Design Of Nonlinear Optical Materials Research Articles

DFT, molecular docking and molecular dynamics simulations of 2-imino-4-oxo-1,3-thiazolidine hydrochloride and its activity against Bacillus pasteurii urease

Abstract According to reports, the bioactive thiourea derivative was prepared from the ethanol solutions of thiourea and chloro acetic acid in a 1:1 M ratio. DFT calculations of 2-Imino-4-oxo-1,3-thiazolidine hydrochloride (IOTH) were performed with the use of B3LYP and the 6-311+G(2d,p) basis set. Frontier molecular orbitals, mapped electrostatic potential (MEP) map, and nonlinear optical (NLO) properties of the IOTH were all assessed. The compound was tested for drug-likeness using Swiss ADME. Using B. pasteurii (PDB ID: 4UBP), calculations for molecular docking were then performed on the geometry-optimized structure. In order to determine the complex’s stability and the interactions between ligands and the receptor, the complex was subjected to molecular dynamics (MD) simulations. According to the results, the first hyperpolarizability value (β 0) was 7.459 × 10−24 esu. The large first hyper polarization rate theoretically supported its use in the design of NLO materials. The calculated HOMO–LUMO energy gap value of the IOTH was found to be 2.87 eV. The small HOMO–LUMO energy gap suggested that IOTH is a soft molecule with a high degree of chemical reactivity but poor kinetic stability. The molecular docking study showed that the best ligand pose energy for the IOTH was −101.35 kcal/mol whereas the standard drug (acetohydroxamic acid) was −64.29 kcal/mol. The results demonstrated that the ligand–receptor complex remained stable during the MD simulations due to high binding affinity to Bacillus pasteurii urease. The Lipinski Rule of Five was not violated in any way in the studied compound. This demonstrated that it is bioavailable. During clinical trials, the compound attrition rates would be lower, and the drug would have a better chance of being commercialized.

DFT analysis and electronic properties, and synthesis of tetra (9-phenyl-9H-xanthen-9-yl) oxy peripheral-substituted zinc phthalocyanine

The 4-((9-phenyl-9H-xanthene-9-yl) oxy) phthalonitrile compound was synthesized and characterized as starting material. Zinc phthalocyanine was obtained by reaction of 4-((9-phenyl-9H-xanthen-9-yl) oxy) phthalonitrile with Zn(CH3COO)2. Novel compounds were characterized using mass spectra, UV–Vis spectroscopy, 1H-NMR, 13C NMR, and infrared spectroscopy. The fluorescence, emission, excitation, and absorption spectra of the zinc phthalocyanine compound were studied in tetrahydrofuran (THF). The determination of these properties is very useful for photodynamic therapy applications. Also, zinc phthalocyanine (Zn-Pc) was optimized with the basic set of 6-311G and LanL2DZ of the Density functional theory (DFT). The energy band-gap HOMO–LUMO of the molecule was determined. Chemical indices were calculated using HOMO–LUMO energies. The electrophilic region and the nucleophilic region were defined from the molecular electrostatic potential (MESP) maps. Dipole moment components have been calculated and can be considered as potential candidates for the design of non-linear optical materials.

Giant enhancement of the nonlinear optical properties of [2.2]paracyclophanes by an donor-bridge-acceptor

Recently, the modulating the charge transfer of the donor-S-acceptor (DSA) has been proven as an appropriate method to increase the static first hyperpolarizability of the molecule. In this work, we employ the extended π-conjugated bridge to further explore the charge transfer effect on the nonlinear optical response, where (CHCH)nNH2 and (CHCH)nNO2 are served as an donor group and acceptor group, respectively. Electrostatic potentials on the molecular surface of all molecules indicate that charge transfer is found from donor group to acceptor group, which indicates that these molecules may be excellent nonlinear optical materials. The calculations proves that these molecules exhibit large first hyperpolarizability in the range of 3485−46199 au. Compared with short chain, long chain brings these molecules the large first hyperpolarizability, which are 146199 au for n = 4. Moreover, the ultraviolet-visible-infrared indicate that the molecule is transparent in the deep-ultraviolet, which may be regarded as a new candidate for deep ultraviolet nonlinear optical materials. The transition can give reasons for the change in the first hyperpolarizability of these molecules. We hope that this paper can provide new insights for the design of nonlinear optical materials.

