Neural Networks Accelerate the Ab Initio Prediction of Solid-Solid Phase Transitions at High Pressures
The Journal of Physical Chemistry Letters
|December 14, 2020
Summary
We developed a fast AI method to predict crystal structures and phase transitions, matching high-accuracy calculations but hundreds of times quicker. This accelerates research on high-pressure molecular crystals.
Area of Science:
- Computational chemistry
- Materials science
- Solid-state physics
Background:
- High-accuracy ab initio calculations like Møller-Plesset perturbation (MP2) are crucial for understanding material properties.
- However, the high computational cost of these methods limits their application to large systems, such as macromolecules.
Purpose of the Study:
- To develop an efficient computational approach for predicting Gibbs free energy, structural characteristics, and phase transitions in solid crystal structures.
- To overcome the limitations of traditional high-accuracy computational methods for large-scale systems.
Main Methods:
- A novel approach combining neural networks and the fragment method was developed.
- This method predicts thermodynamic and structural properties of solid crystals.
Main Results:
- The proposed method achieves prediction accuracy comparable to MP2 calculations.
- It is hundreds of times faster than MP2, significantly reducing computational cost.
- Predicted structures and phase transitions for ice phases IX and XV under extreme conditions showed excellent agreement with MP2 calculations and experimental data.
Conclusions:
- The developed approach accurately and efficiently predicts high-pressure structures and phase diagrams of solid systems.
- It effectively addresses the challenge of high computational cost in high-precision theoretical studies of high-pressure molecular crystals.
- This method has potential applications in materials science and condensed matter physics.
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