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arXiv · 2305.11006

Prediction of NMR, X-ray and M\"ossbauer experimental results for amorphous Li-Si alloys using a novel DFTB model

Francisco Fernandez·Manuel Otero·Ma. Belén Oviedo·Daniel E. Barraco·S. Alexis Paz·Ezequiel P. M. Leiva
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Abstract

Silicon anodes hold great promise for next-generation Li-ion batteries. The main obstacle to exploiting their high performance is the challenge of linking experimental observations to atomic structures due to the amorphous nature of Li-Si alloys. We unveil the atomistic-scale structures of amorphous Li-Si using our recently developed density functional tight-binding model. Our claim is supported by the successful reproduction of experimental X-ray pair distribution functions, NMR and M\"ossbauer spectra using simple nearest neighbors models. The predicted structures are publicly available.

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Francisco Fernandez, Manuel Otero, Ma. Belén Oviedo, Daniel E. Barraco, S. Alexis Paz, Ezequiel P. M. Leiva. 2023-05-18. Prediction of NMR, X-ray and M\"ossbauer experimental results for amorphous Li-Si alloys using a novel DFTB model. https://arxiv.org/abs/2305.11006

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