About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
GPR-Assisted Ab-initio Approach for Identifying Transition States in Dynamically Stabilized, Structurally Unstable Phases |
Author(s) |
Seyyedfaridoddin Fattahpour, Sara Kadkhodaei |
On-Site Speaker (Planned) |
Seyyedfaridoddin Fattahpour |
Abstract Scope |
Saddle point search schemes are essential tools for identifying the transition state of material
processes, such as bulk or surface diffusion and surface adsorption. Typically, they explore the energy landscape in search of saddle points, if the initial and final states of the process correspond to basins on the energy surface. However, this assumption becomes invalid for solids exhibiting low-temperature phonon instability. We present a novel methodology that leverages GPR to develop a surrogate model for an effective temperature-dependent energy surface (TDES). By integrating the dimer method with GPR in an iterative feedback loop, we simultaneously sample the TDES and move towards the saddle point. Our methodology, named TD-GPR-dimer, studies diffusion processes in solids with low-temperature lattice instability, providing an alternative to computationally intensive direct atomistic simulation of diffusive hops. We demonstrate the application of TD-GPR-dimer on mechanically unstable but dynamically stabilized phases including bcc zirconium and cubic zirconia. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Other |