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Ab-initio and DFT methodologies for computing hyperpolarizabilities and susceptibilities of highly conjugated organic compounds for nonlinear optical applications
(ELSEVIER SCIENCE BV, 2016) Karakas, A.; Karakaya, M.; Ceylan, Y.; El Kouari, Y.; Taboukhat, S.; Boughaleb, Y.; Sofiani, Z.
In this talk, after a short introduction on the methodologies used for computing dipole polarizability (alpha), second and third-order hyperpolarizability and susceptibility; the results of theoretical studies performed on density functional theory (DFT) and ab-initio quantum mechanical calculations of nonlinear optical (NLO) properties for a few selected organic compounds and polymers will be explained. The electric dipole moments (mu) and dispersion-free first hyperpolarizabilities (beta) for a family of azo-azulenes and a styrylquinolinium dye have been determined by DFT at B3LYP level. To reveal the frequency dependent NLO behavior, the dynamic a, second hyperpolarizabilities (gamma), second (chi((2))) and third-order (chi((3))) susceptibilites have been evaluated using time-dependent HartreeFock (TDHF) procedure. To provide an insight into the third-order NLO phenomena of a series of pyrrolo-tetrathiafulvalene-based molecules and pushpull azobenzene polymers, two-photon absorption (TPA) characterizations have been also investigated by means of TDHF. All computed results of the examined compounds are compared with their previous experimental findings and the measured data for similar structures in the literature. The one-photon absorption (OPA) characterizations of the title molecules have been theoretically obtained by configuration interaction (CI) method. The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps have been revealed by DFT at B3LYP level for azo-azulenes, styrylquinolinium dye, push-pull azobenzene polymers and by parametrization method 6 (PM6) for pyrrolo-tetrathiafulvalene-based molecules. (C) 2016 Elsevier B.V. All rights reserved.
Comparison between Quantum Mechanical Computations of NLO Properties and Experimental Data in Selected Functionalized Azo-Dyes
(IEEE, 2012) Sahraoui, B.; Karakas, A.; Hajjaji, A.; El Kouari, Y.; Migalska-Zalas, A.
Nonlinear optical (NLO) materials have been extensively studied for many years. The search of new materials with NLO properties is an important research field. Significant interest still exists in the design and development of materials exhibiting large second and third-order NLO response because of the potential application in optoelectronics devices [1-2]. In this talk, comparison between quantum mechanical computations of NLO properties and experimental data in selected azo-dyes will be done. Particularly we will focus on correlation between macroscopic level and microscipic one. To reveal the microscopic second-order NLO properties of a family of azo-azulenes, the electric dipole moments (mu) and static first hyperpolarizabilities (beta) have been evaluated by using density functional theory (DFT) quantum mechanical calculations at B3LYP/6-311+G (d, p) level. The calculation results with non-zero values on first hyperpolarizabilities indicate that the title molecules might possess microscopic second-order NLO phenomena. The maximum one-photon absorption (OPA) wavelengths obtained by theoretical computations using the configuration interaction (CI) method are located in the visible region, supporting the pi -> pi* transitions. We have also calculated the dynamic second (chi((2))) and third-order chi((3)) susceptibilities using the time-dependent Hartree-Fock (TDHF) method.
Computational studies on linear, second and third-order nonlinear optical properties of novel styrylquinolinium dyes
(ELSEVIER, 2016) Karakas, A.; Karakaya, M.; Taser, M.; Ceylan, Y.; Gozutok, A.; Arof, A. K.; El Kouari, Y.
The electric dipole moments (mu), static dipole polarizabilities (alpha) and first hyperpolarizabilities (beta) of styrylquinolinium dyes, D8 and D21, have been computed by density functional theory (DFT). The one photon absorption (OPA) characterizations have been investigated using UV-vis spectroscopy and further interpreted using computational chemistry. The time-dependent Hartree-Fock (TDHF) method has been used to describe the dynamic dipole polarizabilities, dynamic second-order and also static and dynamic third-order nonlinear optical (NLO) properties. D8-D21 have rather high beta and second hyperpolarizabilities (gamma). The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps for D8-D21 have been evaluated by DFT. (C) 2016 Elsevier B.V. All rights reserved.
Determination of Dipole Polarizabilities and Second Hyperpolarizabilities in Alkynyl-Ruthenium Complexes Using Quantum-Chemical Calculations
(IEEE, 2013) Karakas, A.; Dag, T.; Migalska-Zalas, A.; Fillaut, Jean-Luc; Sahraoui, B.
