Evaluation Of Nonlinear Optical Properties Research Articles

Nonlinear optical and spectroscopic properties, thermal analysis, and hemolytic capacity evaluation of quinoline-1,3-benzodioxole chalcone.

This article describes the synthesis, characterization (1H NMR, 13C NMR, FT-IR, HRMS and XRD), UV-Vis absorption and fluorescence spectra, theoretical analysis, evaluation of nonlinear optical properties (NLO), thermal analysis and determination of the hemolytic capacity of the compound (E)-N-(4-(3-(benzo[d][1,3]dioxol-5-yl)acryloyl)phenyl)quinoline-3-carboxamide (5). Radiological findings showed that compound 5 crystallized in space group Pca21. Furthermore, theoretical DFT studies performed with the B3LYP and M062X functionals showed good agreement with the experimental results and provided valuable information on the molecular and electronic structure, reactivity, polarizability, and kinematic stability of the compound. Besides, compound 5 did not show any hemolytic effect on human erythrocytes and exhibited strong NLO properties. The TG and DTA thermograms of quinoline-chalcone (5) revealed a multi-step thermal decomposition process with a total mass loss of 83.2%, including water content loss. The DTA curves exhibited endothermic peaks corresponding to decomposition steps, melting point, and thermochemical transition. Additionally, exothermic peaks in the DTA thermograms align with significant mass loss, confirming the compound's melting point and water content, as validated by X-ray diffraction analysis. These results contribute to the advancement of research on compounds with NLO properties and offer a promising avenue for the development of substances potentially applicable to optical devices in the biomedical field.

Evaluation of nonlinear optical properties from molecular descriptors of benzimidazole metal complexes by principal component analysis

In the present work, semiempirical quantum chemical method (PM6) has been used for the simulation of molecular descriptors of first row transition metal ions incorporated benzimidazole metal complexes. Metal complexes with and without substituents are considered for the analysis. In both the cases, molecules show distinct properties with respect to the molecular descriptors. Since the dimension of the data set is large, principal component analysis has been used and the obtained principal components, PCA1 and PCA2, are linearly regressed with hyperpolarizability values. The obtained results indicate that molecular energy plays a dominant role in the nonlinear optical properties of benzimidazole metal complexes. Further, it is observed that the bond angle, global hardness and heat of formation of the molecules have considerable impact on the hyperpolarizability values.

Synthesis of symmetric ionic liquids and their evaluation of nonlinear optical properties

The synthesis, functionalization and anion-exchange of symmetric ionic liquids (SILs) and their nonlinear optical studies are reported. Imidazolium cation was obtained in 75–99% of yield by condensation reaction (Debus-Radziszewski) using different amine derivatives and employing inorganic and organic acid as catalyst. The nonlinear optical properties were evaluated by Z scan technique, at 514 nm of Ar laser, where the symmetric ionic liquid showed a nonlinear optical effect. The values of n2 are of the order ~10−8 cm2/W, while β value is 10−5 cm/W. The nonlinear refractive index increases due to the high concentration, symmetric structures and non-aliphatic chains. On the other hand, the coefficient of nonlinear absorption increases at low concentrations with symmetric structures and aliphatic chains.

Molecular origins of nonlinear optical activity in zinc tris(thiourea)sulfate revealed by high-resolution x-ray diffraction data andab initiocalculations