Cyclometalated iridium(III) complex containing indolinyl-based phenanthroline ligand: Synthesis, structure and photophysical properties

A heteroleptic cationic Ir(III) complex [(X)2Ir(L)]+PF6− was designed and synthesized, where L = 2-(1,3,3-trimethylindolin-2-yl)oxazolo[4,5-f] [1,10]phenanthroline, X = 2-phenylpyridine (ppy). Its structural and photophysical properties have been systematically investigated via a series of spectroscopic methods. This complex exhibits ligand-localized 1π,π* transitions below 350 nm, broad and structureless metal-to-ligand/ligand-to-ligand charge transfer (1MLCT/1LLCT) transitions between 350 and 450 nm, and spin-forbidden 3MLCT/3LLCT/3π,π* transitions above 450 nm. Upon excitation at its absorption maximum, the complex exhibits orange phosphorescence in solution. In addition, this complex exhibits strong excited-state absorption in the visible spectral region, good anti-photobleaching and electrochemical stability. Reverse saturable absorption (RSA) of this complex was demonstrated at 532 nm using 4.1 ns laser pulses, which would be useful for a rational design of nonlinear optical materials.

Extended π-conjugated quinazolinone derivatives with enhanced third-order nonlinear optical response

A series of quinazolinone derivatives have been designed and synthesized based to the structure of donor-π-acceptor-π-donor (D-π-A-π-D). In order to obtain materials with good third-order nonlinear optical response that we have introduced some electron-donating groups such as triarylamine, cumene, and N,N-dimethylaniline into the 8- or 2,8- position of the quinazolinone. Compared with the parent QZ-1, the target compounds showed a significant red shift. Electrochemical data and theoretical calculation showed that the introduction of the donor group that extended the conjugation length of the molecule and reduced the HOMO/LOMO band gap which promoted the intramolecular charge transfer (ICT). Z-scan results demonstrated that as the electron-donating ability of the donor group increased, the synthetic materials exhibit stronger nonlinear optical response. Among them, QZB-1 incorporating with two triarylamine groups has a γ value of 34.616 × 10−32 esu, which is up to 38 times of the parent structure. The results of this study have guiding significance for the molecular design of nonlinear optical materials.

Enhanced nonlinear optical properties of porphyrin with an extended π-conjugated bridge

In this work, a series of molecules with an extended π-conjugated bridge have been theoretically designed based on porphyrin, where -(CH=CH)n- (n = 1–4, 8, 12) chain is served as an extended π-conjugated bridge. It is found that all molecules exhibit large energy gaps in the range of 3.484–4.151 eV for porphyrin-(CH=CH)n-NH2, and 3.624–4.250 for porphyrin-(CH=CH)n-NO2. The maximum absorption wavelengths of all molecules show a red shift trend with increasing -(CH=CH)n- length, which leads to small transition energy. It is observed that long chain brings these molecules the large first hyperpolarizability, which are 1.04 × 105 au for porphyrin-(CH=CH)12-NH2, 1.26×105 au for porphyrin-(CH=CH)12-NO2. Moreover, compared with -(CH=CH)n-NH2 with the same chain length, -(CH=CH)n-NO2 chain can achieve larger nonlinear optical response. It is hoped that the research in this paper can provide a new strategy for the experimental design of nonlinear optical materials.

Study of Photophysical Properties on Newly Synthesized Coumarin Derivatives.

