First Hyperpolarizability
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. Hirshfeld Surfaces and Nonlinear Optics on Two Conformers of a Heterocyclic Chalcone
Heterocyclic chalcones have been prominent in the scientific community due to various biological activities reported for these compounds. The structural knowledge of heterocyclic chalcones can help in the understanding of their mechanism of action. The Hirshfeld surfaces were used to study the supramolecular arrangement of two conformers present into asymmet
J. Braz. Chem. Soc.. Publicado em: 2018-02
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2. Design de novos derivados da ftalocianina de zinco para emprego em óptica não-linear
O presente trabalho tem como objetivo a proposição, por Engenharia Molecular, de derivados da Ftalocianina de Zinco com características desejáveis para aplicação em fotônica. Para caracterizar esses compostos, foi empregado um estudo teórico, incluindo estrutura eletrônica, geometria, energia dos estados, transições eletrônicas e algumas propried
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/02/2012
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3. Efeitos de solvente sobre propriedades elétricas de compostos mesoiônicos / Solvent effects on electrical properties of mesoionic compounds
In this work we study the electric properties of mesoionic compounds in the gaseous phase in different solvents, with a special attention to the first hyperpolarizability (β ). The Hartree-Fock (HF) method and the second-order MøllerPlesset perturbation theory (MP2) were used to describe the electronic structure. The solvent effects were modelled using
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/07/2010
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4. Cálculo de propriedades elétricas lineares, não-lineares e estruturais da molécula HOBr
Ab initio, also known as first principles, computational methods are highly esteemed because of the accuracy of the results produced and the fact that they are not built upon any empirical models, therefore considered reliable. Although, these positive remarks carry along a heavy computational effort, which increase very rapidly with the number of basis func
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/04/2010
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5. Estudo teórico de propriedades ópticas não-lineares de nanotubos de carbono de parede única quimicamente modificados
Structure and first hyperpolarizability for a series of armchair a(5,5) chemically modified carbon nanotubes (CNT) were calculated at semiempirical and density functional levels of theory. The 4,4´-substituted stilbenes were selected as chromophore with substituents at position 4´ set to X=NO2, H, Cl, OH and NH2. The calculated values for static first hype
Química Nova. Publicado em: 2009
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6. Caracterização espectroscópica e por modelagem mecânico-quântica, de compostos com potencial aplicação em dispositivos ópticos não-lineares
In the present work, the compounds 1-(3,4,5-trimethoxiphenil)-2-(2- tienyl) -5-(4-nitrophenylazo) pirrol (compound 1) and 5-dicianovinyl-5- piperidine-5,2:5:2- tertiophene (compound 2), were characterized using a combination of spectroscopic measurements and quantum mechanical calculation, aiming to evaluate if they present the necessary requisites for appli
Publicado em: 2009
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7. Development and application of the pulse train hyper-Rayleigh scattering technique. / Desenvolvimento e aplicação da técnica de hiper Rayleigh com trem de pulsos
This thesis reports an extension of the Hyper-Rayleigh scattering technique (HRS) and its application to study the mechanisms that contribute to the molecular first hyperpolarizabilities (). We use a Nd:YAG laser, Q-switched and mode-locked, as pumping beam to excite the samples. The laser delivers 100 ps pulses modulated by a Q-switch envelope, and the outp
Publicado em: 2008
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8. CaracterizaÃÃo Ãptica de materiais nanoestruturados por tÃcnicas de geraÃÃo de segundo e terceiro harmÃnico
This work is dedicated to the optical characterization of nanostructured materials that are of interest for non-linear optics, optoelectronics and nanophotonics. The hyper- Rayleigh scattering (HRS) technique and the third harmonic generation (THG) technique were used. The materials investigated were a glass-ceramics containing sodium niobate (NaNbO3) nanocr
Publicado em: 2007
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9. Estrutura eletronica e polarizabilidades de betainas
This thesis is dedicated to a theoretical study of the electronic structure and optical properties of betaine molecules carried at the semiempirical and ab initio levels. The charge distribution, the dipole moment and the linear (a) and first nonlinear (Ã) polarizabilities of a total of 66 betaine molecules belonging to 6 different families were calculated.
Publicado em: 2007
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10. Vibrational contribution to dipole polarizability and first hyperpolarizability of LiH
The role played by electron correlation and vibrational correction on the polarizability of the LiH molecule is demonstrated. We present results for the dipole moment, polarizability and first hyperpolarizability of the LiH molecule obtained through many-body perturbation-theory, coupled-cluster and quadratic configuration interaction methods. Our best resul
Química Nova. Publicado em: 2006-12
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11. Study of nonlinear optics property of amino acid / Estudo de propriedades ópticas não lineares de aminoácidos
In this work we have studied nonlinear optical properties of amino acids using femtosecond laser pulses. The nonlinear index of refraction (nz) of L-alanine, L-proline, L-serine, L-threonine and L-arginine in aqueous solution have been determined. Also, the influence of pH in the magnitude of nz of amino acids in solution has been studied. Besides, we have d
Publicado em: 2003
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12. Nonlinear optical properties of aniline oligomers / Propriedades ópticas não-lineares de oligômeros de anilina
We report on the study of electronic optical non linearities in two aniline oligomers: dimer and the tetramer. Four tetramer concentrations were measured, pure and also 33 and 100% doped; one of dimer non doped another 100% doped. The solutions were prepared using dimethyl sulfoxide (DMSO) as solvent and the doping was performed with hydrochloric acid. The s
Publicado em: 2002