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Machine learning potentials (MLPs) for atomistic simulations have an enormous prospective impact on materials modeling, offering orders of magnitude speedup over density functional theory (DFT) calculations without appreciably sacrificing accuracy in the prediction of material properties. However, the generation of large datasets needed for training MLPs is daunting. Herein, we show that MLP-based material property predictions converge faster with respect to precision for Brillouin zone integrations than DFT-based property predictions. We demonstrate that this phenomenon is robust across material properties for different metallic systems. Further, we provide statistical error metrics to accurately determine a priori the precision level required of DFT training datasets for MLPs to ensure accelerated convergence of material property predictions, thus significantly reducing the computational expense of MLP development.
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Advancing the design of gold nanomaterials with machine-learned potentials
Abstract Gold nanoparticles (NPs), and their smaller (< 2 nm) counterpart, known as gold nanoclusters (NCs), have emerged in recent years as highly efficient catalysts. They exhibit unique properties, are highly tailorable, and are highly promising for applications in nanomedicine, sensing, and bioimaging. The design of nanomaterials with optimal properties hinges on our ability to understand and control their structure-function relationship, which has remained a challenge so far. The dual organic-metallic nature of ligand-protected Au NCs complicates the experimental characterization of their structure. Density Functional Theory (DFT) calculations are highly accurate but have a high computational cost, making such calculations on large NPs and over long simulation times beyond our reach. Classical simulations allow for a thorough exploration of the configuration space but the empirical force fields they rely on often lack accuracy. In this Topical Review, we discuss recent advances enabled by Machine-Learned Potentials (MLPs), which have the ability to predict energies and atomic forces with DFT-like accuracy for a fraction of the computational cost and can be readily used in molecular simulations. We further show how MLPs have led to the elucidation of the structure, stability, thermodynamics, and reactivity of nanomaterials, thereby paving the way for the accelerated computationally-guided design of Au nanomaterials.
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- Award ID(s):
- 2247574
- PAR ID:
- 10591639
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Nano Express
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2632-959X
- Format(s):
- Medium: X Size: Article No. 022001
- Size(s):
- Article No. 022001
- Sponsoring Org:
- National Science Foundation
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