Atomic structure and rippling of amorphous two-dimensional SiC nanoribbons – MD simulations

Abstract

Atomic structure and rippling of the amorphous two-dimensional SiC nanoribbons (a-2D SiC NRs) are studied by means of molecular dynamics (MD) simulations. Amorphous models are obtained by cooling from the melt. Atomic structure of a-2D SiC NRs is analyzed in details. We find that atomic structure of glassy 2D SiC nanoribbons is disordered not only by containing various structural defects including rings of various sizes and shapes but also by the non-alternative distributions of Si and C atoms inside the rings. This structure is quite different from that of the crystalline counterparts although the 6-fold rings also dominate in the amorphous models. Moreover, size effects on rippling of a-2D SiC NRs are analyzed. On the other hand, wrinkled disordered atomic structure of amorphous 2D SiC NRs has a tendency to reduce the rippling amplitude compared to that of the crystalline counterparts. We find a significant amount of 5-fold rings occurred in the amorphous 2D SiC nanoribbons that are obtained by cooling from the melts. These 5-fold rings stabilize the glassy 2D structure.