Second generation Car-Parrinello MD: application to the h-BN/Rh(111) nanomesh

摘要

Hexagonal boron nitride sp(2) layers grown and supported on the Rh(111) metal surface attracted quite some interest thanks to the structural and electronic peculiarities of this quasi-2D system. The honeycomb regular corrugation is the key feature at the origin of several properties and applications in nanotechnology, e.g., the selective adsorption and functionalisation related to the modulation of the electronic structure. Atomistic simulations play an important role, since they can shed light on the nature of such a complex interface, providing resolution of details that cannot be achieved experimentally. However, the studies by electronic structure calculations have been mostly limited to static models of the optimized system. The sampling of configurations at finite temperature by ab-initio molecular dynamics requires significantly larger computational effort, and can become unfeasible for large scale and metallic models, as it is the case of h-BN/Rh(111). In this work, we employ a recently developed Car-Parrinello-like approach to overcome the performance limitations of the standard Born-Oppenheimer molecular dynamics scheme, thus obtaining a speed-up of 17x. We report on the set-up and the application of this approach to simulate the h-BN/Rh(111) interface at different temperatures and discuss the thermal stability of the corrugated pattern.