To investigate dispersion-free third-order nonlinear optical (NLO) behaviour of a series of ruthenium complexes, static dipole polarizabilities (alpha) and second hyperpolarizabilities (gamma) have been determined by time-dependent Hartree-Fock (TDHF) method. To provide an insight into the frequency-dependent third-order NLO phenomena of the title compounds, the dynamic dipole polarizabilities and second hyperpolarizabilities using TDHF procedure have been also computed at the wavelengths used in third-harmonic generation (THG) measurements. According to the computation results, the examined molecules exhibit second hyperpolarizabilities with non-zero values, implying microscopic third-order NLO behaviour. To compare our theoretical results on third-order NLO manner with corresponding experimental data, we also give the calculation results of the dynamic third-order susceptibilities (X-(3)) for the studied complexes.
Diagnostic and control of linear and nonlinear optical effects in selected self-assembled metallophthalocyanine chlorides nanostructures
(ELSEVIER SCI LTD, 2018) Zawadzka, A.; Waszkowska, K.; Karakas, A.; Plociennik, P.; Korcala, A.; Wisniewski, K.; Karakaya, M.
In this paper we described a new self-assembly phenomenon of the metallophthalocyanine chlorides nanostructures and its influence on the linear optical properties as well as the Second Harmonic Generation process. The self-assembly phenomenon were achieved through an annealing process carried out immediately after the deposition process. The studied nanostructures were subjected to the annealing process for 24 h and the temperature of the process was equal to 525 K. We discussed experimental results and theoretical calculations of structural, linear and nonolinear optical properties for aluminum and gallium phthalocyanine chlorides. The linear and second-order nonlinear optical properties for these compounds were investigated at microscopic and macroscopic levels. The electric dipole moments and dispersion-free first hyperpolarizabilities were determined by quantum chemical calculations based on Density Functional Theory. Ab-initio quantum mechanical calculations (time-dependent Hartree-Fock method) for the studied metallophthalocyanine chlorides were carried out to compute the frequency-dependent first hyperpolarizabilities and second-order susceptibilities at the wavelengths used in SHG measurements. Our results shed light on the linear and nonlinear optical properties of the nanostructures. The results showed that second harmonic signal is strong and polarized, and this polarizing effect was achieved by controlling the arrangement of the molecules inside the formed nanostructures. Our results also reveal potential application of the nanostructures not only for nonlinear optics but also for thermal sensor devices.
The Investigation of Third-Order Hyperpolarizabilities and Susceptibilities of Push-Pull Azobenzene Polymers
(IEEE, 2013) Karakas, A.; EL Ouazzani, H.; Kirkan, N.; Krupka, O.; Smokal, V.; Migalska-Zalas, A.; Sahraoui, B.
To estimate the potential for third-order nonlinear optical (NLO) properties of the title azobenzene polymers, the one-photon absorption (OPA) and two-photon absorption (TPA) characterizations have been determined by configuration interaction (CI) and time-dependent Hartree-Fock (TDHF) methods, respectively. The nonlinear absorption parameters (beta) and third-order susceptibilities (chi((3))) have been measured by performing the Z-scan measurements. According to the ab-initio computation results, the investigated compounds exhibit averaged (isotropic) second hyperpolarizabilities () with non-zero values, implying microscopic third-order optical nonlinearity. Our computed results on TPA cross-sections (delta(omega)), third-order hyperpolarizability and susceptibility values are in accord with the experimental observations of the examined molecules.
One-photon Absorption Characterizations, Dipole Polarizabilities and Second Hyperpolarizabilities of Chlorophyll a and Crocin
(SCIENDO, 2018) Karakas, A.; Ceylan, Y.; Karakaya, M.; Taser, M.; Terlemez, B. B.; Eren, N.; El Kouari, Y.
The dispersion-free dipole polarizability (alpha) computations for chlorophyll a (1) and crocin (2) have been achieved by density functional theory (DFT) at B3LYP/ 6-31G(d) level. The measured one-photon absorption (OPA) wavelengths are quite consistence with the theoretically obtained values. Ab-initio quantum chemical calculations (time-dependent Hartree-Fock (TDHF)) have been implemented to reveal the static second hyperpolarizabilities (gamma) and dynamic dipole polarizabilities of the title molecules. The examined compounds display gamma with non-zero values, introducing their third-order nonlinear optical (NLO) phenomena. The first and second frontier molecular orbitals of the investigated molecules have been also derived from DFT.
