NLO Characteristics Research Articles

Spectroscopic, quantum mechanical, electronic excitation properties (Ethanol solvent), DFT investigations and molecular docking analysis of an anti-cancer drug Bendamustine

In this investigation, optimization geometry of the molecule, FT-IR, FT-Raman, and UV-Vis spectra, vibrational frequencies, assigning of suitable vibrational modes of Bendamustine (an anti-cancer drug) were summarised on the grounds of distribution of potential energy. Spectroscopic investigations are attempted by employing DFT/B3LYP with 6-311++G (d, p) level. The output of the computations was implemented to model the spectra of the Bendamustine, which agrees well with the recorded spectra. The TDFT had been utilized to compute the strengths of oscillators. To ascertain the transfer of charge inside the molecule HOMO and LUMO analytics have been utilized. The NBO investigation has been employed to verify the stability of the molecule by observing internal charge transfer, hyperconjugation, and energy of stabilization. Molecular electrostatic potential and Mulliken's charges were thoroughly studied by using DFT methods. The NLO characteristics of the title drug molecule were investigated with B3LYP and HF basis functionals. The reactive sites and reactivity of the title drug molecule have been extensively studied with help of condensed Fukui functions and global descriptors. The molecular docking investigations of the title drug molecule were executed with the DNA binding protein of Cellular Tumour Antigen P53.

Boosted Electronic, NLO and Absorption Characteristics for Quercetin and Taxifolin; Comparative Experimental and DFT Studies

In the present study, a considerable, reproducible, and eco-friendly biological synthesis of Ag nanoparticles using Mangifera indica leaf extract as a reductant is documented. The spectroscopic characteristics of synthesized Ag nanoparticles are described by both UV-Vis and FT-IR techniques. The bandgap offsets, reactivity, and NLO properties for two flavonoids, quercetin, and taxifolin, are examined using the DFT approach. Also, a detailed comparative analysis for HOMO-LUMO interactions among quercetin and taxifolin is discussed. Results show that quercetin and taxifolin possess dipole moment (DM=4.79, 3.99 Debye) and bandgap offset (2.59, 2.98 eV). Both molecules are promising candidates as window layers for solar cells and memory switch devices. In addition, hyperpolarizability calculations show that quercetin NLO response is higher than taxifolin, which sets a revolutionary recall for NLO manufacture upgrade. Moreover, NBO and UV-Vis absorption characteristics are reported as well.

Boosted Electronic, NLO and Absorption Characteristics for Quercetin and Taxifolin: Comparative Experimental and DFT Studies

In the present study, a considerable, reproducible, and eco-friendly biological synthesis of Ag nanoparticles using Mangifera indica leaf extract as a reductant is documented. The spectroscopic characteristics of synthesized Ag nanoparticles are described by both UV-Vis and FT-IR techniques. The bandgap offsets, reactivity, and NLO properties for two flavonoids, quercetin, and taxifolin, are examined using the DFT approach. Also, a detailed comparative analysis for HOMO-LUMO interactions among quercetin and taxifolin is discussed. Results show that quercetin and taxifolin possess dipole moment (DM=4.79, 3.99 Debye) and bandgap offset (2.59, 2.98 eV). Both molecules are promising candidates as window layers for solar cells and memory switch devices. In addition, hyperpolarizability calculations show that quercetin NLO response is higher than taxifolin, which sets a revolutionary recall for NLO manufacture upgrade. Moreover, NBO and UV-Vis absorption characteristics are reported as well.

Structural parametersversusthird-order optical susceptibility of zinc porphyrin molecules

Third-order NLO properties of Zn porphyrins are correlated to their structures by combining experiments and DFT calculations adopting six strategies. Molecules of lesser π-electron conjugation are also shown to have higher NLO characteristics.

