Adsorption of Li on Si(111) influenced by the phase transition (7x7)<->(1x1)

被引：6

作者：

Eckhardt, M ^{[1
]}

Chrost, J ^{[1
]}

Fick, D ^{[1
]}

机构：

[1] UNIV MARBURG,FACHBEREICH PHYS & WISSENSCH,ZENTRUM MAT WISSENSCH,D-35032 MARBURG,GERMANY

来源：

SURFACE SCIENCE | 1996年 / 366卷 / 02期

关键词：

alkali metals; chemisorption; nuclear magnetic resonance; semiconducting surfaces; silicon; surface thermodynamics;

D O I：

10.1016/0039-6028(96)00815-1

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The adsorption of Li on Si(111) (coverage below 10(-3) ML) was investigated around the (7x7) to (1x1) phase transition with nuclear magnetic resonance (NMR) and mean residence-time measurements. At the phase transition the local density of states at the Fermi energy drops significantly, indicating a transition from a ''metallic'' surface for the (7x7) reconstruction to a semiconducting surface for the (1x1) one. At the phase transition the activation energy for desorption changes from 2.5 to 2.85 eV. Furthermore, the electric field gradient at the adsorbed Li nucleus, which reflects the surrounding charge distribution, has a discontinuity at the phase transition.

引用

页码：275 / 284

页数：10