Relation of the Si-H stretching frequency to the nanostructural Si-H bulk environment

摘要: We propose a model which describes the frequency shift $(\ensuremath{\Delta}{\ensuremath{\omega}}_{\mathit{SM}})$ of stretching mode (SM) $\mathrm{Si}\mathrm{H}$ monohydrides (MH's) when incorporated in hydrogenated amorphous silicon $(a\text{\ensuremath{-}}\mathrm{Si}:\mathrm{H})$ with respect to unscreened MH SM at $\ensuremath{\sim}2099\ifmmode\pm\else\textpm\fi{}2\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$. The is based on an effective medium approximation dielectric using multiple Lorentz-Lorenz dielectrics, corresponding host MH's embedded cavities, separately. $\ensuremath{\Delta}{\ensuremath{\omega}}_{\mathit{SM}}$ as derived this correctly predicts all bulk MH-SM positions $a\text{\ensuremath{-}}\mathrm{Si}:\mathrm{H}$ films and relates it directly nanostructure configurations.