Considerations on electrochemical behavior of NLO chromophores: Relation of redox properties and NLO activity

Data provided by electrochemical studies are of particular interest for nonlinear optical chromophores being used to predict the properties and search more effective donor-acceptor systems. Based on voltammetric experiments (CV, DPV), one can estimate the HOMO and LUMO energy gap and correlate it with the structure, analyze solvatochromic effects, and obtain additional important information about changes in the energy of each molecular orbital, and not only the gap itself (an advantage over optical methods). Also, the location of the gap relative to the energy axis (electrochemical electronegativity) allows to identify the more hyperpolarizable chromophores. This review summarizes the results obtained in recent years in the field of chromophore electrochemistry elucidating the relationship between molecular NLO characteristics predicted on the basis of quantum-chemical calculations (the hyperpolarizability) and energy characteristics of promising chromophores.

The study and comparison of power-dependent nonlinear optical behaviours of α-mangostin with Sheik-Bahae formalism and thermal lens model using Z-Scan technique

The pericarp of Garcinia mangostana (mangosteen) contains α -mangostin (α -MG), which is an essential compound derived from the family of xanthone. This study aimed to determine the nonlinear optical response of the extracted α -MG using Z-scan technique (532 nm, 0.5–1.0 W). A series of characterisations were also done by using 1H &13C nuclear magnetic resonance (NMR), electron impact mass spectrometry (EIMS), ultraviolet-visible (UV–vis) and Fourier transform infrared (FTIR) to validate the identity of the extracted α -MG. The results showed that only nonlinear refraction (NLR) was successfully captured and measured by the closed-aperture signal. The localized absorption across the media enabled the α -MG to exhibit a self-defocusing effect. The recorded values of the nonlinear refractive index, which were denoted as n2, were then compared with two different theoretical fitting curves, which were Sheikh-Bahae Formalism (SBF) and Thermal Lens Model (TLM). The values of n2 obtained were in the order of 10−9 and 10-10 for SBF and TLM, respectively. The NLO characteristics of the α -MG were observed at the excitation wavelength of 532 nm.

Electronic and NLO characteristics of small neutral and singly charged iron-doped bismuth clusters

The electronic and optical properties of the iron-doped bismuth nanoclusters having less than 15 atoms are presented here. This doping is especially interesting since it enhances the stability and magnetic properties of the bismuth clusters, as shown here. The effect of singly charging the clusters on their stability and electronic properties is also investigated. Binding energy analysis shows that iron doping enhances the relative stability of the small bismuth clusters. An almost regular pattern is observed for the maximum Raman peak of the first five clusters and the succeeding nine clusters. An oscillating magnetic moment behavior is observed for the neighboring bismuth numbers from 5 to 11. Singly charged clusters also show similar magnetic characteristics. HOMO-LUMO energy gap also follows the expected pattern of the quantum confinement as larger clusters demonstrate the smaller difference between these two levels. Interestingly, this general downward trend falls in the range of visible light. The projected density of states (PDOS) also confirms the obtained results for the energy gap. The charge distribution behavior shows negative charge accumulation on iron atoms except for the case of FeBi.

Pyrazolylmethylenepyrimidinetrione: Synthesis, Characterization and DFT Analysis

A barbituric acid tailored pyrazole chemical entity 1f was synthesized and characterized utilizing analytical and various spectroscopic techniques. Further the molecular properties of the molecule such as optimized structure, FMO analysis, electrostatic potential, Mulliken charges, and NLO characteristics were determined by subjecting 1f in to DFT calculations employing B3LYP method. The outcome imply that the target could be served in one direction as biologically important molecule/intermediate and the other direction as NLO material / an intermediate to construct better NLO materials.

