S. AlFaify

An investigation on the key features of a D–π–A type novel chalcone derivative for opto-electronic applications

The current study is focused on the donor–bridge–acceptor (D–π–A) type of novel organic charge transport and non-linear optical material, 1-(4-bromophenyl)-3-(2,4,5-trimethoxyphenyl) prop-2-en-1-one (2,4,5-TMBC) to spotlight its various important properties through experimental and quantum chemical approaches. The compound 2,4,5-TMBC was synthesized via a Claisen–Schmidt condensation reaction and its single crystal was grown by a slow evaporation solution growth technique. FT-IR and FT-Raman spectra of 2,4,5-TMBC were obtained and investigated. The molecular geometry of 2,4,5-TMBC was optimized by HF, B3LYP, CAM-B3LYP, wb97xd and LC-BLYP methods using the 6-31G* basis set. The calculated geometrical parameters and vibrational spectra are in good agreement with the experimental results. Time dependent density functional theory (TD-DFT) has been applied to investigate the optical properties of the title compound. The absorption wavelength calculated at the TD-B3LYP/6-31G* level of theory in the gas phase was in good agreement with the experimental value (∼400 nm) when compared with other methods. The HOMO–LUMO energy gap was calculated at all the applied levels of theory. The total dipole moment, polarizability, anisotropy of polarizability and static first and total hyperpolarizability values of 2,4,5-TMBC were calculated at different levels of theory. The dipole moment and first hyperpolarizability values are found to be many folds (2 and 56 times calculated at B3LYP) higher than urea. It is also expected that 2,4,5-TMBC would be electron transport material due to its smaller electron reorganization energy value. The study of non-linear optical (NLO) properties shows that 2,4,5-TMBC would be an outstanding candidate for NLO device applications.

A dual approach to study the electro-optical properties of a noncentrosymmetric L-asparagine monohydrate.

In this work we reports the experimental and theoretical investigation on an organic noncentrosymmetric monohydrated L-asparagine (LAM) molecule. LAM single crystals were grown in specially designed beaker for the first time. Structural confirmation was done by identifying the vibrational modes using IR and FT-Raman spectroscopic studies. The ultra violet-visible-near infrared absorbance, diffuse reflectance spectra were recorded in the spectral range 190-2500 nm. The optical transparency was calculated and found to be ∼80%. Its optical band gap was calculated found to be ∼5.100 eV. Density functional theory (DFT) was employed to optimize the molecular geometry of LAM using B3LYP/6-31G(∗) basis set of theory. The HOMO-LUMO energy gap of 6.047 eV and transition energy of 176 nm (f0=0.024) have been found in semi-quantitative agreement with our experimental results. The dipole moment, polarizability and first hyperpolarizability were calculated at the same level of theory. The obtained results reveals that the titled compound can be a decent contender for nonlinear applications.

Experimental and density functional theory (DFT): A dual approach to study the various important properties of monohydrated l-proline cadmium chloride for nonlinear optical applications

In the current work we have applied the experimental and quantum chemical techniques to study the electro-optical and nonlinear optical properties of l-proline cadmium chloride monohydrate (LPCCM). Synthesis and good quality single crystals of LPCCM were grown (size=20mm×12mm×10mm). Crystal structure was confirmed by powder X-ray diffraction study. The calculated FT-IR and FT-Raman frequencies were analyzed. Detailed optical studies were carried out and various optical parameters are calculated. Using density functional theory, molecular geometry of LPCCM was optimized within framework of B3LYP/6-31G(∗). The calculated HOMO-LUMO energy gap of 5.484eV and transition energy of 5.565eV has been found in semi-quantitative agreement with experimental results. The value of dipole moment and first hyperpolarizability of LPCCM are found to be 2 and 6 times respectively, higher than that of urea. The obtained results reveal that the titled compound is a good candidate for nonlinear applications having an excellent transparency trade-off value.

Tailoring the structural, morphological, optical and dielectric properties of lead iodide through Nd 3+ doping

Hexagonal single crystal nanosheets of Nd3+ doped PbI2 were effortlessly synthesized via microwave-assisted technique under a power of 700 W and in a duration of 15 minutes with a homogeneous morphology. X-ray diffraction, energy dispersive X-ray spectroscope, scanning electron microscope, FT-Raman, UV-Visible, photoluminescence and dielectric measurement were employed to study the product. High purity, single phase and presence of Nd3+ doping was confirmed. SEM study confirm the formation of nanorods and single crystal nanosheets of very few nanometers in size. Robust vibrational analysis has been carried out and the observed bands are assigned to the vibration modes of E21, A11, A12, 2E21 and 2E11, respectively. These bands are red-shifted when compare to the corresponding bulk values which indicate relaxed nanostructure formation and occurrence of confinement effect. The thickness of the synthesized single crystal nanosheets are found to be in the range of ~20 to 30 nm. The energy band gap was calculated and found to be 3.35, 3.34, 3.42 and 3.39 eV for pure, 1, 3 and 5% Nd3+ doped lead iodide, respectively. The clear blue luminescence has been observed at 440 nm and 466 nm when excited at 250 nm and 280 nm respectively. Dielectric and ac electrical conductivity was also measured and discussed.

