Diffusion and Coalescence of Phosphorene Monovacancies Studied Using High-Dimensional Neural Network Potentials

Author(s)
Lukas Kyvala, Andrea Angeletti, Cesare Franchini, Christoph Dellago
Abstract

The properties of two-dimensional materials are strongly affected by defects that are often present in considerable numbers. In this study, we investigate the diffusion and coalescence of monovacancies in phosphorene using molecular dynamics (MD) simulations accelerated by high-dimensional neural network potentials. Trained and validated with reference data obtained with density functional theory (DFT), such surrogate models provide the accuracy of DFT at a much lower cost, enabling simulations on time scales that far exceed those of first-principles MD. Our microsecond long simulations reveal that monovacancies are highly mobile and move predominantly in the zigzag rather than armchair direction, consistent with the energy barriers of the underlying hopping mechanisms. In further simulations, we find that monovacancies merge into energetically more stable and less mobile divacancies following different routes that may involve metastable intermediates.

Organisation(s)
Computational and Soft Matter Physics, Computational Materials Physics
External organisation(s)
University of Bologna
Journal
Journal of Physical Chemistry C
Volume
127
Pages
23743-23751
No. of pages
9
ISSN
1932-7447
DOI
https://doi.org/10.1021/acs.jpcc.3c05713
Publication date
12-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103043 Computational physics
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, General Energy, Surfaces, Coatings and Films, Physical and Theoretical Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/7738a30d-c290-486e-85b6-4828b79d6d9b