Herein, we have studied the photophysical properties for three newly synthesized coumarin derivatives; 4-((2,6-dibromo-4-methylphenoxy)methyl)-2H-benzo[h]chromen-2-one (DMB), 4-((3,4-dihydro-6,7-dimethoxyisoquinolin-1-yl)methyl)-6-methyl-2H-chromen-2-one (DIM) and 4-((p-tolyloxy)methyl)-6-methoxy-2H-chromen-2-one (TMC). The absorption and emission spectra for above said molecules were recorded in different solvents at room temperature in order to calculate their ground and excited state dipole moments. The ground (μ g ) and excited state dipole (μ e ) moments of these coumarin derivatives were calculated using Lippert's, Bakshiev's and Kawski-Chamma-Viallet's equations by the solvatochromic shift method, which involves a variation of Stokes shift with the solvent dielectric constant and refractive index. Ground state dipole moments (μ g ) were also calculated from the Guggenheim method using the dielectric constant and refractive index of the solute molecule. The value of ground state dipole moment obtained from these two methods is well correlated. Further, it is notified that the excited state dipole moment is larger than the ground state dipole moment for all three solute molecules. It inferred that the excited state for above said molecules is more polar than the ground state. The present investigations may shine in the design of nonlinear optical materials. Graphical Abstract The photophysical properties for novel coumarin derivatives were studied in different solvents.Ground and excited state dipole moments were estimated by the solvatochromic shift method. The excited state dipole moment is greater than the ground state dipole moment in systems studied. The excited state is more polar than the ground state. The present investigation may be shine in the design of non linear optical materials.

Influence of Spiral Framework on Nonlinear Optical Materials

A series of spiral donor-π-acceptor frameworks (i.e. 2-2, 3-3, 4-4, and 5-5) based on 4-nitrophenyldiphenylamine with π-conjugated linear acenes (naphthalenes, anthracenes, tetracenes, and pentacenes) serving as the electron donor and nitro (NO2 ) groups serving as the electron acceptor were designed to investigate the relationships between the nonlinear optical (NLO) responses and the spirality in the frameworks. A parameter denoted as D was defined to describe the extent of the spiral framework. The D value reached its maximum if the number of NO2 groups was equal to the number of fused benzene rings contained in the linear acene. A longer 4-nitrophenyldiphenylamine chain led to a larger D value and, further, to a larger first hyperpolarizability. Different from traditional NLO materials with charge transfer occurring in the one-dimensional direction, charge transfer in 2-2, 3-3, 4-4, and 5-5 occur in three-dimensional directions due to the attractive spiral frameworks, and this is of great importance in the design of NLO materials. The origin of such an enhancement in the NLO properties of these spiral frameworks was explained with the aid of molecular orbital analysis.

Quantum chemical design of nonlinear optical materials by sp2-hybridized carbon nanomaterials: issues and opportunities

Nonlinear optical (NLO) materials are the smartest materials of the era, and have the ability to generate new electromagnetic fields with changed frequencies, phases, and other physical properties. Recently, many cutting edge research reports have been focused on NLO materials especially on those which are composed of sp2 hybridized carbon nanostructures. As the carbon nanostructures are composed of abundant π-electrons and have significant delocalization, these are potential candidates for modern NLO materials. Generally, sp2 hybridized carbon nanostructures can be divided into zero-dimensional fullerenes, one-dimensional nanotubes and two-dimensional graphene nanoribbons and quantum dots etc. These dimensionally different carbon nanomaterials are promising candidates for a wide range of applications in next-generation nanotechnologies. In present feature article, we first briefly explain a theoretical structure–NLO property relationship based on perturbation theory and then elucidate the crucial factors to control the NLO responses. We put together the different random investigations of sp2 hybridized carbon nanostructures for NLO application by highlighting the importance of their several structural designs to tune NLO amplitudes. Furthermore, we make a comparative and updated analysis of the NLO properties of dimensionally different sp2 hybridized carbon nanomaterials i.e. fullerenes, carbon nanotubes, and graphene nanoribbons and quantum dots. Finally, we make a brief discussion about different aspects and opportunities to use the sp2 hybridized carbon nanomaterials as high performance NLO materials of the future. This review is a focused perspective based on different updated quantum chemical investigations about fullerenes, nanotubes and graphene nanoribbons and quantum dots for their possible use in nonlinear optical applications.