How does hybrid bridging core modification enhance the nonlinear optical properties in donor-π-acceptor configuration? A case study of dinitrophenol derivatives

This study spotlights the fundamental insights about the structure and static first hyperpolarizability (β) of a series of 2,4‐dinitrophenol derivatives (1–5), which are designed by novel bridging core modifications. The central bridging core modifications show noteworthy effects to modulate the optical and nonlinear optical properties in these derivatives. The derivative systems show significantly large amplitudes of first hyperpolarizability as compared to parent system 1, which are 4, 46, 66, and 90% larger for systems 2, 3, 4, and 5, respectively, at Moller–Plesset (MP2)/6‐31G* level of theory. The static first hyperpolarizability and frequency dependent coupled‐perturbed Kohn–Sham first hyperpolarizability are calculated by means of MP2 and density functional theory methods and compared with respective experimental values wherever possible. Using two‐level model with full‐set of parameters dependence of transition energy (ΔΕ), transition dipole moment (μ0) as well as change in dipole moment from ground to excited state (Δμ), the origin of increase in β amplitudes is traced from the change in dipole moment from ground to excited state. The causes of change in dipole moments are further discovered through sum of Mulliken atomic charges and intermolecular charge transfer spotted in frontier molecular orbitals analysis. Additionally, analysis of conformational isomers and UV‐Visible spectra has been also performed for all designed derivatives. Thus, our present investigation provides novel and explanatory insights on the chemical nature and origin of intrinsic nonlinear optical (NLO) properties of 2,4‐dinitrophenol derivatives.

First principal studies of spectroscopic (IR and Raman, UV-visible), molecular structure, linear and nonlinear optical properties of L-arginine p-nitrobenzoate monohydrate (LANB): A new non-centrosymmetric material.

In current work, the authors have been applied the density functional theory (DFT) using B3LYP and CAM-B3LYP exchange-correlation functional with 6-31G(∗) basis set on l-arginine p-nitrobenzoate monohydrate (LANB) molecule for the first time to optimize its geometry and study the spectroscopic, electronic structure, nonlinear optical properties. Vibrational modes were found in good agreement with experimental reports. The calculated UV spectra by B3LYP/6-31G(∗) and CAM-B3LYP/6-31G(∗) level of theory shows an electronic transition at ∼268 nm (4.63 eV) and 264 nm (4.70 eV) respectively. To explain the charge interaction taking place within the molecule highest occupied molecular orbital and lowest unoccupied molecular orbital were analyzed and their calculated energy gap was found to be 4.3eV with an oscillatory strength 0.3796 at B3LYP/6-31G(∗) level of theory. The dipole moment (μtot), average and anisotropy of polarizability (αtot, Δα) and static and total first hyperpolarizability (β0, βtot) values were calculated. The value of μtot and βtot are found to be 4.124D and 1.630 × 10(-30) esu and 4.127D and 1.133 × 10(-30) esu using B3LYP/6-31G(∗) and CAM-B3LYP/6-31G(∗) functional respectively. The value of βtot is >4 and >3 times higher than prototype urea molecule calculated at both level of theory, respectively. The molecular electrostatic potential (MEP), frontier molecular orbitals (FMOs), global reactivity descriptors and thermodynamic properties are also calculated and discussed. The properties of LANB calculated at B3LYP are in good correlation with experimental than the CAM-B3LYP level of theory. The obtained results show that LANB molecule can be treated as a good candidate for nonlinear optical devices.

Combined experimental and computational insights into the key features of L-alanine L-alaninium picrate monohydrate: growth, structural, electronic and nonlinear optical properties

