Theoretical Models for the Electronic Structure of Hydrogenated Amorphous Silicon II: Three-Center Bonds.

摘要

SCF-X alpha-SW molecular-orbital calculations have been carried out for several configurations of hydrogenated silicon clusters in order to determine the contribution of three-center bonding to the electronic structure of hydrogenated amorphous silicon. Three-center bonding of the dissociated molecular hydrogen is shown to stabilize Si-Si bonds over a wide range of Si-Si distances. It can be concluded that hydrogenation can, in principle, saturate all strained as well as dangling bonds in a-Si. The results further indicate that a single hydrogen three-center bond is unlikely in a-Si:H alloys.