INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Negative hydrogen ion fraction in H+ scattering from a HOPG surface: graphite DOS effect
Autor/es:
F. BONETTO; E. A. GARCÍA; R. VIDAL; J. FERRON; E. C. GOLDBERG
Revista:
APPLIED SURFACE SCIENCE
Referencias:
Año: 2006
ISSN:
0169-4332
Resumen:
Ion scattering spectrometry with time of flight analysis is employed to measure the ion fraction of hydrogen positively charged (H+) projectiles scattered from a well characterized Highly Oriented Pyrolitc Graphite (HOPG) surface at a 45o scattering angle. The ion fraction is determined for 4 KeV and 5 KeV incident energies and various exit angles after analyzing the time of flight spectra. In the theoretical approach, the adsorbate-substrate interacting system is adequately described by means of an Anderson like Hamiltonian where the valence and core surface states are included. Under the previous assumption of a rapid neutralization of H+ projectiles (mainly related with a resonant electron capture), the negative ionization probability is calculated by employing a Green's function formalism to solve the dynamic collisional process. Both theoretical and experimental results are analyzed and contrasted, and the influence of the graphite local density of states is discussed.