|About this Abstract
||Materials Science & Technology 2009
||Characterization and Modeling of Ceramic-Ceramic and Metal-Ceramic Interfaces
||Characterization of Embedded Interfaces between Silicon Nanocrystals and Amorphous Silica Using Variable Charge Molecular Dynamics Simulations
||Flyura Djurabekova, Bryce Devine, Kai Nordlund, S B Sinnott
|On-Site Speaker (Planned)
Si nanocrystals embedded in amorphous silica exhibit interesting optical properties, such as photoluminescence, which depend on nanocrystal size. It is hypothesized that the optical properties arise from under-coordinated defect sites at the interface. However, the structure of the defect sites and their influence on optical properties are yet to be determined. In this effort, the interfacial structure of various sized nanocrystals embedded in amorphous silica were characterized by molecular dynamics simulations. The structures were first created using a non-ionic, bond-order potential. The final structures were then determined using a recently developed charge optimized many bodied potential. The oxide near the interface was found to be composed of a band of suboxide material. The actual bonded region of the interface varies from semi-coherent to under-coordinated defective regions, the proportions of which vary with crystal size. This study highlights our progress in variable charge potential development and their tremendous applicability to interfaces.