Optical and structural characterization of thin films containing metallophthalocyanine chlorides
(ELSEVIER SCI LTD, 2015) Zawadzka, A.; Karakas, A.; Plociennik, P.; Szatkowski, J.; Lukasiak, Z.; Kapceoglu, A.; Ceylan, Y.
The structural and optical investigation of thin films containing aluminum and gallium phthalocyanine chlorides is presented. The films were fabricated by Physical Vapor Deposition technique onto quartz substrates and annealed after fabrication in an ambient atmosphere for 24 h at the temperature equal to 150 degrees C or 250 degrees C. The experimental results and theoretical calculation of the Third Harmonic Generation process are reported. The third order nonlinear optical properties are expected and can be more or less accurately predicted due to the assembly of the molecules and theoretical calculations of the frequency-dependent dipole polarizabilities, third hyperpolarizabilities, third order susceptibilities, frontier and second frontier molecular orbitals. These parameters were used to understand the relationship of optical properties with the molecular structures. We found that the annealing process causes formation of nanostructures and the value of the third order optical susceptibility makes these materials interesting for future nonlinear optical applications. (C) 2014 Elsevier Ltd. All rights reserved.
Quantum chemical calculations and experimental studies of third-order nonlinear optical properties of conjugated TTF-quinones
(ELSEVIER SCIENCE BV, 2013) Karakas, A.; Migalska-Zalas, A.; El Kouari, Y.; Gozutok, A.; Karakaya, M.; Touhtouh, S.
To investigate microscopic third-order nonlinear optical (NLO) behaviour of two tetrathiafulvalene (TTF) derivatives, TTF-diquinone triad (1) and TTF-monoquinone dyad (2), we have computed both dispersion-free and also dispersion of dipole polarizabilities (alpha) and third-order hyperpolarizabilities (gamma) at 532 nm wavelength using time-dependent Hartree-Fock (TDHF) method. The one-photon absorption (OPA) characterizations of the title molecules have been theoretically obtained by means of configuration interaction (CI) method with all doubly occupied molecular orbitals. We have also calculated the dynamic third-order susceptibilities (chi((3))) using the TDHF method. Our theoretical results on the maximum OPA wavelengths, third-order susceptibilities and corresponding microscopic NLO responses are in good agreement with the previous experimental observations of the examined TTF-based molecules. The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps for I and 2 have been evaluated by density functional theory (DFT) quantum mechanical calculations at B3LYP/6-31 G(d,p) level. (C) 2013 Elsevier B.V. All rights reserved.
Second and third-order nonlinear optical behavior of natural pigment: chlorophyll and crocin
(SPRINGER HEIDELBERG, 2017) Karakas, A.; Karakaya, M.; Taser, M.; Ceylan, Y.; Arof, A. K.; El Kouari, Y.; Sahraoui, B.
To provide an insight into the microscopic second and third-order nonlinear optical (NLO) behavior of chlorophyll a and crocin, we have computed the electric dipole moments (mu), dispersion-free first hyperpolarizabilities (beta), frequency-dependent first and second (gamma) hyperpolarizabilities at 1064 nm wavelength area using time-dependent Hartree-Fock (TDHF) method. According to ab-initio calculation results, the examined compounds exhibit first and second hyperpolarizabilities with non-zero values, implying second and third-order NLO phenomena.
Second-Order Hyperpolarizability and Susceptibility Calculations of a Series of Ruthenium Complexes
(IEEE, 2013) Karakas, A.; Dag, T.; Taser, M.; Fillaut, J-L; Migalska-Zalas, A.; Sahraoui, B.
The ab-initio quantum mechanical calculations (time-dependent Hartree-Fock (TDHF) method) of a series of ruthenium complexes have been carried out to compute electric dipole moment (mu), dispersion-free and frequency-dependent first hyperpolarizability (beta) values. The one-photon absorption (OPA) characterizations have been also theoretically investigated by means of configuration interaction (CI) method. Our calculated results on the maximum OPA wavelengths and second-order hyperpolarizabilities are in good agreement with the observed values in the literature. According to the results of the TDHF calculations, the investigated molecules exhibit non-zero beta values, and they might have microscopic second-order nonlinear optical (NLO) behaviour. We also give the computational results of the frequency-dependent second-order susceptibilities (X-(2)) for the examined compounds. The calculated results on dynamic (X-(2)). are quite consistent with the previous experimental observations.
Second-order nonlinearities of anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene
(ELSEVIER SCIENCE BV, 2016) Karakaya, M.; Karakas, A.; Taser, M.; Wolska, N.; Arof, A. K.; Sahraoui, B.
