance in the visible region. The third order nonlinear property and optical limiting have been investigated using Z-Scan technique. Complex impedance spectrum measured at the dc conductivity. Dependence of dielectric constant, dielectric loss and ac conductivity on frequency at different temperature of applied ac field is analyzed. The mechanical behavior has been assessed by Vickers microhardness indenter. The thermal behavior of glycine ethyl ester hydrochloride was analyzed using TG/DTA thermal curves. From the thermal study, the material was found to possess thermal stability up to 174°C. The predicted NLO properties, UV–Vis transmittance and Z-scan studies indicate that is an attractive material for photonics optical limiting applications.

Physical and chemical properties of the ancient glass beads from the highland log-coffin culture and the lowland areas, Thailand: Considerations on their colors and technology

The ancient glass beads from a log coffin cave at Pang Mapha, Mae Hong Son as well as from Sa Kaeo, Thailand, were studied for their physical and chemical properties. The samples have an average specific gravity of 2.25, and an average refractive index of 1.55. The glasses show typical inclusions of swirls and gas bubbles, suggesting drawn production. Copper and iron are the main sources of the blue and green glasses, confirmed by the UV–Vis–NIR spectra, whereas the lead stannate is responsible for the yellow and iron for the black beads. Lead, as a color intensifier, is dominant in a gradual change from yellow to green, to blue samples, respectively. The main raw materials could possibly be silica sand, reh, and stannate. There are some evidences indicating recycled raw materials. We found that people on the northern highland of the log coffin culture had a connection to the low land community in the central and eastern regions of the country during the years of ~260–560CE. The technology of glass making for the studied glasses is the same as those used in the Dvaravati Kingdom glasses found in the sites of central Thailand.

Spectral and microscopic study of self-assembly of novel cationic spermine amides of betulinic acid

Supramolecular characteristics of two spermine amides of betulinic acid (1 and 2) were studied by measuring and evaluating their UV–VIS-NIR spectra in aqueous acetonitrile and DOSY-NMR spectra in tetradeuteromethanol, accompanied by atomic force microscopy (AFM) images, scanning electron microscopy (SEM) micrographs, and transmission electron microscopy (TEM) micrographs. Fibrous supramolecular self-assembly of 1 and 2 was observed by AFM images, as well as by the SEM and TEM micrographs. Bathochromic shifts of the absorbance maximum at 870nm to 1015–970nm in the UV–VIS-NIR spectra were observed with increasing water content in the acetonitrile/water systems, indicating formation of fibrous J-type aggregates. Variable temperature DOSY-NMR spectral measurement showed non-linear dependence that also suggests self-assembly behavior of the studied systems. Chiral supramolecular structures were formed by self-assembling due to the chirality of the monomeric molecules. Application of aqueous media during self-assembly procedures is an important factor in the development of targeted drug delivery systems.

Judd-Ofelt intensity parameters of samarium-doped magnesium zinc sulfophosphate glass

Achieving better performing glasses with modified optical properties for short-wavelength solid state lasers is demanding. Inspired by this fact, Samarium (Sm3+)-doped glass of the magnesium zinc sulfophosphate system with composition (60-x)P2O5-20MgO-20ZnSO4-xSm2O3 (x=0, 0.5, 1, 1.5 and 2mol%) was prepared using the melt-quenching technique. The samples are thoroughly characterized to determine the influence of varying Sm3+ ion contents on their spectral properties. UV–Vis-NIR spectra revealed the occurrence of several absorption bands corresponding to the transitions from the ground state to various excited states of the Sm3+ ion. Judd-Ofelt (JO) spectral analyses were carried out to determine the local structure and bonding in the vicinity of Sm3+ ions. The experimental oscillator strengths calculated from the absorption spectra are used to evaluate three phenomenological JO intensity parameters Ωi(i=2, 4 and 6). The Sm3+ ions' assisted modification in the overall glass properties is ascribed to the alteration in glass network structures. Quantities such as radiative transition probabilities, radiative lifetime, branching ratios and stimulated emission cross-sections are calculated for the 4G5/2→6HJ (J=5/2, 7/2, 9/2 and 11/2) transitions of Sm3+ ions. The PL spectra displayed four prominent emission bands centered at about 562, 599, 644 and 702nm with intensity quenching beyond 1.5mol% of Sm3+ ions. Our results are analyzed using various mechanisms and compared to previous reports. Our findings may be beneficial for the advancement of functional glasses.

Synthesis, crystal growth and characterizations of bis (l-proline) cadmium iodide: a new semi-organic nonlinear optical material

Novel semi-organic single crystals of bis (l-proline) cadmium iodide (BLPC) were grown by slow evaporation technique. The crystal structure was determined by single-crystal X-ray diffraction studies. Single-crystal X-ray diffraction study shows that [BLPC] crystallizes in orthorhombic system with space group P212121. 1H NMR and 13C NMR studies were conducted for the grown crystal. Functional groups present in the compound were identified by FTIR spectral studies. The UV–Vis–NIR spectrum was studied to analyse the optical properties of the grown crystals. Thermogravimetric analysis was carried out to study thermal behaviour of the materials. Vickers microhardness measurement was carried out for different loads. Etching studies were carried out using water as etchant. The second harmonic generation efficiency was determined by the Kurtz powder method and it was found to be higher than that of potassium dihydrogen phosphate.