Z-scan and DFT approach for investigating the NLO properties of imidazole fused anthraquinone dyes

The NLO characteristics of anthraquinone imidazole-fused D-π-A dyes were investigated by Z-scan and density functional theory (DFT) methods. The electronic and photophysical studies i.e. the intramolecular charge transfer (ICT) characteristics were demonstrated by UV-visible analysis, cyclic voltammetry (CV) study, frontier molecular orbital (FMO), molecular electrostatic potential (MEP) and quinoidal character. Thermogravimetric analysis (TGA) of the dyes 2-(9-phenyl-9H-carbazol-3-yl)-3H-anthra[1,2-d]imidazole-6,11-dione (AQ CBZ) and 2-(4-(diphenylamino)phenyl)-3H-anthra[1,2-d]imidazole-6,11-dione (AQ TPA) revealed high thermal stability. The dye AQ TPA demonstrated strong ICT character with high nonlinear susceptibility χ(3) = 3.50×10−13 e.s.u. The dye AQ CBZ 4.40 J cm−2 showed better optical limiting data relative to AQ TPA. The NLO properties of AQ CBZ and AQ TPA were computed using different DFT functionals with varying Hartree Fork (HF) exchange. The dye AQ TPA revealed superior NLO properties in all the used functionals comparative to AQ CBZ. The long-range corrected (LC) functionals (CAM-B3LYP, ωB97 and ωB97X) exhibited almost equivalent NLO properties as proportional to global hybrid functionals (B3LYP, PBE0, BHHLYP and, M06-HF). The calculated NLO properties were correlated with the reference dye. The DFT findings were appropriately correlated with Z-scan results.

Effects of optical and dielectric properties of l-cysteine doped tris thiourea zinc sulphate single crystals

The nonlinear optical single crystals of pure and l-cysteine amino acid doped Tris Thiourea Zinc Sulphate (TTZS) was synthesized and successfully grown by slow solvent evaporation technique. The present crystal was characterized by various analytical techniques. The lattice parameter values, cell volume and structure of the present crystal were identified by single crystal X-ray diffraction technique. The optical transparency and lower cut-off wavelength has been observed by UV–Vis spectrometer and further optical parameters were calculated. The FTIR analysis reveals the presence of functional groups and the kinds of vibrations. The NLO characteristics and laser damage threshold can be determined using Nd: YAG laser. The NLO efficiency and laser induced damage value of the L-cysteine doped tris thiourea zinc sulphate single crystal was found to be greater than pure TTZS crystal. In PL spectrum, sharp and narrow peaks are identified it denoted that the material having multi emission and it is suitable for applications in the light emitting diodes. The energy corresponding to the particular wavelength is also calculated. Growth nature of the title crystal was observed by etching analysis. The strength of the pure and doped crystals was determined using Vicker’s micro hardness test.

Synergetic effect of Ag/PVP on nonlinear optical characteristic of rGO transparent thin films

Reduced graphene oxide (rGO)-based transparent thin films including rGO, rGO/PVP and rGO/PVP/Ag (TFs) were prepared by drop casting method. The reduction process was performed using HI vapor. The physicochemical, morphological and structural characteristics of the prepared samples were studied using different characterization methods such as X-ray diffraction analysis, scanning electron microscopy and Raman spectroscopy. The linear and nonlinear optical properties of prepared samples were evaluated by Z-scan technique using a He–Ne laser (632 nm), respectively. Results showed that the nonlinear refraction index (n2) and nonlinear absorption coefficient (β) of the prepared rGO/PVP thin film are higher than that reported before. Adding Ag NPs caused a considerable improvement in the NLO characteristics of rGO/PVP.

Experimental and theoretical investigation on 2-amino 5-bromopyridinium L-tartrate-A new organic charge-transfer crystal for optoelectronics device applications

A new organic charge transfer (CT) complex of 2-amino 5-bromopyridinium L- tartrate (2A5BPTA) has been synthesized successfully and single crystals were grown by conventional slow evaporation solution technique (SEST). Single crystal X-ray diffraction analysis reveals that 2A5BPTA crystallized in orthorhombic system with noncentro symmetric space group P212121. The various vibrational modes in the crystal were confirmed by FTIR analysis. Optical transmission analysis shows that 2A5BPTA is transparent in the entire visible region of electromagnetic spectrum. Spectral dependence of optical birefringence study was carried out over the wavelength range of 480–620 nm for the crystal thickness of 0.141 mm. Thermal behaviour of the grown crystal has been studied using thermogravimetric and differential thermal analysis. Dielectric studies were carried out for the grown crystal at a different temperature. Photoconductivity study shows that evidence of positive photoconducting nature at room temperature. The NLO characteristics and phase matching ability were explored by powder second harmonic generation studies. Phase matching studies were elucidated for the titled compound. The first order hyperpolarizability investigation was performed using the Gaussian 09 program with B3LYP method.

