Solvation Models
Mostrando 1-12 de 25 artigos, teses e dissertações.
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1. FASES ESTACIONÁRIAS DE LÍQUIDOS IÔNICOS EM CROMATOGRAFIA GASOSA: FUNDAMENTOS, AVANÇOS RECENTES E PERSPECTIVAS
Since their original discovery in 1914, ionic liquids (IL) have been widely examined and explored in chemistry due to their unique physical and chemical properties. Ionic liquids are collectively known as organic salts and have melting points of 100 °C or under. The molten salts most employed in analytical chemistry, including gas chromatography (GC), consi
Quím. Nova. Publicado em: 2016-01
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2. Estimating reaction constants by ab initio molecular modeling: a study on the oxidation of phenol to catechol and hydroquinone in advanced oxidation processes
Molecular modeling is growing as a research tool in Chemical Engineering studies, as can be seen by a simple research on the latest publications in the field. Molecular investigations retrieve information on properties often accessible only by expensive and time-consuming experimental techniques, such as those involved in the study of radical-based chain rea
Brazilian Journal of Chemical Engineering. Publicado em: 2012-03
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3. Espectroscopia de alcalinos em Hélio líquido / Spectroscopy of Alkali in Liquid Helium
Alkali atoms are good probes for the understanding of liquid He properties. As such considerable experimental attention has been devoted to the analysis of the changes of line position and widths of the absorption spectra of alkali atoms in liquid He environment. On the theoretical side, several studies have used simplified models such as bubble and cluster
Publicado em: 2010
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4. Estudos conformacional de ésteres metílicos de alguns aminoácidos através das espectroscopias no infravermelho, de RMN e cálculos teóricos / IR, NMR and theoretical investigation on the conformational analysis of some amino acids methyl esfers
Este trabalho apresenta estudos teóricos e experimentais sobre estabilidade conformacional de ésteres metílicos de alguns aminoácidos (glicina, alanina, prolina e ácido aspártico) por meio de espectroscopia vibracional e cálculos teóricos da estrutura eletrônica. Os cálculos teóricos foram efetuados com o método ab initio em nível MP2 e com o da
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 17/12/2009
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5. Termodinâmica de sistemas fullerênicos em soluções / Thermodynamic systems fullerenic solutions
In this work, we present a computational study of the solvation process of the C60 fullerene and its hydroxylated derivate, the fullerenol C60(OH)24, in aqueous environment and organic solvents, using classical molecular dynamics simulations. Diverse sets of parameters to the Lennard-Jones interaction potential have been utilized in simulations of fullerenes
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/09/2009
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6. Estimativa dos pKa da Rutina empregando modelos semi-empíricos de cálculo mecânico-quântico
Neste trabalho, propriedades moleculares e termodinâmicas da molécula da rutina na fase gasosa e em meio aquoso, com a inserção de moléculas discretas de água em posições específicas, foram estudadas por meios de cálculos mecânico quânticos, utilizando especificamente como ferramenta os métodos semi-empíricos AM1 e o PM6 para o cálculo teóric
Publicado em: 2009
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7. Modelos contínuos do solvente: fundamentos
Continuum solvation models are nowadays widely used in the modeling of solvent effects and the range of applications goes from the calculation of partition coefficients to chemical reactions in solution. The present work presents a detailed explanation of the physical foundations of continuum models. We discuss the polarization of a dielectric and its repres
Química Nova. Publicado em: 2006-06
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8. Estrutura e propriedades de elipticinas
The ellipticines constitute a broad class of molecules with antitumor activity. In the present work we analyzed the structure and properties of a series of ellipticine derivatives in the gas phase and in solution using quantum mechanical and Monte Carlo methods. The results showed a good correlation between the solvation energies in water obtained with the c
Química Nova. Publicado em: 2005-02
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9. Estudo do método de equalização da eletronegatividade no cálculo de energias livres de solvatação GBEEM-ELR / Study of electronegativity equalization method in the calculation of solvation free energies GBEEM-ELR
O método de equalização da eletronegatividade (Electronegativity Equalization Method, EEM), fundamentado em teoria do funcional da densidade eletrônica, foi combinado à aproximação de Born generalizada para moléculas (Generalized Born, GB), e denominado GBEEM (Dias et al., 2002). Os momentos de dipolo permanente no vácuo e em meio condensado (consta
Publicado em: 2005
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10. The interpretation of water anomalies in terms of core-softened models
In the first part of this paper I review the understanding of anomalous properties of water in terms of particles interacting by core-softened potentials. I discuss the origin of the bulk anomalies in terms of the two different configurations of neighbor particles: low energy-high volume and high energy-low volume. In the second part I study some anomalies o
Brazilian Journal of Physics. Publicado em: 2004-03
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11. Isomerismo rotacional por ressonancia magnetica nuclear e calculos teoricos : [alfa]-haloacetatos de metila
The present work reports the NMR and theoretical calculations of rotational isomerism in methyl a-haloacetates (halo = chlorine, bromine and iodine). The results were complemented with infrared spectroscopy. Ab initio calculations were performed with GAUSSIAN 98 program, using DFT/B3LYP and MP2 theories at different levels for the chlorine and bromine-deriva
Publicado em: 2003
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12. Solvation, water permeation, and ionic selectivity of a putative model for the pore region of the voltage-gated sodium channel.
This paper describes a molecular dynamics and molecular mechanics study of the solvation and selectivity of the narrow pore and vestibule region of a model-built structure for the voltage-gated sodium channel. The particular structure used was one proposed by Guy and Durell. However, many of the features we saw would likely be shared with other possible mode