Adsorption of fullerenes C-n (n=32,36,40,44,48,60) on the GaAs(001)-c(4x4) reconstructed surface

作者：Zhou CG^*; Wu JP; Han B; Yao SJ; Cheng HS

来源：Physical Review B, 2006, 73(19): 195324.

DOI：10.1103/PhysRevB.73.195324

We present first principles studies using density functional theory on adsorption of fullerene molecules C-n (n=32,36,40,44,48,60) on the c(4x4) reconstructed GaAs(001) surface. Adsorption at various surface sites coupled with numerous fullerene orientations were systematically sampled to obtain energetically most stable structures. With the orientation of a fullerene with one of the hexagons facing down the substrate, the surface trenches were identified as the sites that give the strongest adsorption. The orientational preference for C-32 adsorption is an exception due to its unique stability in its electronic structure. It was found that the As atoms with a dangling bond in the second surface layer play a most critical role in determining the adsorption structure and strength, while the top layer As dimers are only capable of forming weak bonding with fullerenes, which differs significantly from adsorption of fullerenes and small unsaturated organic molecules on silicon surfaces. Strong covalent bonds between fullerenes and the substrate are formed and considerable deformation of fullerenes near the adsorption sites is observed. The calculated adsorption energy decreases as the size of fullerenes increases. The calculation yields useful physical insight into the adsorption mechanism and the physicochemical properties of the materials.

• 出版日期2006-5
• 单位中国地质大学（北京）