Dynamical brittle fractures of nanocrystalline silicon using large-scale electronic structure calculations

TL;DR

This paper introduces a hybrid large-scale electronic structure simulation method to study dynamical brittle fractures in nanocrystalline silicon, revealing anisotropic fracture propagation and surface reconstructions.

Contribution

The study develops a new hybrid computational scheme enabling large-scale electronic structure simulations of fracture processes in nanocrystalline silicon.

Findings

Fracture propagates anisotropically on the (001) plane.

Reconstructed surfaces with asymmetric dimers are observed.

Step structures emerge in larger systems indicating nanoscale to macroscale crossover.

Abstract

A hybrid scheme between large-scale electronic structure calculations is developed and applied to nanocrystalline silicon with more than 10$^5$ atoms. Dynamical fracture processes are simulated under external loads in the [001] direction. We shows that the fracture propagates anisotropically on the (001) plane and reconstructed surfaces appear with asymmetric dimers. Step structures are formed in larger systems, which is understood as the beginning of a crossover between nanoscale and macroscale samples.