Growth, optical, thermal, mechanical and dielectric studies of sodium succinate hexahydrate (β phase) single crystal: A promising third order NLO material

A third order nonlinear optical (NLO)single crystals of sodium succinate hexahydrate (SSH) (β phase) has been grown by a slow evaporation growth technique using aqueous solution at ambient temperature. The lattice parameters and morphology of SSH were determined by single crystal X-ray diffraction analysis. SSH crystallizes in centrosymmetric monoclinic system with space group P21/c and the crystalline purity was analyzed by powder X-ray diffraction analysis. The UV–vis–NIR spectrum reveals that the crystal is transparent in the entire visible region. The recorded FT-IR spectrum verified the presence of various functional groups in the material. NMR analysis of the grown crystal confirms the structural elucidation and detects the major and minor functional groups present in the title compound. ICP-OES analysis proved the presence of sodium in SSH. TG-DTA/DSCanalysis was used to investigate the thermal stability of the material. The dielectric permittivity and dielectric loss of SSH were carried out as a function of frequency for different temperatures and the results were discussed. The mechanical stability was evaluated from Vicker's microhardness test. The third order nonlinear optical properties of SSH has been investigated employing Z-scan technique with He-Ne laser operating at 632.8nm wavelength.

Studies on the optical, thermal, electrical and dielectric properties of 5-chloro-2(3H)benzoxazolone Picrate: a new nonlinear optical crystal

An organic single crystals of 5-chloro-2(3H)benzoxazolone Picrate (5C2BP) were grown by slow evaporation of solvent technique at ambient temperature using water and ethanol as mixed solvent. The grown 5C2BP crystals were subjected to single crystal XRD and powder XRD to know the unit cell parameters and crystallinity of the sample. Fourier transform infrared spectrum of the grown crystal confirmed the presence of various functional groups in the material. UV–vis–NIR spectrum was used to investigate the optical transparency of the grown crystal. Thermal behaviour was studied by thermogravimetric and differential thermal analysis and melting point was determined by differential scanning calorimetry. The frequency dependence of dielectric properties with different temperature and the DC electrical conductivity with different temperature was performed on the grown crystal. The nonlinear optical property was confirmed by second harmonic generation test using Nd:YAG laser of fundamental wavelength 1064 nm.

Synthesis, growth and characterization of (tri) glycine barium chloride single crystal for applications in the domain of optoelectronics and photonics

The single crystal of (tri) glycine barium chloride, a semiorganic crystal has been grown from an aqueous solution by slow evaporation technique at room temperature. Glycine and barium chloride were used in molar ratio of 3:1 for synthesis. Good optical quality single crystal of size 18 × 10 × 5 mm3 was harvested in a period of 5 weeks (35 days) at pH value 5. The lattice parameters have been measured by single crystal XRD study. The crystalline nature has been confirmed by powder XRD study. Fourier transform infrared spectroscopy study confirmed the presence of functional groups in grown crystal. Transmission spectrum has been recorded and the cut-off wavelength has been determined as 234 nm. Also optical constants like band gap, refractive index, reflectance, extinction coefficient and electric susceptibility were determined from UV–Vis-NIR spectrum. The thermal behavior of the crystal was investigated by TG–DTA analysis, which reveals that crystal has thermally stable up to 169 °C. Non-linear optical property of the grown crystal has been confirmed using the Kurtz and Perry powder technique and result was compared with KDP. The dielectric behavior of the sample was analyzed with various frequencies at different temperatures. The photoconducting nature of the crystal was analyzed by photoconductivity study.

Bulk growth and characterization of novel organic piperazinium (bis) hydrogen succinate single crystals

The new organic nonlinear optical material piperazinium (bis) hydrogen succinate single crystal (PPHS) was synthesized by the slow evaporation method. The solubility of PPHS was determined by gravimetric analysis and the metastable zonewidth was assessed by polythermal method. The induction period was measured by isothermal method. The experimentally calculated values of the interfacial energies are in agreement with the theoretical values. As an outcome of studying the nucleation parameters, a bulk single crystal of PPHS was grown by slow cooling method. The structure of PPHS was estimated from single crystal X-ray diffraction analysis. FT NMR spectrum was analyzed. The cut - off wavelength and energy band gap values were found to be 254nm and 4.85eV respectively from the UV–vis–NIR spectrum analysis. The thermal stability of the grown crystal was studied. The mechanical strength and third order nonlinear optical susceptibility of the grown crystal were measured by Vicker's microhardness test and Z-scan technique respectively.

