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Synthesis and investigation of nonlinear optical properties of Para Red: Z-scan technique end quantum mechanical calculations

Mostaghni F., Abed Y.

Materials Science Poland

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2018

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Vol. 36, No. 3

445--451

EN

In this study, we present a systematic study of linear and nonlinear optical properties of Para Red with the aim of Z-scan technique and quantum mechanical calculations. The Z-scan experiments were performed using a 532 nm Nd: YAG (SHG) CW laser beam. Para Red exhibited a strong nonlinear refractive index, nonlinear absorption coefficient and third-order nonlinear susceptibility 3.487 × 10-6 cm2/W, 2.341 × 10-1 cm/W and 2.157 × 10-4 esu, respectively. Also, quantum chemical analysis was used for the calculation of the dipole moment µ, dipole polarizability α, anisotropy of polarizability Δα and molecular hyperpolarizabilities (β, γ). The results revealed that Para Red has large first and second hyperpolarizabilities. However, from the obtained results, it was found that Para Red can be a promising material for applications in the development of non-linear optical materials.

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Energy storage: dielectrophores – molecules with non-linear polarizability

Mourokh L., Lazarev P.

Advances in Materials Science

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2017

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Vol. 17, nr 4(54)

14--21

EN

We examine the feasibility of film capacitors based on dielectrics with high non-linear polarizability as energy storage devices. Capacitors with increased energy density can be built by using composite materials with aromatic molecules (high polarizability) and envelope of alkyl tails (high resistivity). We determine the impact of the second order non-linearity onto energy density and translate high energy density requirements into molecular parameters necessary for high-performance capacitors. The relationship of permittivity and molecular polarizability is obtained by means of the non-linear Clausius–Mossotti equation. In order to demonstrate the the selection process for the molecular composition of dielectrophores, we compare several molecules, using quantum chemistry algorithms (Gaussian09). Starting from Langhals perylene (LP), we proceed with the nitrophenyl-perylene having one NH2 group (donor) and one NO2 group (acceptor). We show that, while their linear polarizabilities are comparable, the hyperpolarizabilities differ by several orders of the magnitudes. Two NH2 and NO2 groups can be attached to the nitro-naphthalene-perylene further increasing of the hyperpolarizability. Even larger polarization can be achieved by additional rylene groups increasing the polarizable electronic mass. We demonstrate that with such molecular engineering, capacitors can have the energy density which is attractive for practical applications.

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Chemia kwantowa w molekularnej optyce nieliniowej

Wielgus M., Kozłowska J., Bartkowiak W.

Wiadomości Chemiczne

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2012

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[Z] 66, 1-2

1-18

EN

We review quantum-chemical methodologies based on simple two- and three- state models for molecular hyperpolarizabilities and two-photon cross-sections. In this article we show that simplified few-state models, obtained from sum -over-states formalism, are important tools for investigations structure-property relationships for various type of đ-conjugated compounds. These relationships are important for rational design of molecules with large nonlinear optical response

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Hyperpolarizalities of pyridine derivatives and their protonated species: ab initio studies

Latajka Z., Gajewski G., Ratajczak H., Venturini J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 1

1-4

EN

The first hyperpolarizability values of pyridine derivatives and their proto-nated species have been calculated using ab intio (STO-3G) method. The effect of proto-nation on these values is discussed.

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Quantum-Chemical Calculations of First-Order Hyperpolarizability of Epoxy Oligomers with Chromophore in the main Chain

Balakina M., Ilyazov M. F., Zuev M. B.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 9

1199-1209

EN

Results of quantum-chemical calculations of first hyperpolarizabilities for a number of epoxy oligomers with nonlinear optical (NLO) chromophores incorporated into the main chain as a side group are presented. These oligomers simulate the internode chains of cross-linked NLO materials, which are the most promising candidates for application in optoelectronics. The attempt is made to establish a relationship between the hyperpolarizability and the conformation of the bearing chain in the vicinity of the chromophore. The structure and conformation of the oligomer chain are shown to affect significantly the longitudinal hyperpolarizability of the chromophore. Some recommendations are given to obtain hyperpolarizability values optimal for the studied molecular systems.

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Local Fields and Distributed Response : Electric Susceptibility Calculations for Molecular Materials

Munn R., Papadopoulos M. G, Reis H.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

155-165

EN

Progress in the last 25 years towards realistic theoretical calculation of linear and non-linear electric susceptibilities of molecular materials is reviewed. Key issues are proper treatment of local electric fields and of the spatial distribution of molecular response. The local fields contribute directly to the susceptibilities and indirectly by modifying the molecular response in the material. Distributing molecular dipolar response over equivalent submolecules gives good results if enough submolecules are used. Fully distributed response including charge transfer within molecules can approach experimental accuracy.

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Modelowanie własności nieliniow optycznych monomerów z ugrupowaniem chromoforowym

Diduch K., Kucharski S.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2001

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Vol. 50, nr 23

355-358

PL

Przy użyciu programu obliczeniowego GAUSSIAN 98 przeprowadzone zostały obliczenia kwantowo-chemiczne polaryzowalności [alfa], hiperpolaryzowalności [beta]° oraz momentu dipolowego [mi] dla benzoimidazolowych, bbenzoitazolowych i etylokarbazolowych pochodnych diazowych p-nitroaniliny, sulfatiazolu oraz sulfadiazyny. Najwyżwsze wartości [beta]° otrzymano dla pochodnych etylokarbazolowych (CARB-1) 63,56 10-30 esu, najniższe zaś dla pochodnych benzoimidazolowych (BIM-2) 19,70 10-30 esu. Wykazano wpływ budowy cząsteczki chromoforu zarówno na wielkość drugiej hiperpolaryzowalności jak i wielkości kryterium FOM (figure of merit). Udział wielkości [beta]° w kryterium FOM dla wszystkich chromoforów z wyjątkiem CARB-1 zawiera się w granicach 0,5-5%.

EN

The polarizability [alfa], first hyperpolarizability [beta]° and dipole moments [mi] of benzoimidazoles, benzothiazoles and ethylcarbazoles derivatives of p-nitroaniline, sulfathiazole and sulfadiazine was evaluated by ab initio (GAUSSIAN 98) quantum-chemical calculations. The highest values of [beta]° were obtained for ethylcarbazoles (CARB-1) 63,56 10-30 esu, the lowest results were obtained for benzoimidazole derivatives (BIM-2) 19,70 x 10-30 esu. Basing of the results of the quantum-chemical calculations the influence of the molecular structure of chromofores on hyperpolarizobility and FOM (figure of merit) was discussed. For the chromofore in question the contribution of [beta]° in FOM is in range of 0,5-5%, except for CARB-1.