First Hyperpolarizability Dispersion of the Octupolar Molecule Crystal Violet: Multiple Resonances and Vibrational and Solvation Effects

The first hyperpolarizability (β) dispersion curve is measured for the first time for an octupolar nonlinear optical (NLO) molecule (crystal violet, CV) and modeled theoretically, yielding an in-depth understanding of the electronic structure and vibronic and solvation effects on such octupolar conjugated systems. Tunable wavelength hyper-Rayleigh scattering (HRS) measurements were performed on this prototypical octupolar molecule in the broad fundamental wavelength range of 620-1580 nm, showing significant shortcomings of the commonly used β dispersion models. Three well-separated β resonances involving the lowest-energy state and several higher excited states are clearly observed, including a significant contribution from a nominally one-photon forbidden transition. The experimental results for second-harmonic wavelengths above 330 nm are successfully modeled by means of a vibronically coupled essential-state description for octupolar chromophores, developed by Terenziani et al. (J. Phys. Chem. B 2008, 112, 5079), which takes into account polar solvation effects. The relative intensities of the various resonances, including the one below 330 nm, are also quantified by quantum chemical calculations. Furthermore, interesting effects of inhomogeneous broadening due to polar solvation of the two-dimensional chromophore are recognized in both linear and nonlinear spectra, allowing us to quantitatively address the long-standing problem of the band shape of the linear absorption spectrum of CV. This clearly demonstrates that extensive wavelength-dependent HRS measurements, as presented in this work, are essential to the characterization and design of NLO materials and represent a powerful tool to gain valuable information on molecular excitations and environmental effects in general.

Ultrafast Optical Excitations In Supramolecular Metallacycles with Charge Transfer Properties

New organometallic materials such as two-dimensional metallacycles and three-dimensional metallacages are important for the development of novel optical, electronic, and energy related applications. In this article, the ultrafast dynamics of two different platinum-containing metallacycles have been investigated by femtosecond fluorescence upconversion and transient absorption. These measurements were carried out in an effort to probe the charge transfer dynamics and the rate of intersystem crossing in metallacycles of different geometries and dimensions. The processes of ultrafast intersystem crossing and charge transfer vary between the two different classes of metallacyclic systems studied. For rectangular anthracene-containing metallacycles, the electronic coupling between adjacent ligands was relatively weak, whereas for the triangular phenanthrene-containing structures, there was a clear interaction between the conjugated ligand and the metal complex center. The transient lifetimes increased with increasing conjugation in that case. The results show that differences in the dimensionality and structure of metallacycles result in different optical properties, which may be utilized in the design of nonlinear optical materials and potential new, longer-lived excited state materials for further electronic applications.

Conformational dependence of the first molecular hyperpolarizability in the computational design of nonlinear optical materials for optical switching

In certain cases for conjugated molecules, which can often be found in several conformations close in energy, hyperpolarizabilities of the rotamers differ by less than 20%, which is comparable to uncertainty in experimental data and this makes it possible to consider only one representative conformation in the process of computational design.