Structure-property relationships are established in the nonlinear optical (NLO) material, zinc tris(thiourea)sulfate (ZTS), via an experimental charge-density study, x-ray constrained wave-function refinement, and quantum-mechanical calculations. The molecular charge-transfer characteristics of ZTS, that are important for NLO activity, are topologically analyzed via a multipolar refinement of high-resolution x-ray diffraction data, which is supported by neutron diffraction measurements. The extent to which each chemical bond is ionic or covalent in nature is categorized by Laplacian-based bonding classifiers of the electron density; these include bond ellipticities, energy densities, and the local source function. Correspondingly, the NLO origins of ZTS are judged to best resemble those of organic NLO materials. The molecular dipole moment, ${\mathbit{\ensuremath{\mu}}}_{\mathbf{i}}$, and (hyper)polarizability coefficients, ${\mathbit{\ensuremath{\alpha}}}_{\mathbf{ij}}$ and ${\mathbit{\ensuremath{\beta}}}_{\mathbf{ijk}}$, are calculated from the experimental diffraction data using the x-ray constrained wave-function method. Complementary gas-phase ab initio quantum-mechanical calculations of ${\mathbit{\ensuremath{\mu}}}_{\mathbf{i}}$, ${\mathbit{\ensuremath{\alpha}}}_{\mathbf{ij}}$, and ${\mathbit{\ensuremath{\beta}}}_{\mathbf{ijk}}$ offer a supporting comparison. When taken alone, the experimental charge-density analysis does not fare well in deriving ${\mathbit{\ensuremath{\mu}}}_{\mathbf{i}}$, ${\mathbit{\ensuremath{\alpha}}}_{\mathbf{ij}}$, or ${\mathbit{\ensuremath{\beta}}}_{\mathbf{ijk}}$, which is not entirely surprising given that the associated calculations are only generally valid for organic molecules. However, by refining the x-ray data within the constrained wave-function method, the evaluations of ${\mathbit{\ensuremath{\mu}}}_{\mathbf{i}}$, ${\mathbit{\ensuremath{\alpha}}}_{\mathbf{ij}}$, and ${\mathbit{\ensuremath{\beta}}}_{\mathbf{ijk}}$ are shown to agree very well with those from ab initio calculations and show remarkable normalization to experimental refractive index measurements. The small differences observed between ab initio and x-ray constrained wave-function refinement results can be related directly to gas- versus solid-state phase differences. ${\mathbit{\ensuremath{\mu}}}_{\mathbf{i}}$ is found to be 28.3 Debye (gas phase) and 29.7 Debye (solid state) while ${\mathbit{\ensuremath{\beta}}}_{\mathbf{ijk}}$ coefficients are not only significant but are also markedly three dimensional in form. Accordingly, substantial octupolar as well as dipolar NLO contributions in ZTS are indicated, which challenges the traditional focus on dipolar NLO molecules. This evaluation of NLO properties and their relation to the molecular structure offers several ways by which ZTS may be more widely functionalized as a NLO material. More generally, this case study on ZTS demonstrates how experimental and computational techniques can be combined to understand NLO structure-property relationships, an important tool for the quantum-tailored molecular design of next-generation metalorganic NLO materials.

Synthesis of organometallic Ru(II) and Fe(II) complexes containing fused rings hemi-helical ligands as chromophores. Evaluation of non-linear optical properties by HRS

A new family of three-legged piano stool structured organometallic compounds containing the fragment η 5-cyclopentadienyl-ruthenium(II)/iron(II) has been synthesized to evaluate the existence of electronic metal to ligand charge transfer upon coordination of the novel benzodithiophene ligands ( BDT), benzo[1,2- b;4,3- b′]dithiophen-2-carbonitrile ( L1) and benzo[1,2- b;4,3- b′]dithiophen-2′nitro-2-carbonitrile ( L2). All the compounds were characterized by 1H, 13C, 31P NMR, IR and UV–Vis. spectroscopies and their electrochemistry studied by cyclic voltammetry. The X-ray structures of [Ru(η 5-C 5H 5)(PPh 3) 2(NCC 10H 5S 2)][PF 6] ( 1Ru), [Ru(η 5-C 5H 5)(PPh 3) 2(NCC 10H 5S 2)][CF 3SO 3] ( 1′ Ru), [Ru(η 5-C 5H 5)(DPPE)(NCC 10H 5S 2)][PF 6] 2Ru and [Fe(η 5-C 5H 5)(DPPE)(NCC 10H 5S 2)][PF 6] ( 2Fe) were determined by X-ray diffraction showing centric crystallization on groups P 1 ¯ and P2 1/ n, respectively. Quadratic hyperpolarizabilities ( β) of some of the complexes ( 2Fe, 2Ru and 3Fe) have been determined by hyper-Rayleigh scattering (HRS) measurements at a fundamental wavelength of 1500 nm, to minimize the probability of fluorescence due to two-photon absorption and to reduce the effect of resonance enhancement, in order to estimate static β values.

