Pathways of bond topology transitions at the interface of silicon nanocrystals and amorphous silica matrix

The interface chemistry of silicon nanocrystals (NCs) embedded in amorphous oxide matrix is studied through molecular dynamics simulations with the chemical environment described by the reactive force field model. Our results indicate that the Si NC-oxide interface is more involved than the previous...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2008-04
Main Authors: Yılmaz, D E, Bulutay, C, Çağın, T
Format: Article
Language:English
Subjects:
Abundance
Charge distribution
Computer simulation
Molecular dynamics
Nanocrystals
Organic chemistry
Oxidation
Oxygen
Silicon dioxide
Tensile strain
Topology
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The interface chemistry of silicon nanocrystals (NCs) embedded in amorphous oxide matrix is studied through molecular dynamics simulations with the chemical environment described by the reactive force field model. Our results indicate that the Si NC-oxide interface is more involved than the previously proposed schemes which were based on solely simple bridge or double bonds. We identify different types of three-coordinated oxygen complexes, previously not noted. The abundance and the charge distribution of each oxygen complex is determined as a function of the NC size as well as the transitions among them. The oxidation at the surface of NC induces tensile strain to Si-Si bonds which become significant only around the interface, while the inner core remains unstrained. Unlike many earlier reports on the interface structure, we do not observe any double bonds. Furthermore, our simulations and analysis reveal that the interface bond topology evolves among different oxygen bridges through these three-coordinated oxygen complexes.
ISSN:2331-8422
DOI:10.48550/arxiv.0804.2322