Rational Design of Nonlinear Optical Materials Based on 2D Coordination Networks

Zinc(II) and cadmium(II) coordination networks with m-pyridinecarboxylate bridging ligands, Zn(nicotinate)2, 1, Cd(nicotinate)2, 2, Cd{3-[2-(4-pyridyl)ethenyl]benzoate}2, 3, Zn4{3-[2-(4-pyridyl)ethenyl]benzoate}8·{3-[2-(4-pyridyl)ethenyl]benzoic acid}·(H2O), 4, Zn{4-[2-(3-pyridyl)ethenyl]benzoate}2·H2O, 5, and Zn{5-[2-(3-pyridyl)ethenyl]thiophene-2-carboxylate}2, 6, have been synthesized under hydro(solvo)thermal conditions. With the exception of 5, these compounds adopt 2D grid structures. The use of unsymmetrical bent m-pyridinecarboxylate ligands leads to the formation of intrinsically acentric 2D grids which provide an interesting structural motif for the rational synthesis of polar solids. Compounds 1 and 3−5 are non-centrosymmetric and show significant powder second harmonic generation efficiencies. Compound 2 adopts a centrosymmetric structure due to the presence of a μ2,η3-carboxylate bridge, while compound 6 adopts a centrosymmetric structure due to the presence of 2-fold interpenetration. The present work illustrates the potential of rational synthesis of nonlinear-optical-active acentric solids by exploiting the propensity of the formation of 2D coordination networks based on bent linking groups. Crystal data for 1: tetragonal space group P43212, a = 7.709(1) Å, b = 7.709(1) Å, c = 20.327 Å, and Z = 8. Crystal data for 2: monoclinic space group P21/n, a = 10.055(1) Å, b = 10.219(1) Å, c = 12.733(1) Å, β = 105.169(2)o, and Z = 4. Crystal data for 3: orthorhombic space group Fdd2, a = 20.622(1) Å, b = 36.426(1) Å, c = 6.241(1) Å, and Z = 8. Crystal data for 4: monoclinic space group Cc, a = 21.875(2) Å, b = 15.158(1) Å, c = 32.863(2) Å, β = 102.997(1), and Z = 4. Crystal data for 5: orthorhombic space group P21212, a = 7.625(1) Å, b = 25.430(2) Å, c = 5.863(1) Å, and Z = 4. Crystal data for 6: orthorhombic space group Pcca, a = 17.150(2) Å, b = 9.966(1) Å, c = 12.108(2) Å, and Z = 8.

Static and frequency dependent polarizabilities and hyperpolarizabilities of H2Sn

The structure–polarization relationship was investigated in a series of polysulfanes, H2Sn. The reported results demonstrate that the forms of change of the polarizability components, αii, and the second hyperpolarizability components, γiiii, as well as the average values α and γ, respectively, of H2Sn with n are similar. This shows that polarizability components can be easily used to determine corresponding hyperpolarizability data. A remarkable change of the hyperpolarizabilities with the molecular geometry of H2Sn was found. This result can be used for the design of nonlinear optical materials with optimum properties. The present study uses the flexible σ bonded H2Sn and is complementary to the works that considered the effect of conformational changes of π-conjugated systems on their hyperpolarizabities. The present computations were performed using the semiempirical approaches MNDO and MNDO/d, as well as ab initio methods with STO-3G, extended with polarization and diffuse functions, and [3s2p/7s5p2d] sets for H2Sn. At the ab initio level, the electronic and the vibrational contributions to polarizabilities and hyperpolarizabilities were both computed for several members of H2Sn. The frequency dependence of the above contributions and the static limit were discussed. Electron correlation was taken into account for several test cases using MP2 theory. The selected methods and the variety of the approximations on which they rely allow the systematic consideration of the effect of changes of the geometry of H2Sn on their polarizabilities and second hyperpolarizabilities. © 1998 John Wiley & Sons, Inc. J Comput Chem 19: 1698–1715, 1998

Nonlinearity Enhancement by Solid-State Proton Transfer: A New Strategy for the Design of Nonlinear Optical Materials

