Schwinger Multichannel Method
Mostrando 1-12 de 15 artigos, teses e dissertações.
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1. Interações entre glicina e elétrons de baixa energia: formação de íons metaestáveis e afinidade eletrônica / Interactions between glycine and low energy electrons: formation of metastable ions and electron affinity
In this work we have performed calculations of elastic differential and integral cross-sections for electron-glycine scattering , and performed calculations of electron affinities of gly-(H2O)n clusters. The scattering calculations were done using the Schwinger multichanel method with pseudopotentials (SMCPP) in the static-exchange (SE) and in the static-exc
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/12/2010
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2. Applications of the Schwinger multichannel method to electron and positron scattering by molecules / Aplicaçôes do metodo multicanal de Schwinger ao espalhamento de eletrons e positrons por moleculas
O Método Multicanal de Schwinger (SMC) foi utilizado para estudar o espalhamento de elétrons e pósitrons de baixa energia por moléculas de pirrol (C4H4NH) e propanol (C3H7OH), para o primeiro caso, e acetileno (C2H2) e monóxido de carbono (CO), para o último caso. Seções de choque elásticas integrais e diferenciais foram calculadas para todos os sis
Publicado em: 2010
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3. Low-energy electron collisions with ethane
We employed the Schwinger multichannel method to compute elastic cross sections for low-energy electron collisions with ethane (C2H6). The calculations were carried out in the static-exchange and static-exchange plus polarization approximations for energies up to 12 eV. Our integral cross section shows good agreement with experimental data and with theoretic
Brazilian Journal of Physics. Publicado em: 2009-03
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4. The improvement of the Schwinger multichannel method for positron-atom/molecule scattering / O aprimoramento do metodo multicanal de Schwinger para o espalhamento de positrons por atomos/moleculas
Neste trabalho são apresentadas três modificações realizadas no Método Multicanal de Schwinger (SMC) para o espalhamento de pósitrons por moléculas (átomos): a inclusão de um potencial complexo para simular a absorção de partículas, a inclusão de um potencial delta real, proveniente de correções relativísticas, e a exibilização da base com
Publicado em: 2008
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5. Polarização do alvo molecular no espalhamento de eletrons / Polarization of molecular target in electron scattering
The aim of this work is the inclusion of polarization effects in the calculations of scattering cross section by using model potentials. The implementation was made in the Schwinger multichannel method with pseudopotentials, using a description of polarization potential with gaussians functions. With this potential we entend to reduce the computational cost
Publicado em: 2007
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6. Electron collisons with cyclobutane
We report integral, differential, and momentum transfer cross sections for elastic scattering of low-energy electrons by cyclobutane (c-C4H8), which is an isomer of the C4H8 molecule and has a closed chain. Our calculations were performed with the Schwinger multichannel method with pseudopotentials at the static-exchange level of approximation, for energies
Brazilian Journal of Physics. Publicado em: 2006-06
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7. Vibrational excitations mediated by a electronic Feshbach resonance 2Eg+ in electron scattering by hydrogen molecules / Excitações vibracionais medidas pela ressonancia de Feshbach eletronica 2Eg+ no espalhamento de eletrons por moleculas de hidrogenio
The relationship between Feshbach resonances and electronic excitation is well known in electron scattering by Hydrogen molecules, but still little exploited in the positron scattering case, making interesting, a comparative study. However, before thinking about comparisons, we have to address the question if, in fact, a Feshbach resonance manifests itself i
Publicado em: 2006
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8. Electronic excitations by positron impact in Schwinger multichannel method / Excitações eletronicas por impacto de positrons via Metodo Schwinger multicanal
Nesta tese investigamos a modelagem teórica de colisões pósitron-molécula no regime de baixas energias utilizando o método Schwinger multicanal. Nosso objetivo inicial foi sofisticar o procedimento de cálculo do parâmetro de aniquilação¸ Zeff . Esta quantidade é diretamente proporcional a taxa de aniquilação de pósitrons com elétrons da nuvem
Publicado em: 2006
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9. Comparative study of vibracional excitation of hydrogen molecules by electron and positron impact / Estudo comparativo das seções de choque de excitações vibracionais de moleculas de hidrogenio por impacto de positrons e eletrons
Here we report a comparative calculation of both integral and differential vibrational excitation cross sections of low energy positron and electron scattering against Hydrogen molecules (H2). For these calculations we have used the Schwinger Multichannel (SMC) Method [1] for positron collision [2] and electron collision [3]. Using a set of SMC scattering am
Publicado em: 2006
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10. Applications of the Schwinger Multichannel method with pseudopotentials to electron scattering from polyatomic molecules II: rotational excitation cross sections
This paper reports results for rotational excitation of H2O and H2S molecules by electron impact. It is also a databasis including tables of previously published rotationally resolved cross sections for CH4, SiH4, GeH4, SnH4, PbH4, NH3, PH3, AsH3, SbH3, CF4, CCl4, SiCl4 SiBr4, and SiI4. Our scattering amplitudes were calculated using the Schwinger multichann
Brazilian Journal of Physics. Publicado em: 2001-03
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11. Applications of the Schwinger multichannel method with pseudopotentials to electron scattering from polyatomic molecules I: elastic cross sections
This paper is a data basis which includes tables of integral, differential, and momentum transfer cross sections for elastic electron scattering from CF4, CCl4, SiCl4, SiBr4, SiI4, CH3F CH2F2, CHF3, CH3Cl, CH2Cl2, CHCl3, CF3Cl, CF2Cl2, CFCl3, CH3Br, CH3I, SiH3Cl, SiH3Br, SiH3I, GeH3Cl, GeH3Br, SnH3Br, C2H6, Si2H6, Ge2H6, B2H6, Ga2H6, H2O, H2S, H2Se, H2Te, tr
Brazilian Journal of Physics. Publicado em: 2001-03
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12. Elastic scattering of low-energy electrons by carbon disulphide
We report results from an ab initio calculation of low-energy electron scattering by CS2 molecules using the Schwinger multichannel method with pseudopotentials. We calculated elastic integral, differential and momentum transfer cross sections in an energy range from 5 eV up to 50 eV and compared our results with available theoretical results and experimenta
Brazilian Journal of Physics. Publicado em: 2000-03