Pseudopotential
Mostrando 1-12 de 26 artigos, teses e dissertações.
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1. Pseudopotential Study of CdTe Quantum Dots: Electronic and Optical Properties
The present contribution reports on the electronic and optical properties of zinc-blende CdTe quantum dots using a pseudopotential approach. Our findings showed that the predicted nano-structured direct band gap is significantly increased relative to the bulk one. For a nanocrystal diameter in the range 1.2-5 nm, the refractive index and dielectric constant
Mat. Res.. Publicado em: 30/05/2019
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2. Band Structure, Charge Distribution and Optical Properties of AlPxSb1-x Ternary Semiconductor Alloys
The present contribution studies on the composition dependence of the electronic and optical properties of the zinc-blende alloy system AlPxSb1-x. The calculations are performed using a pseudopotential approach under the virtual crystal approximation. Features such as electronic band structure, energy band-gaps, refractive index, dielectric constants and val
Mat. Res.. Publicado em: 21/05/2018
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3. Estudo teórico de efeitos de solvatação do tetraidrofurano sobre um mecanismo modelo de Suzuki-Miyaura / Theoretical study of the effects of tetrahydrofuran s solvation over a Suzuki-Miyaura s model mechanism
Utilizando a implementação do método da coordenada geradora discretizada nos orbitais atômicos, conjuntos de bases adaptados ao pseudopotencial de caroço SBKJC (conjuntos GBSMCS) foram desenvolvidos, validados e utilizados no estudo de possíveis efeitos de solvatação do tetraidrofurano sobre um mecanismo modelo de Suzuki-Miyaura. As metodologias de v
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/02/2011
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4. Structural studies of liquid alkaline-earth metals: A molecular dynamics approach
In the present research article we have studied various properties like binding energy, the pair distribution function g(r), the structure factor S(q), specific heat at constant volume, and coordination number of alkaline-earth metals (Be, Mg, Ca, Sr, and Ba) near melting point temperature using molecular dynamics (MD) simulation technique with a pseudopoten
Brazilian Journal of Physics. Publicado em: 2010-06
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5. Graphene to graphite: electronic changes within DFT calculations
Calculations based on the first-principles pseudopotential plane-wave method and density-functional theory are performed to investigate the electronic properties of graphene, bilayer graphene, multilayer graphene, and graphite. From an analysis of the electronic band structure close to the Fermi level, we have quantified the gradual change in the Fermi surfa
Brazilian Journal of Physics. Publicado em: 2009-12
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6. Análise teórica da superfície Si(111)-(7x7)
In this work, wecarry out theoretical study of the silicon surface reconstruction (7x7) grown in the [111] direction, denoted by Si(111)(7x7), using the Density Functional Theory formalism, within the Local Density Approximation (LDA) for the exchange correlation term. The interaction with the valence electrons and the core ion (nucleus more core electrons)
Publicado em: 2007
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7. Adsorção de bifenil na superfície de Si (001) por um método de primeiros princípios
Nesse trabalho fazemos um estudo da adsorção de moléculas de bifenil sobre a superfície de silício crescida na direção (001). Utilizamos cálculos de primeiros princípios (ab initio), dentro do formalismo da Teoria do Funcional de Densidade (DFT). Dentro do formalismo da DFT, utilizamos aproximação da densidade local (LDA) e aproximação de gradie
Publicado em: 2007
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8. AdsorÃÃo de bifenil na superfÃcie de Si (001) por um mÃtodo de primeiros princÃpios
Nesse trabalho fazemos um estudo da adsorÃÃo de molÃculas de bifenil sobre a superfÃcie de silÃcio crescida na direÃÃo (001). Utilizamos cÃlculos de primeiros princÃpios (ab initio), dentro do formalismo da Teoria do Funcional de Densidade (DFT). Dentro do formalismo da DFT, utilizamos aproximaÃÃo da densidade local (LDA) e aproximaÃÃo de gradie
Publicado em: 2007
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9. AnÃlise teÃrica da superfÃcie Si(111)-(7x7)
Neste trabalho, realizamos o estudo teÃrico da reconstruÃÃo (7x7) da superfÃcie de SilÃcio crescida na direÃÃo [111], denotada por Si(111)â(7x7), utilizando para isto o formalismo da Teoria do Funcional da Densidade, com a AproximaÃÃo da Densidade Local (LDA - LocalDensityApproximation) para o termo de trocaâcorrelaÃÃo. A interaÃÃo entre os el
Publicado em: 2007
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10. Glycine adsorption on silicon (001)
In this work we employ the state of the art pseudopotential method, within a generalized gradient approximation to the density functional theory, to investigate the dissociative adsorption process of glycine on the silicon surface. Our total energy calculations indicate that the chemisorption of the molecule is as follow. The gas phase NH2-C2H2-OOH adsorbs m
Brazilian Journal of Physics. Publicado em: 2006-06
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11. The oxidation mechanism of CdTe (110) surface
Using a first-principles pseudopotential technique within a generalized gradient approximation of the density functional theory, we have investigated the mechanism of adsorption of molecular oxygen on the CdTe(110) surface. The determination of the more favorables structures and their formation through the activation barrier analysis indicates that the forma
Brazilian Journal of Physics. Publicado em: 2006-06
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12. Theoretical study of the internal elimination of xanthates using ONIOM additivity and pseudopotentials / Estudo teorico do mecanismo de eliminação interna de xantatos usando o metodo aditivo de energia atraves de ONIOM com pseudopotencial
The gas-phase internal elimination (Ei) reaction of xanthates and the decomposition of xanthic acid have been investigated using ONIOM Additivity Expression and Pseudopotential, ONIOM[CCSD(T)/CEP-311 (2d,f):MP2/CEP-31G//MP2/CEP-31G]. The higest leveI representation was calculated by means of CCSD(T)/CEP-31G and electronics and sterics effects by MP2/CEP-31G.
Publicado em: 2006