INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Neutralization of Li+ions scattered by (100) and (111) Cu surfaces: a localized atom-atom interaction model.
Autor/es:
EVELINA A. GARCÍA; M. A. ROMERO; C. GONZÁLEZ; E. C. GOLDBERG
Lugar:
Puerto Iguazú
Reunión:
Simposio; XIX Latin American Symposium on Solid State Physics (SLAFES); 2008
Resumen:
<!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;
mso-font-charset:0;
mso-generic-font-family:roman;
mso-font-pitch:variable;
mso-font-signature:-1610611985 1107304683 0 0 159 0;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;
mso-font-charset:0;
mso-generic-font-family:swiss;
mso-font-pitch:variable;
mso-font-signature:-1610611985 1073750139 0 0 159 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{mso-style-unhide:no;
mso-style-qformat:yes;
mso-style-parent:"";
margin-top:0cm;
margin-right:0cm;
margin-bottom:10.0pt;
margin-left:0cm;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:Calibri;
mso-fareast-theme-font:minor-latin;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:"Times New Roman";
mso-bidi-theme-font:minor-bidi;
mso-ansi-language:ES-AR;
mso-fareast-language:EN-US;}
.MsoChpDefault
{mso-style-type:export-only;
mso-default-props:yes;
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:Calibri;
mso-fareast-theme-font:minor-latin;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:"Times New Roman";
mso-bidi-theme-font:minor-bidi;
mso-fareast-language:EN-US;}
.MsoPapDefault
{mso-style-type:export-only;
margin-bottom:10.0pt;
line-height:115%;}
@page Section1
{size:595.3pt 841.9pt;
margin:70.85pt 3.0cm 70.85pt 3.0cm;
mso-header-margin:35.4pt;
mso-footer-margin:35.4pt;
mso-paper-source:0;}
div.Section1
{page:Section1;}
-->
Large and face dependent
neutral fractions have been found recently in ion scattering experiments in Li+/Cu(100)
and Li+/Cu(111) systems. These results for surfaces with high work functions
are unexpected within the traditional
picture of a Li+ departing from a jellium surface model. In the present work
the Li+/Cu(100) and Li+/Cu(111) interacting systems are described by
apreviously developed bond-pair model based on the localized interactions
between the projectile ion and the atoms of the surface, and on the extended
features of the electronic band structure through the density matrix. By only
including the resonant neutralization to the Li atom ground state we explained
the face and energy dependences of the measured neutral fraction within the
range of large outgoing energy values. We found that the downward shift of the
Li ionization level below the Fermi level caused by the short range chemical
interactions, is the main responsible of a high neutralization by the resonant
mechanism. The remaining differences between theory and experiment at low
energy values and the calculated distance behavior of the energy levels suggest
that the first excited (Li-1s22p) and negative (Li-1s22s2) states cannot be
disregarded in the ion-surface charge exchange process, and neither the
presence of projected surface band gaps in the Cu(111) surface.