Infrared and density-functional-theory study of spherosiloxane-based modelsilicon/silicon oxide interfaces - art. no. 155317

Nonlocal density functional theory (NL-DFT) (B3-LYP, 6-31 G**) has been emp loyed to calculate infrared frequencies and intensities for five structural models of H8Si8O12 on Si(100)-2x1. These calculations are compared to expe rimental results from reflection-absorption infrared spectroscopy (RAIRS). Three single-vertex models have been examined where -SiH3, -Si2H5, and a ni ne-atom silicon slab have been used to model the silicon surface. Two doubl e-vertex models have also been studied which represent a cluster bridging t wo dimer rows and an edge-activated cluster across a dimer row, respectivel y. This RAIRS/NL-DFT investigation supports a single-vertex. bonding model for H8Si8O12 chemisorbed to Si(100)-2x1. This structure implies a radical-b ased mechanism for the reaction at the surface.