In the current work, we spotlight the novel key features of L-alanine L-alaninium picrate monohydrate (LALAPM) using a dual approach comprised of experimental and computational techniques. Single crystals of LALAPM have been grown indigenously in three different ratios (1 : 1, 1 : 5, 2 : 1) through a slow cooling technique. The formations of different types of crystals were recorded during the growth process and found to vary significantly from each other. The grown crystals were subjected to single crystal powder X-ray diffraction analysis to confirm their respective crystal structures. Additionally, ultraviolet-visible-near infrared, diffuse reflectance measurements and optical parameter analysis were performed. The state-of-art computational techniques were used to get the ground state molecular geometry of LALAPM at the B3LYP/6-31G* level of theory. Different important electro-optical parameters (complementary to the experimental results) including IR, Raman, and UV-visible spectra have been calculated at the same level of theory. The polarizability and first hyperpolarizability (both static and dynamic) were calculated to see the potential applications of LALAPM in nonlinear optics. Furthermore, several novel molecular level insights have been obtained in the form of the total and partial density of states, the HOMO–LUMO gap and electrostatic potential maps etc. The obtained quantum chemical findings were compared with experimental results. The static and frequency dependent dynamic first hyperpolarizability values of the LALAPM molecule are found to be 8.06 × 10−30 and 10.24 × 10−30 esu that are about 37 times and 59 times larger than those of the prototype urea molecule, respectively, at the same B3LYP/6-31G* level of theory. The obtained results indicate that the titled compound contains good nonlinear optical properties and can be treated as a good contender for optoelectronic device fabrications.

Facile microwave-assisted synthesis of Te-doped hydroxyapatite nanorods and nanosheets and their characterizations for bone cement applications

In this work, the authors have fabricated the nanorods and nanosheets of pure and Te-doped HAp with different Te concentrations (0.04, 0.08, 0.16, 0.24wt%) by microwave-assisted technique at low temperature. The crystallite size, degree of crystallinity and lattice parameters are calculated. FE-SEM study confirms that the fabricated nanostructures are nanorods of diameter about 10nm in undoped and at low concentration of Te doping. However, at and higher concentration, it becomes nanosheets of about 5nm thickness. X-ray diffraction, FT-IR and FT-Raman studies shows that the prepared products are of HAp and Te has been successfully incorporated. From EDX the Ca/P molar ratio of the pure HAp is about 1.740, while this ratio for 0.04, 0.08, 0.16, 0.24 wt% Te doped is about 1.53, 1.678, 1.724, 1.792, respectively. Crystallite size was found to be increased with Te doping from 15nm to 62nm. The value of dielectric constant is found to be enhanced at higher concentrations of Te. The values of linear absorption coefficient were also determined and show that the prepared material with Te doping is more absorbable than pure and will be highly applicable in radiation detection applications. Furthermore, the antimicrobial potential of pure and Te doped HAp was examined against some Gram- negative and positive bacteria and fungi by agar disk diffusion method. The results demonstrated that the antimicrobial activity of Te doped HAp is stronger than that of pure HAp where it exhibited the highest activity against Bacillus subtilis>Candida albicans>Shigella dysenteriae.

Effect of organic ligands (L-Proline and L-Methionine) on growth, structural, vibrational, crystalline perfection, SHG efficiency, microscopic and optical properties of KDP single crystals.

The effect of L-Proline (LP) and L-Methionine (LM) doping on the various properties of KDP single crystals grown by slow evaporation solution technique has been investigated. The external morphology of the grown crystals was found to vary due to different dopants and doping concentrations. The change in powder X-ray diffraction intensity patterns due to doping shows the lattice distortion within resolution limit and confirms that there is no extra phase. Further, the same was confirmed by FT-Raman analysis. Infra red microscopic study also exhibits the effectiveness of doping in terms of varying surface morphology. Crystalline perfection of KDP crystals with LP and LM doping was examined by high-resolution X-ray diffraction. This shows very interesting features on the ability of accommodating the dopants in the crystalline matrix. Second harmonic generation efficiency was also found to be in similar fashion as of crystalline perfection. The optical transparency of doped crystals was tested.

Growth and optical studies of tris (thiourea) potassium barium sulphate crystal: a novel semiorganic NLO bimetallic crystal

Abstract A novel tris (thiourea) potassium barium sulphate (TTPBS) complex has been synthesized and the complex formation was confirmed by means of spectroscopic analysis. The TTPBS single crystal has been grown by most commercial slow solvent evaporation method. The single crystal X-ray diffraction technique has been employed to confirm the crystal structure and unit cell dimensions of TTPBS crystal. The functional groups of grown crystal have been identified by means of Fourier transform infrared analysis. The constituent elements of title crystal have been determined by means of EDS technique. In UV–visible studies the TTPBS crystal has been testified within 200–900 nm to examine the optical transparency and determine the optical band gap. The frequency conversion efficiency of TTPBS crystal has been assessed by means of Kurtz-Perry test. He–Ne laser assisted Z-scan technique has been employed to ascertain the third order nonlinear optical (TONLO) refraction and absorption effect in TTPBS crystal. The magnitude of TONLO refractive index (n 2), absorption coefficient (β) and susceptibility (χ3) of title crystal has been illustrated using the Z-scan data. The Nd:YAG laser facilitated surface damage threshold of TTPBS crystal has been determined and it is found to be in MW/cm2 range.