Intramolecular Charge
Mostrando 1-12 de 37 artigos, teses e dissertações.
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1. SYNTHESIS, ELECTRONIC AND SPECTRAL PROPERTIES OF NEW 1,3,4-THIADIAZOLE COMPOUNDS AND THE SPECTRAL ANALYSIS OF THEIR CONFORMERS USING DENSITY FUNCTIONAL THEORY
In this study, new 1,3,4-thiadiazole compounds were synthesised and characterised by FT-IR, 1H-NMR, UV-vis spectroscopy and elemental analysis, Furthermore, the relationship between the electronic and spectral data of the 16 conformers of each compound was investigated by theoretical calculations; the theoretical data were compared with the experimental resu
Quím. Nova. Publicado em: 2019-02
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2. A Water Soluble Naphthalimide-Based Chemosensor for Fluorescent Detection CN- in Pure Water and Its Application in Practical Samples
By rationally introducing aromatic carboxyl functionalized 1,8-naphthalimide, a water soluble fluorescent chemosensor (DA) was successfully synthesized. It could selectively and sensitively detect CN- in pure water via an intramolecular charge transfer to twisted intramolecular charge transfer (ICT-TICT) state change mechanism. The detection limit of the che
J. Braz. Chem. Soc.. Publicado em: 2018-07
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3. Molecular Electronic Topology and Fragmentation Onset via Charge Partition Methods and Nuclear Fukui Functions: 1,1-Diamino-2,2-dinitroethylene
We investigated theoretically the ground state electronic structure and the onset of molecular fragmentation of 1,1-diamino-2,2-dinitroethylene (FOX-7) using density functional theory. The molecular charge density was analyzed via two partition methods: the distributed multipole analysis (DMA) and the deformed atoms in molecules (DAM). In this framework, the
J. Braz. Chem. Soc.. Publicado em: 2015-05
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4. Modulating the electronic structure of amino acids: interaction of model lewis acids with anthranilic acid
On the basis of theoretical B3LYP calculations, Yáñez and co-workers (J. Chem. Theory Comput. 2012, 8, 2293) illustrated that beryllium ions are capable of significantly modulating (changing) the electronic structures of imidazole. In this computational organic chemistry study, the interaction of this β-amino acid and five model Lewis acids (BeF1+, Be2+,
Quím. Nova. Publicado em: 2014
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5. Synthesis, characterization and computational studies of (E)-2-{[(2-aminopyridin-3-yl)imino]-methyl}-4,6-di-tert-butylphenol
(E)-2-{[(2-Aminopyridin-3-yl)imino]-methyl}-4,6-di-tert-butyl-phenol ( 3: ), a ligand containing an intramolecular hydrogen bond, was prepared according to a previous literature report, with modifications, and was characterized by UV-vis, FTIR, ¹H-NMR, 13C-NMR, HHCOSY, TOCSY and cyclic voltammetry. Computational analyses at the level of DFT and TD-DFT were
Quím. Nova. Publicado em: 2014
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6. Preparação e estudo fotofísico de nanopartículas de sílica marcadas com compostos fluorescentes / Preparation and photophysical study of silica nanoparticles grafted with fluorescent compounds
Photophysical behavior of 9-aminoacridine (9AA) and derivatives, safranine O, auramine and 9-vinylanthracene was investigated, in silica particles. Firstly, commercial silica was modified and grafted with acridinic dyes; however, photophysical studies became unviable, due to its morphology. Silica nanospheres were prepared by Stöber method, with mean diamet
Publicado em: 2009
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7. 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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8. SÃntese, caracterizaÃÃo e propriedades fotocrÃmicas da sais derivados do Ãcido N-(3,5-dinitrobenzoil)-α-fenilglicina
The preparation and characterization of salts derived from N-(3,5- dinitrobenzoyl)-α-phenylglycine was carried out by using protonated amines as counter-ion, as follows: NH4 + (DNBAm), (CH3-CH2-)2NH2 + (DNBD), (CH3-CH2-CH2- )NH3 + (DNBP), (CH3-CH2-CH2-CH2-)NH3 + (DNBBu) and (CH3-CH2-)3NH+ (DNBT). These salts showed photocromic effect with ultraviolet (U
Publicado em: 2008
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9. Fluorescence modulation of acridine and coumarin dyes by silver nanoparticles / Modulação de fluorescência de amino coumarinas e acridinas por nanopartículas de prata
Nanopartículas de prata foram preparadas pela redução química de íons prata (AgNO3) por borohidreto de sódio (NaBH4) na presença de poli-(N)-vinil-2-pirrolidona em solução de álcoois de cadeia curta. As nanopartículas de prata apresentaram maior estabilidade em 2- propanol, e o diâmetro aproximado das nanopartículas Ag0 obtidas neste solvente é
Publicado em: 2007
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10. 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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11. "Intramolecular charge and hydrogen bon transfer in 9-aminoacridine derivatives" / "Transferência de carga e ligação de hidrogênio intramolecular em derivados de 9-aminoacridina"
Neste trabalho, o corante 9-aminoacridina foi derivatizado com compostos vinílicos que possuem grupos retiradores de elétrons. A incorporação destes leva à mudanças nas propriedades fotofísicas dos derivados, tais como deslocamentos para regiões de menor energia nos espectros de absorção e emissão, sugerindo a presença de transferência de carga
Publicado em: 2006
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12. Espectroscopia vibracional, Raman ressonante e eletrônica de nitroderivados em sistemas conjugados / Vibrational, resonance Raman and electronic spectroscopies of nitroderivatives in conjugated systems
No presente trabalho foram investigados vários sistemas moleculares contemplando um ou mais grupos NO2 com características fortemente elétron atraentes, e por outro lado um grupo fortemente elétron doador (NH2, OH ou N3H) conectados através de um anel benzênico ou piridínico. A caracterização das propriedades de transferência de carga intramolecula
Publicado em: 2005