Due to the connecting one pi -conjugated group with the two backside donor and acceptor groups, anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene (1) might possess nonlinear optical (NLO) properties. To estimate the potential for second-order NLO behaviour; the electric dipole moments and dispersion-free dipole polarizabilities and first hyperpolarizabilities have been determined by density functional theory (DFT) at B3LYP/6-31++G(d, p) level. Quantum mechanical calculations using time-dependent Hartree-Fock (TDHF) procedure have been utilized to evaluate frequency-dependent second-order nonlinearities of 1. The one-photon absorption (OPA) characterization of 1 has been theoretically obtained by means of configuration interaction (CI) with 6-31G basis set. Our theoretical results on the maximum OPA wavelength, second-order susceptibilities and corresponding microscopic NLO responses are accorded with the previous experimental observations of the investigated compound. The highest occupied molecular orbitals, the lowest unoccupied molecular orbitals and the HOMO-LUMO band gaps for 1 have been also examined by DFT/B3LYP method. (C) 2016 The Authors. Published by Elsevier Ltd.
Structural characterization and second-order nonlinear optical behavior of metal complexes of ferrocene derivative
(MAIK NAUKA/INTERPERIODICA/SPRINGER, 2019) Deveci, P.; Taner, B.; Özcan, E.; Kılıç, Z.; Karakaya, M.; Karakas, A.
In this manuscript, a ferrocene-linked vic-dioxime ligand (LH2) and its metal complexes [Ni(LH)(2), Cu(LH)(2), Co(LH)(2)(H2O)(2), Cd(LH)(H2O)(Cl), and Zn(LH)(H2O)(Cl)] are synthesized, and their structures are studied by spectral methods. Redox behavior of the compounds is studied by cyclic voltammetry (CV). For approaching microscopic second-order nonlinear optical (NLO) behavior of the synthesized ligand and its diamagnetic Cd(II), Zn(II), Ni(II) complexes, the electric dipole moment , static dipole polarizability , and first hyperpolarizability values are computed using ab-initio quantum chemical procedure [finite field (FF)]. The accumulated data indicate that the compounds exhibit non-zero quadratic hyperpolarizability tensor components, implying microscopic NLO phenomena. The HOMOs, LUMOs and the HOMOLUMO band gaps for first and second frontier orbitals of LH2 ligand and its Cd(II), Zn(II), Ni(II) complexes are evaluated by means of the Hartree-Fock (HF) method.
Study of some sensitizers for gel polymer electrolyte based sensitized solar cells (SSCs)
(ELSEVIER, 2019) Mingsukang, M. A.; Hisamuddin, S. N.; Baharun, N. N. S.; Lee, Y. C.; Abidin, Z. H. Z.; Buraidah, M. H.; Karakas, A.
The performance of phthaloychitosan gel polymer electrolyte (GPE) based sensitized solar cells (SSCs) fabricated with different types of sensitizer have been studied in this work. Five types of sensitizer were used viz., curcumin, chlorophyll, (E)-4-hydroxyl-3-((4-iodophenyl)diazenyl)-2H-chromen-2-one (CAD5), (E)-4-hydroxyl-3-((4-methoxyphenyl) diazenyl)-2H-chromen-2-one (CAD7) and cadmium sulphide (CdS). These sensitizers were designated as S1, S2, S3, S4 and S5 respectively. The performance of the sensitized solar cells (SSCs) has been characterized and the experimental results showed that S1 (SSC fabricated with curcumin dye sensitizer) exhibits the best performance with short circuit current density (J(sc)) of 3.18 mA cm(-2), open circuit voltage (V-oc) of 0.41 V, fill factor (FF) 0.57 and power conversion efficiency (PCE) of 0.73%. (C) 2019 Elsevier Ltd. All rights reserved.
Theoretical and experimental investigations on the nonlinear optical properties of gold(III) dithiolene complexes
(ELSEVIER, 2013) Guezguez, I.; Karakas, A.; Iliopoulos, K.; Derkowska-Zielinska, B.; El-Ghayoury, A.; Ranganathan, A.; Batail, P.
Degenerate four-wave mixing (DFWM) experiments have been performed to determine the third-order nonlinear optical (NLO) susceptibilities (chi((3))) of gold(III) maleimide dithiolate tetraphenylphosphonium, (PPh4)[Au(midt)(2)], (Au-P) and gold(III) maleimide dithiolate melamine melaminium hybrid solvate, (C3- N6H6)(C3N6H7+)[Au(midt)(2)](-)center dot 2DMF center dot 2H(2)O, (Au-Mel). Ab-initio quantum mechanical calculations (time-dependent Hartree-Fock (TDHF) method) of Au-P and Au-Mel have been carried out to compute the electric dipole moment (mu), the dispersion-free and frequency-dependent dipole polarizability (alpha) and the second hyperpolarizability (gamma) values. These theoretical calculations are in good agreement with the experimentally obtained results by the DFWM technique. All the investigations show clearly the effect played by the counter ion on the resulting NLO properties of the two gold complexes. (C) 2013 Elsevier B.V. All rights reserved.