Theoretical considerations of the molecular hyperpolarizabilities (β) of donor−acceptor substituted aromatic molecules show that the transfer of a proton from the electron-donor group of an acid to the electron acceptor group of a base could increase β for both resulting ionic species relative to the corresponding neutral molecules. To take advantage of this, the cocrystallization of 4-nitrophenol with various organic bases was studied. Cocrystallization of 4-nitrophenol with 4-(dimethylamino)pyridine gives yellow crystals that display a strong second harmonic signal by the Kurtz and Perry powder test. The material crystallizes in the orthorhombic space group P212121 and is composed of 4-(dimethylamino)pyridinium 4-nitrophenolate 4-nitrophenol (DMAPNP2). Theoretical calculations of the hyperpolarizabilities predict that the values of β are greater for the 4-(dimethylamino)pyridinium and 4-nitrophenolate ions than for the corresponding neutral molecules. A second noncentrosymmetric material has been grown ...

Many-electron hyperpolarizability density analysis: Application to the dissociation processof one-dimensionalH2s

A method for density analysis of static polarizabilities (\ensuremath{\alpha}) and second hyperpolarizabilities (\ensuremath{\gamma}) on the basis of the finite-field (FF) many-electron wave packets (MEWP) method is developed and applied to evaluation of the longitudinal \ensuremath{\alpha} and \ensuremath{\gamma} in the dissociation process for a one-dimensional ${\mathrm{H}}_{2}$ model. Remarkable increases in \ensuremath{\alpha} and \ensuremath{\gamma} are observed in the intermediate dissociation region. The internuclear distance where the \ensuremath{\gamma} is maximized is also found to be larger than that where the \ensuremath{\alpha} is maximized. In order to elucidate the characteristics of \ensuremath{\alpha} and \ensuremath{\gamma} in the dissociation process, we extract their classical pictures describing displacements of two-electron configurations by using (hyper)polarizability densities on the two-electron coordinate plane. It is suggested from these classical pictures that the polarization in the ionic structure contributes primarily to the enhancement of (hyper)polarizability in the intermediate dissociation region, while the polarization in the diradical structure causes the decrease of the (hyper)polarizability at a large internuclear distance. This implies that the experimental search for species with chemical bonds in the intermediate correlation regime is important and interesting in relation to the molecular design of nonlinear optical materials.

Guanidinium Para-Substituted Benzenesulfonates: Competitive Hydrogen Bonding in Layered Structures and the Design of Nonlinear Optical Materials

Guanidinium Para-Substituted Benzenesulfonates: Competitive Hydrogen Bonding in Layered Structures and the Design of Nonlinear Optical Materials

Chemists are crucial to progress in design of nonlinear optical materials

Chemists are crucial to progress in design of nonlinear optical materials

Chemists are crucial to progress in design of nonlinear optical materials

No abstract available.

Calculations of dipole moments, optical spectra, and second-order hyperpolarizability coefficients of some mono- and disubstituted stilbene models for the design of nonlinear optical materials

Conclusion In this study we have gained additional insight into the mechanism of Hz production from water mediated by colloidal metal catalysts. The differing rates of decay of MV+ and of the conductiity signal observed in this investigation show that charging of the Ptc by electrons is followed by a slower uptake of protons and that the reducing species loading the Ptc above pH 7 cannot be assigned a simple formula like H-, although once equilibrium is established on the catalyst, the ratios of protons to electrons do not differ greatly from 0.5 predicted by this formula. Although both initial [MV'] and [Ptc] strongly affect the fractional decay of MV' , the concentration of MV2+ has little effect. An equilibrium with a Ptc surface saturated with adsorbed MV2+ is suggested. Slow changes in optical absorption and conductivity were found which can be attributed to equilibration of the Ptc with hydrogen (produced with G = 1.0). The ratio of protons to electrons loading the Pt was found for this process to be similar to that in the case of reduction of the Ptc by MV+. The results described above therefore allow us to obtain a more complete understanding of the role played by colloidal metal catalysts in water reduction to hydrogen and have demonstrated the value of using the pulse radiolysis technique together with optical and conductivity detection methods in enabling us to probe such reaction systems.