Vibrational, NMR and UV–visible spectroscopic investigation and NLO studies on benzaldehyde thiosemicarbazone using computational calculations

In order to investigate the vibrational, electronic and NLO characteristics of the compound; benzaldehyde thiosemicarbazone (BTSC), the XRD, FT-IR, FT-Raman, NMR and UV–visible spectra were recorded and were analysed with the calculated spectra by using HF and B3LYP methods with 6-311++G(d,p) basis set. The XRD results revealed that the stabilized molecular systems were confined in orthorhombic unit cell system. The cause for the change of chemical and physical properties behind the compound has been discussed makes use of Mulliken charge levels and NBO in detail. The shift of molecular vibrational pattern by the fusing of ligand; thiosemicarbazone group with benzaldehyde has been keenly observed. The occurrence of in phase and out of phase molecular interaction over the frontier molecular orbitals was determined to evaluate the degeneracy of the electronic energy levels. The thermodynamical studies of the temperature region 100–1000K to detect the thermal stabilization of the crystal phase of the compound were investigated. The NLO properties were evaluated by the determination of the polarizability and hyperpolarizability of the compound in crystal phase. The physical stabilization of the geometry of the compound has been explained by geometry deformation analysis.

Growth and characterization of NLO crystal: L-leucine phthalic acid potassium iodide

Abstract A new semi-organic non linear optical crystal, L-leucine phthalic acid potassium iodide (LLPPI) has been grown from an aqueous solution by slow evaporation method. The grown crystals were subjected to different characterizations, such as single crystal XRD, FT-IR, UV-Vis, TGA, SEM, EDAX, micro hardness, dielectric and powder SHG. Single crystal structure was determined from X-ray diffraction data and it revealed that the crystal belongs to triclinic system with the space group P1. The vibrational frequencies of various functional groups were derived from FT-IR spectrum. Thermal stability of the grown crystal was investigated by TG-DTA studies and it was observed that the crystal was thermally stable up to 192 °C. Optical absorption study was carried out and a good transparency in the entire visible region was observed at the lower cutoff wavelength of 227 nm. Dielectric study was performed as a function of frequency and normal dielectric behavior was observed. The micro hardness test was carried out and the load dependent hardness was measured. Kurtz powder method was employed to explore the NLO characteristics of the grown crystal.

Comparative Spectroscopic Studies on Pure, 10 and 50 mol% Glycine Mixed L-Valinium Picrate Crystals

Nonlinear optical crystals of pure, 10 and 50 mol% glycine mixed L-valinium picrate have been grown from saturated aqueous solution by slow evaporation method at a temperature of 36℃ using a constant temperature bath of accuracy of ±0.01℃. The synthesized organic optical material has been purified by repeated recrystallization. The cell parameters were calculated using single crystal X-ray diffraction technique which confirmed the crystal system. Optical behavior was examined by UV-Vis-NIR spectrometer in the range from 190 nm to 1100 nm, which revealed the absence of absorption in the entire visible region. Functional groups and modes of vibration were identified by FT-IR spectrometer in the range between 400 cm-1 and 4000 cm-1. The 1H- and 13C NMR spectra of grown crystals were recorded using D2O as solvent on a Bruker 300 MHz (Ultrashield) TM instrument at 23℃ (300 MHz for 1H NMR and 75 MHz for 13C NMR) to confirm the molecular structure. The second harmonic generation conversion efficiency was investigated by Kurtz powder method using Nd: YAG laser as a source to explore the NLO characteristics.

