Reduced collinearity, low-dimensional cluster expansion model for adsorption of halides (Cl, Br) on Cu(100) surface using principal component analysis
Abstract
The cluster expansion model (CEM) provides a powerful computational framework for rapid estimation of configurational properties in disordered systems. However, the traditional CEM construction procedure is still plagued by two fundamental problems: (i) even when only a handful of site cluster types are included in the model, these clusters can be correlated and therefore they cannot independently predict the material property, and (ii) typically few tens-hundreds of datapoints are required for training the model. To address the first problem of collinearity, we apply the principal component analysis method for constructing a CEM. Such an approach is shown to result in a low-dimensional CEM that can be trained using a small DFT dataset. We use the ab initio thermodynamic modeling of Cl and Br adsorption on Cu(100) surface as an example to demonstrate these concepts. A key result is that a CEM containing 10 effective cluster interactions build with only 8 DFT energies (note, number of training configurations > number of principal components) is found to be accurate and the thermodynamic behavior obtained is consistent with experiments. This paves the way for construction of high-fidelity CEMs with sparse/limited DFT data.
- Publication:
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arXiv e-prints
- Pub Date:
- July 2023
- DOI:
- 10.48550/arXiv.2307.11698
- arXiv:
- arXiv:2307.11698
- Bibcode:
- 2023arXiv230711698D
- Keywords:
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- Condensed Matter - Disordered Systems and Neural Networks
- E-Print:
- 36 pages, 12 figures