Vibrational Frequencies
Mostrando 1-12 de 69 artigos, teses e dissertações.
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1. VIBRATIONAL SPECTROSCOPIC INVESTIGATION AND MOLECULAR STRUCTURE OF A 5α-REDUCTASE INHIBITOR: FINASTERIDE
By way of Density Functional Theory (DFT)-based computational methods with commercially available software, the computational work of which about the molecular properties, the vibrational modes and vibrational frequencies of finasteride were accomplished for the first time. In order to gain a deeper and more thorough understanding of the molecular structure
Quím. Nova. Publicado em: 2020-05
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2. Pesquisas em políticas de comunicação em contextos de crise
By way of Density Functional Theory (DFT)-based computational methods with commercially available software, the computational work of which about the molecular properties, the vibrational modes and vibrational frequencies of finasteride were accomplished for the first time. In order to gain a deeper and more thorough understanding of the molecular structure
Intercom, Rev. Bras. Ciênc. Comun.. Publicado em: 2020-05
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3. New hybrid approach for free vibration and stability analyses of axially functionally graded Euler-Bernoulli beams with variable cross-section resting on uniform Winkler-Pasternak foundation
Abstract In this paper, a new hybrid approach is presented based on the combination of the power series expansions and the Rayleigh-Ritz method for stability and free vibration analyses of axially functionally graded non-uniform beams resting on constant Winkler-Pasternak elastic foundation. In the proposed novel technique, the power series approximation is
Lat. Am. j. solids struct.. Publicado em: 08/04/2019
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4. 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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5. Adsorción y oxidación de monóxido de carbono en una lamina de ß-grafino: Estudio teórico
ABSTRACT This work presents a study, based on the Density functional theory (DFT), of the adsorption and oxidation of CO on a free platinum catalyst constituted from a sheet of Graphyne. Graphyne is a new allotrope of carbon, its structure is two-dimensional and is constituted by a monolayer of carbon atoms with sp-sp2 hybridization. Depending on the differe
Matéria (Rio J.). Publicado em: 19/07/2018
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6. Preparation and Characterization of the Structural, Optical, Spectroscopic and Electrical Properties of Pr2O5 doped Borate Glass
Abstract We have successfully synthesized Pr2O5 doped borate glasses by conventional rapid melt quench method. The XRD pattern indicates the amorphous nature of Pr2O5 doped borate glass. An optical property of prepared borate glass was studied using the Photoluminescence spectrum. Determination and differentiation of the various vibrational modes were done u
Mat. Res.. Publicado em: 18/07/2016
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7. Exploración estocástica de las superficies de energía potencial de dímeros cis-trans y trans-trans del ácido fórmico
Potential energy surface (PES) of cis-trans and trans-trans formic acid dimers were sampled using a stochastic method, and the geometries, energies, and vibrational frequencies were computed at B3LYP/6-311++G(3df,2p) level of theory. The results show that molar free energy of dimerization deviated up to 108.4% when basis set superposition error (BSSE) and ze
Quím. Nova. Publicado em: 2014
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8. Application of computational chemistry methods to obtain thermodynamic data for hydrogen production from liquefied petroleum gas
The objective of this study was to estimate thermodynamic data, such as standard enthalpy, entropy and Gibbs free energy changes of reaction and, consequently, chemical equilibrium constants, for a reaction system describing the hydrogen production from Liquefied Petroleum Gas (LPG). The acquisition of those properties was made using computational chemistry
Braz. J. Chem. Eng.. Publicado em: 2013-03
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9. El estudio y enseñanza de los modos vibracionales de la molécula triatómica
This work shows that by means of knowledge of the general theory of small oscillations is possible to solve analytically the vibrational modes of the triangular molecule, and from comparative results between the linear and triangular molecule can access the dynamics of the triangular molecule and simplify the analysis. To illustrate this, is modeled mechanic
Revista Brasileira de Ensino de Física. Publicado em: 2011-03
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10. 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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11. Estudo da adsorção do líquido iônico [BMIM]+[BF4]sobre γ-Al2O3 por cálculos ab initio
Ionic liquids are, by definition, salts formed by an organic cation and an inorganic anion, with a low melting point. An important application of ionic liquids is that they can replace conventional solvents. Recently, they were also used as cocatalysts (in the form of solvents) for metallic clusters, in the process of removal of aromatics from petroleum. The
Publicado em: 2010
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12. Abordagem da química das fragrâncias de almíscares por estudos teóricos e espectroscópicos
Both pentadecanolide and exaltolide compounds were widely used by the perfume industry for their soft and persistent odor of musks, with high fixative power. However, once they have animal origin (customarily found in anal glands of the musk deer), their usage is controlled by high costs and, also, by environmental activist groups and by all animal lovers. A
Publicado em: 2010