Nucleating a Different Coordination in a Crystal under Pressure: A Study of the B 1 -B 2 Transition in NaCl by Metadynamics
Here we propose an N P T metadynamics simulation scheme for pressure-induced structural phase transitions, using coordination number and volume as collective variables, and apply it to the reconstructive structural transformation B 1 -B 2 in NaCl. By studying systems with size up to 64 000 atoms we reach a regime beyond collective mechanism and observe transformations proceeding via nucleation and growth. We also reveal the crossover of the transition mechanism from Buerger-like for smaller systems to Watanabe-Tolédano for larger ones. The scheme is likely to be applicable to a broader class of pressure-induced structural transitions, allowing study of complex nucleation effects and bringing simulations closer to realistic conditions.
Physical Review Letters
- Pub Date:
- September 2021
- Condensed Matter - Materials Science;
- Condensed Matter - Statistical Mechanics
- 7 pages and 5 figures. For the Supplemental Material, please look into the source .zip archive