Growth of divalent Mn2+ metal ion-doped potassium acid phthalate (KAP) single crystals and its structural, spectroscopic, optical and mechanical properties for SHG device applications

Divalent Mn2+ ion-doped potassium acid phthalate (KAP), a semi-organic non-linear optical (NLO) single crystals were grown by slow evaporation solution technique (SEST) at ambient temperature. Good optical quality single crystals of size 5 × 6 × 5 mm3 were grown in a period of 1 week. The pure and Mn2+ ion-doped KAP crystals were characterised by single-crystal X-ray diffraction (XRD) analysis to study the crystal structure. Single-crystal XRD analysis confirmed that the doped KAP crystallises in orthorhombic system with the space group Pca21. Powder X-ray diffraction (XRD) has confirmed the formation of the dopant in the KAP crystal. The functional groups of the grown crystals were identified by Fourier transform infrared spectrum (FTIR). UV–Vis NIR spectrum was recorded to study the optical transparency of the grown doped KAP crystals. The mechanical strength of the crystal is estimated by Vickers microhardness test. The stiffness constant and work hardening co-efficient were also calculated. The second harmonic generation (SHG) efficiency for device application was confirmed by NLO studies.

Effect of fluence on carbon nanostructures produced by laser ablation in liquid nitrogen

Effects of laser fluence on the properties of carbon nanostructures produced by laser ablation method in liquid nitrogen have been studied experimentally. The beam of a Q-switched Nd:YAG laser of 1064-nm wavelength at 7 ns pulse width and different fluences is employed to irradiate the graphite target in liquid nitrogen. Properties of carbon nanostructures were studied using their UV–Vis–NIR spectrum, TEM images, and Raman scattering spectrum. Two categories of graphene nanosheets and carbon nanoparticles were observed due to variation of laser fluence. Results show that in our experimental condition there is a threshold fluence for producing carbon nanoparticles. With increasing the laser fluence from the threshold, the amount of carbon nanoparticles in suspensions was increased, while the amount of graphene nanosheets was decreased.

A study on the linear and nonlinear optical properties of Li and NH4 doped potassium pentaborate crystals

In this letter, we report on the linear and nonlinear optical investigations of 5mol% of Li, NH4 doped potassium pentaborate (KB5) crystal. Doping concentration was quantified by the EDAX and ICP analysis. The enhancement of transparency in the doped crystals was recorded in UV–vis–NIR spectra. Optical band gap of the pure and doped crystals was also calculated. The optical nonlinearity of the grown crystals was confirmed by Second Harmonic Generation (SHG) test which shows that the dopants in the KB5 crystal enhanced the SHG efficiency of that material. The third order nonlinearity was studied by Z- scan technique using 632.8nm He-Ne laser. The values of nonlinear absorption coefficient (β) and nonlinear refractive index (n2) were calculated. Third order nonlinear susceptibility (χ(3)) of the Li and NH4 doped crystals is 1.0278×10−3esu and 0.7744×10−3esu respectively which is higher than that of pure KB5 (0.6770×10−3esu).

Determination of toxic carbonyl species including acetone, formaldehyde, and phosgene by polyaniline emeraldine gas sensor using DFT calculation

Detection of toxic carbonyl gases such as acetone, formaldehyde, and phosgene by polyaniline emeraldine salt (PANI ES) was theoretically investigated using the UB3LYP/6-31G(d) level of theory. Sensing potentials of nPANI ES (n=2, 4, 6, and 8) complexed with toxic carbonyl gases were described in terms of structural, electronic, and optical properties. We found that HOMO-LUMO gaps of PANI ES after response to toxic carbonyl compounds are decreased, revealing higher electron delocalization and conductivity along backbone of PANI ES complexes compared with bare PANI ES. Phosgene shows the highest conductivity followed by formaldehyde and acetone, respectively, while reverse tendency was detected for interaction energies. UV–vis-NIR spectra estimated by means of TD-UB3LYP/6-31G(d) method of PANI ES complexes are all blue-shifted compared to their intrinsic structures, confirming the n-type doping process. The amount of blue-shift for acetone sensing is distinctly higher than those observed for formaldehyde and phosgene. These obtained results not only revealed a conductivity enhancement of polyaniline emeraldine salt sensing with toxic carbonyl gases but also demonstrated an ability to determine such toxic gases by utilizing optical measurement.

Structure, growth and characterization of picolinium perchlorate single crystals

Picolinium perchlorate organic single crystals were grown using slow evaporation solution growth technique at room temperature using water as a solvent. The structure of the title compound was supported by proton NMR analysis and the single crystal X-ray diffraction data. Crystallographic studies revealed that the compound crystallized in monoclinic system with space group C2/c. The HRXRD rocking curve measurements revealed the crystalline perfection of grown crystal. First order hyperpolarizability, HOMO and LUMO energies are calculated using Density Functional Theory (DFT) with a hybrid functional B3LYP and the 6-311++G(d,p) basis set. Global reactivity indices are calculated. Thermal studies were carried out on the title compound. The UV–vis–NIR spectrum was recorded to study the optical transparency of the grown crystals. The mechanical stability of the crystal was analyzed by Vicker's microhardness studies.