Theoretical Calculations of Second and Third-Order Nonlinear Susceptibilities and Their Corresponding Hyperpolarizabilities of a Styrylquinolinium Dye
(IEEE, 2014) Karakas, A.; Ceylan, Y.; Bakalska, R.; Todorova, M.; Sofiani, Z.; Sahraoui, B.
The second (chi((2))(exp)) and third-order (chi((3))(exp)) susceptibilities of a styrylquinolinium dye (1) have been determined utilizing second-harmonic generation (SHG) and third-harmonic generation (THG) techniques, respectively. The reported measurement findings on chi((2))(exp) and chi((3))(exp) have been compared with the theoretical data evaluated here by means of ab-initio quantum mechanical calculations. The electric dipole moments (mu), static dipole polarizabilities (alpha) and first hyperpolarizabilities (beta) have been computed by density functional theory (DFT) at B3LYP/6-311+G(d, p) level. To reveal the frequency-dependent second and third-order microscopic nonlinear optical (NLO) behavior of the title compound, the dynamic dipole polarizabilities, first and second (gamma) hyperpolarizabilities have been theoretically investigated using time-dependent Hartree-Fock (TDHF) method. According to the experimental and theoretical results, the values of susceptibilities and the corresponding microscopic coefficients with large non-zero responses make the examined dye promising candidate for NLO applications.
Theoretical diagnostics of second and third-order hyperpolarizabilities of several acid derivatives
(DE GRUYTER POLAND SP ZOO, 2019) Karakas, A.; Ceylan, Y.; Karakaya, M.; Taser, M.; Terlemez, B. B.; Eren, N.; El Kouari, Y.
The density functional theory (DFT) at B3LYP/6-31G(d) level has been utilized to achieve the electric dipole moment (mu), static dipole polarizability (alpha) and first hyperpolarizability (beta) values for ferulic acid (1) and chenodeoxycholic acid (2). The time-dependent Hartree-Fock (TDHF) technique as a powerful quantum chemical method has been implemented to reveal the dynamic alpha, beta and third-order hyperpolarizabilities (gamma) of the examined compounds. Our computational conclusions have been compared with the results of similar materials in the literature. The first and second frontier molecular orbitals (MOs) and their band gaps have also been investigated by means of DFT.
Two-photon absorption and third-order nonlinear optical characterization of pyrrolo-tetrathiafulvalene derivatives
(SPRINGER, 2014) Karakas, A.; Dag, T.; El Ouazzani, H.; Sebiaai, K.; Boughaleb, Y.
To provide an insight into the third-order nonlinear optical (NLO) behaviour of a series of tetrathiafulvalene (TTF)-based molecules, the third-order NLO properties and two-photon absorption characterizations have been theoretically investigated by means of the time-dependent Hartree-Fock method. According to ab-initio calculation results, the examined molecules exhibit second hyperpolarizabilities with non-zero values, implying microscopic third-order optical nonlinearity. Our computed results are also in good agreement with the previous experimental observations on the title compounds.
Z-Scan Determination and Ab-Initio Computations on Third-Order Optical Nonlinearities of a Styrylquinolinium Dye
(IEEE, 2014) Karakas, A.; Sofiani, Z.; Ceylan, Y.; Taser, M.; Bakalska, R.; Todorova, M.; Sahraoui, B.
In order to elucidate the third-order nonlinear optical (NLO) phenomena of the styrylquinolinium dye (1), the nonlinear absorption parameter (beta) and third-order susceptibility (chi((3))) have been measured using the Z-scan measurements. The one-photon absorption (OPA) and two-photon absorption (TPA) characterizations have been determined by configuration interaction (CI) and time-dependent Hartree-Fock (TDHF) methods, respectively. The averaged (isotropic) second hyperpolarizability () allows the determination of the third-order optical response. The ab-initio calculation on with non-zero value reveals that the title dye has relatively good third-order NLO properties. The calculated results of 1 on OPA wavelength, TPA cross-section (delta(omega)) and third-order susceptibility are in reasonable agreement with its experimental data.

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