Local Density Approximation
Mostrando 1-12 de 34 artigos, teses e dissertações.
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1. Temperature influence on mobility and charge density model of photovoltaic cells
abstract Photovoltaic (PV) devices that capture the energy provided by the sun have great potential as renewable energy sources. However, the input parameters such as the luminous intensity and temperature of the solar cells tend to influence the operating characteristics in the solar panels. The inherent physical processes that cannot be altered limit the e
Rev. Bras. Ensino Fís.. Publicado em: 18/02/2019
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2. HIGH PRESSURE BEHAVIOR OF CRYSTALLINE DIHYDROXYLAMMONIUM 5,5'-BISTETRAZOLE-1,1'-DIOLATE: FIRST-PRINCIPLES STUDY
Density functional theory (DFT) periodic calculations were performed to study the geometrical and electronic structures of energetic compound dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) under the pressure ranging from 0 to 400 GPa. The optimized crystal structure by the local density approximation (LDA) with CA-PZ functional matches well with
Quím. Nova. Publicado em: 2017-10
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3. A CONCEPTUAL DFT STUDY OF THE CHEMICAL REACTIVITY OF MAGNESIUM OCTAETHYLPORPHYRIN (MgOEP) AS PREDICTED BY THE MINNESOTA FAMILY OF DENSITY FUNCTIONALS
The Minnesota family of density functionals has been assessed for the calculation of the molecular structure and electronic properties of a Mg(II)-porphyrin, namely Magnesium Octaethylporphyrin (MgOEP). Several global descriptors arising from Conceptual DFT have been calculated through a ΔSCF procedure, and by means of the HOMO and LUMO frontier orbitals. O
Quím. Nova. Publicado em: 2017-05
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4. Ab. initio study of the structural, elastic, electronic and optical properties of Cu3N
Electronic, optical, elastic, properties of Copper nitride (Cu3N) in cubic anti- ReO3 phase have been studied using the full-potential augmented plane waves (FP-LAPW) within density functional theory (DFT) framework. Generalized gradient approximation (GGA), local density approximation (LDA), Perdew - Burke - Ernzerhof generalized parameterization of gradien
Mat. Res.. Publicado em: 01/04/2014
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5. Analisys of the atomic orbitals spin information in the calculation of semiconductors strucutures properties / Análise da informação do spin dos orbitais atômicos no cálculo de propriedades de estruturas semicondutoras
O presente trabalho é um estudo sobre a importância da informação dos orbitais atômicos no cálculo de propriedades optoeletrônicas de heteroestruturas semicondutoras de baixa dimensionalidade. O trabalho é dividido em duas partes: na primeira parte, é estudada a simetria de reversão temporal no hamiltoniano k . p, analisando a preservação da info
Publicado em: 2010
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6. New functionals for the anisotropic Heisenberg model / Novos funcionais para o modelo de Heisenberg anisotrópico
The Heisenberg Model is generally recognized in the study of electromagnetism with origin in localized magnetic moments. Similar to the well known classical Ising model, it incorporates, however, quantum flutuations. We are interested in antiferromagnetic systems described by the Heisenberg Hamiltonian with exchange anisotropy and, eventually, non-null magne
Publicado em: 2008
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7. THEORETICAL STUDY OF THE STABILITY AND ELECTRONIC PROPERTIES IN THE DEFECTS IN GaN NANOTUBES / ESTUDO TEÓRICO DA ESTABILIDADE E PROPRIEDADES ELETRÔNICAS DE DEFEITOS EM NANOTUBOS DE GaN
The stability and electronic properties of antisities, vacancies and substitutional Si and C impurities in GaN nanotubes are studied using spin-polarized density functional theory within the local density approximation (LDA) to the exchange-correlation functional. We investigated these defects in both nanotubes the zigzag (10,0)and the armchair (6,6), which
Publicado em: 2008
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8. CaracterizaÃÃo energÃtica e estrutural da interaÃÃo DNA-cisplatina pela teoria do funcional da densidade
Study of the DNA-cisplatin system using the Density Functional Theory(DFT), compares the eficiency of the correlation and exchange functionals LDA and GGA (PBE) in the simulation of the nitrogen bases as well as the basis sets DZP and DZ. Taking DZP and LDA options and with the use of the norm-conserved pseudopotentials Ceperley-Alder, simulate the sistems;
Publicado em: 2007
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9. Caracterização energética e estrutural da interação DNA-cisplatina pela teoria do funcional da densidade
Estudo do sistema DNA-cisplatina usando a teoria do funcional da densidade (DFT) compara a eficiência dos funcionais de correlação e troca LDA e GGA(PBE) na simulação das bases nitrogenadas como também os conjuntos de base DZP e DZ. Fazendo as opções DZP e LDA e com a utilização de pseudopotenciais Ceperley-Alder de norma conservada executa cálcul
Publicado em: 2007
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10. Espalhamento Raman de Sistemas a Base de GaN Dopados
In this work we present calculations of eletronic Raman cross-sections of doped GaN based system via charge - density mechanism. The studied structures were -doped superlattices and uniform doped GaN systems. In the case of periodically doped superlattice the eletronic structure was obtained using Density Funcional Theory in the local density approximation.
Publicado em: 2007
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11. Fotoionização de atomos relativisticos / Photoionization of relativistic atoms
In this work we present photoionization results for the valence s-electrons of Sodium, Potassium, Rubidium and Cesium atoms including relativistic effects. In our calculations we consider the photoionization of a non-polarized atom by linearly polarized light, using half occupation transition states, within the electric dipole approximation and the Local Den
Publicado em: 2007
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12. 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