Hydrogen-bond effects on the electronic absorption spectrum and evaluation of nonlinear optical properties of an aminobenzodifuranone derivative that exhibits the largest positive solvatochromism

In this work, for the first time, a theoretical approach to describing the influence of hydrogen-bond formation on the electronic absorption spectrum and nonlinear optical properties of an aminobenzodifuranone derivative (ABF) that exhibits the largest positive solvatochromic shift compared to other known chromophores is given. The solvent effect was included via the supermolecule (SM) method. The calculations were performed for a strong low-lying (pi-->pi*) transition based on the configuration interaction singles (CIS) and time-dependent DFT (TDDFT) methods. The first-order hyperpolarizabilities (beta) were computed using the finite-field (FF) technique combined with the Hartree-Fock (HF) theory. Reasonable agreement between theory and experiment was obtained for the solvatochromic shifts of the ABF molecule. Moreover, it was found that H-bond formation strongly influences the NLO response of the systems investigated. [Figure: see text]. The interaction difference-density maps of the systems studied: a II--complex ABF with NFTB; b III--complex ABF with HMPA. The red color designates an increase of the electron density caused by the intermolecular interactions, whereas blue indicates a corresponding decrease of the electron density. The isodensity contours were plotted for +/-0.01 electron/bohr3 (DFT/B3LYP/6-31G(d,p)).

Synthesis, characterization and evaluation of nonlinear optical properties of chiral hydrobenzoin monomers

Four new monomers have been synthesized by condensation of the chiral pure reagents (R,R)-(+)-1,2-diphenyl-1,2-ethanediol and (S,S)-(–)-1,2-diphenyl-1,2-ethanediol ((R,R)-(+)-hydrobenzoin and (S,S)-(–)-hydrobenzoin, respectively) with methacryloyl chloride with the purpose of preparing structures that exhibit second harmonic generation of laser light and to polymerize them by free radical polymerization. The monomers (R,R)-(+)-1,2-diphenyl(2-methacryloyloxy)ethanol, (S,S)-(–)-1,2-diphenyl(2-methacryloyloxy)ethanol, (R,R)-(+)-1,2-diphenyl(1,2-dimethacryloyloxy)ethane and (S,S)-(–)-1,2-diphenyl(1,2-dimethacryloyloxy)-ethane were obtained and characterized by melting point measurements, infrared spectroscopy, nuclear magnetic resonance spectroscopy, gas chromatography with mass spectroscopy and polarimetry. The optical properties evaluation was made following the Kurtz and Perry modified procedure in powder form and using a Nd:YAG laser as pulse light source (≈ 0.466 mJ/mm2) at 1064 nm. The second harmonic generated light (532 nm) from each compound was compared with the calibration spectrum of a chiral compound (saccharose or sucrose, know as sugar) used as a standard. The second harmonic generation values measured showed that R,R (+)-1,2-diphenyl(2-methacryloyloxy)ethanol and (S,S)-(–)-1,2-diphenyl(2-methacryloyloxy)ethanol enantiomers had better efficiency of second harmonic generation than (R,R)-(+)-1,2-diphenyl(1,2dimethacryloyloxy)ethane and (S,S)-(–)-1,2-diphenyl(1,2-dimethacryloyloxy)ethane under the same conditions. In other words, the monoacylation products worked much better than the diacylation products or the hydrobenzoin enantiomers themselves from the SHG behavior point of view.

Chiral polyesters with azobenzene moieties in the main chain, synthesis and evaluation of nonlinear optical properties

The synthesis, characterization and evaluation of nonlinear optical properties of a new series of chiral copolyesters containing push-pull electronic azobenzene mesogenic groups in the main chain are reported. The copolyesters showed liquid crystalline behaviour with high glass transition temperatures (∼200 °C), stable liquid crystalline mesophases (up to 360 °C) and high second harmonic generation (SHG) efficiency. The second order nonlinear susceptibility values were measured as a function of the percentage of the chiral building unit and the temporal stability was found to be significant over a long duration of time.