Figure 7
From: Silicon and Germanium Nanostructures for Photovoltaic Applications: Ab-Initio Results
Kohn–Sham orbitals at 10% of their maximum amplitude for the Si32 (top), Ge16Si16 (center), and Ge32 (bottom) crystalline embedded NCs. The LUMO state is represented in dark red (black), the HOMO state is represented in blue (gray), the HOMO-1 in azure (light gray), and the HOMO-2 in lightest blue (lightest gray). The Si and Ge atoms of the NC are shown in yellow (light gray) and green (gray) thick sticks, respectively. For a better visibility of the images the SiO2 atoms surrounding the NCs are not shown (color online)