Investigations on the physico chemical properties of 4-bromochalcone single crystals for nonlinear optical applications

Good quality yellow transparent single crystals of 4-bromochalcone (4BC) crystal have been synthesized and grown by slow evaporation solution growth method. The UV–Vis spectra was recorded for the grown crystal. The thermal behavior of the title crystal was studied. Fourier transform infrared and Raman spectral studies were performed for analyzing and assigning the vibrations and to identify the functional groups. The relative SHG efficiency of the material was investigated to explore the NLO characteristics for the first time in the literature. The SHG efficiency of the material is found to be 1.14 times greater than urea. Hyperpolarizability and HOMO–LUMO analysis of 4-bromochalcone (4BC) were performed with the help of Density Functional Theory (DFT) calculations using Gaussian 03 software.

Synthesis, growth and characterization of a novel semiorganic NLO crystal: Triglycine calcium dibromide

Triglycine calcium dibromide, a new semiorganic nonlinear optical material, has been grown by slow solvent evaporation technique for the first time. The size of the grown crystal is up to the dimension of 20×12×4 mm3. They were characterized by single crystal X-ray diffraction for confirming the coordination formed and FTIR spectral analysis for identifying the functional groups present in the compound. Optical behavior such as UV–vis–NIR transmission spectrum and second-harmonic generation were investigated to explore the NLO characteristics of the material. Thermal analysis was carried out to determine the melting point and the thermal stability of the grown crystal. Dielectric constant and dielectric loss measurements were carried out at different temperatures and frequencies. Mechanical studies were carried out on the as-grown crystal to find Vicker’s microhardness and yield strength. Laser damage threshold studies were also performed on the as-grown crystal.

The polarizability in solution of tetra-phenyl-porphyrin derivatives in their excited electronic states: a PCM/TD-DFT study

Time dependent density functional theory and polarizable continuum model have been used to describe tetra-phenyl-porphyrin derivatives in different solvents and at different pH values. Our results show that last generation functionals are able to describe with good accuracy the photophysics of the title compounds, including different physical-chemical properties of excited electronic states. In particular, the strong modification of polarizabilities induced in some cases by electron excitation could explain a recent hypothesis about NLO characteristics of specific porphyrin adducts.

Growth, structural, thermal and optical studies on L‐glutamic acid hydrobromide – A new semiorganic NLO material

AbstractA new semiorganic crystal, L‐glutamic acid hydrobromide, C5H10NO4Br (GHB) has been grown from aqueous solution. The single crystal X‐ray analysis of the crystal showed that it belongs to the non‐centrosymmetric P212121 space group with protonated glutamic acid as cation and bromine as anion. The back‐bone conformations of the amino acid are in cis and trans form. The side‐chain conformations are observed to be in gauche I / trans / cis / trans forms. The characteristic ‘head‐to‐tail’ hydrogen bonding interaction is observed through a chain C(5) motif. Further, the crystal structure is stabilized by an intricate three‐dimensional hydrogen bonding network. TGA/DTA showed that the grown crystals are thermally stable upto 219 °C without any phase transition. The functional groups responsible for the various modes of vibrations were identified by using FTIR spectroscopy. UV‐Vis‐NIR spectra showed that the crystals have excellent transparency in the visible and infrared regions. The second harmonic generation (SHG) conversion efficiency was investigated to explore the NLO characteristics of the material. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Growth and characterization of Lithium hydrogen oxalate monohydrate, a new semiorganic NLO material

Single crystals of the semiorganic NLO material, lithium hydrogen oxalate monohydrate was grown and characterized by using single crystal X-ray diffraction. Spectroscopic, thermal and optical studies were carried out. These studies show that the crystals are thermally stable up to 100 °C, transparent for the fundamental and second harmonic generation of Nd:YAG (λ=1064 nm) laser. Second harmonic generation (SHG) conversion efficiency was investigated to explore the NLO characteristics of this material and it was found that the efficiency is about 91% of that of the standard KDP crystals. Laser damage threshold study was also carried out.