CRYSTALLINE CLUSTER MODEL FOR IONIC SOLIDS - NACL

2083415342

Cross section and asymmetry parameter calculations for the C 1s photoionization of CH4, CF4, and CCl4

We have computed cross sections and asymmetry parameters for the C 1s photoionization of CX4 (X=H, F, Cl) using the Schwinger variational method with Pade corrections. We present a comparative study that shows the influence of the identity of the X atom on the computed cross sections. Predicted cross sections are in good agreement with available photoionization and photoabsorption experimental data. We conclude that the presence of heavy outer atoms produces resonance structures in the photoionization cross sections and in the asymmetry parameters. We find a single nonvalence resonant state in the photoionization of CF4 and multiple resonances in CCl4 that have significant d-orbital character in the vicinity of the Cl atoms.68

Theoretical investigation of electron collisions with sulfur monoxide in the low- and intermediate-energy range

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We report a theoretical study on electron collisions with the sulfur monoxide radical. More specifically, differential, integral, and momentum-transfer cross sections are calculated and reported in the 1-500 eV energy range. Calculations are performed at the static-exchange-polarization-absorption level of approximation. A combination of the iterative Schwinger variational method and the distorted-wave approximation is used to solve the scattering equations. Our study reveals shape resonances in both the doublet and quartet spin-specific scattering channels. The occurrence of such resonances may enhance the spin-flip effects. In addition, the comparison of our calculated total absorption cross sections with existing experimental total ionization cross sections is encouraging.802Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Theoretical study on electron-free-radical scattering: An application to CF

In this work, a theoretical study on electron-CF collisions in the low- and intermediate-energy range is reported. More specifically, calculated elastic differential, integral, and momentum-transfer cross sections as well as grand total (elastic and inelastic) and absorption cross sections are presented in the (1-500)-eV energy range. A complex optical potential is used to represent the electron-molecule interaction dynamics, while the Schwinger variational iterative method combined with the distorted-wave approximation is used to solve the scattering equations. Comparison of the present results with existing experimental and theoretical data for electron collisions with NO (an isoelectronic molecule of CF) is made.66

Cross sections for electron scattering by carbon disulfide in the low- and intermediate-energy range

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)In this work, we report a theoretical study on e(-)-CS(2) collisions in the low- and intermediate-energy ranges. Elastic differential, integral, and momentum-transfer cross sections, as well as grand total (elastic+inelastic) and absorption cross sections, are reported in the 1-1000 eV range. A recently proposed complex optical potential composed of static, exchange, and correlation-polarization plus absorption contributions is used to describe the electron-molecule interaction. The Schwinger variational iterative method combined with the distorted-wave approximation is applied to calculate the scattering amplitudes. The comparison between our calculated results and the existing experimental and/or theoretical results is encouraging.811Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Elastic and absorption cross sections for electron-nitrous oxide collisions

In this work, we present a joint theoretical-experimental study on electron-N2O collisions in the intermediate energy range. More specifically, calculated and measured elastic differential, integral, and momentum-transfer cross sections, as well as calculated total and absorption cross sections are reported. The measurements were performed using a crossed electron-beam-molecular-beam geometry. The angular distribution of the scattered electrons was converted to absolute cross sections using the relative-flow technique. Theoretically, a complex optical potential is used to represent the electron-molecule interaction dynamics in the present calculation. The Schwinger variational iterative method combined with the distorted-wave approximation is used to solve the scattering equations. The comparison of the present calculated results with the measured results as well as with the existing experimental and theoretical data shows good agreement.65

ELECTRON-IMPACT EXCITATION OF THE D(3)-PI-(U)(-)(V=0, 1, 2, 3 N=1) STATES OF H-2 - CROSS-SECTIONS AND ANISOTROPY PARAMETERS

52140441

Theoretical study on electron collisions with SiF and SiF(2) radicals in the low- and intermediate-energy range

A theoretical study on electron collisions with SiF and SiF(2) radicals in the low- and intermediate-energy range is reported. More specifically, calculated elastic differential, integral, and momentum transfer cross sections as well as total and total absorption cross sections are presented in the 1-1000-eV energy range. A complex optical potential is used to represent the electron-radical interaction dynamics, whereas the iterative Schwinger variational method combined with the distorted-wave approximation is used to solve the scattering equations. Comparison of the present results with the available theoretical and experimental results in the literature is made.76

Electron scattering by methanol and ethanol: A joint theoretical-experimental investigation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We present a joint theoretical-experimental study on electron scattering by methanol (CH3OH) and ethanol (C2H5OH) in a wide energy range. Experimental differential, integral and momentum-transfer cross sections for elastic electron scattering by ethanol are reported in the 100-1000 eV energy range. The experimental angular distributions of the energy-selected electrons are measured and converted to absolute cross sections using the relative flow technique. Moreover, elastic, total, and total absorption cross sections for both alcohols are calculated in the 1-500 eV energy range. A complex optical potential is used to represent the dynamics of the electron-alcohol interaction, whereas the scattering equations are solved iteratively using the Pade's approximant technique. Our calculated data agree well with those obtained using the Schwinger multichannel method at energies up to 20 eV. Discrepancies at high energies indicate the importance of absorption effects, included in our calculations. In general, the comparison between our theoretical and experimental results, as well as with other experimental data available in the literature, also show good agreement. Nevertheless, the discrepancy between the theoretical and experimental total cross sections at low incident energies suggests that the experimental cross sections measured using the transmission technique for polar targets should be reviewed. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3695211]13611Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

THEORETICAL-STUDY OF SINGLE VACANCIES IN GASB

105133934