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Title: Machine Learning a Universal Harmonic Interatomic Potential for Predicting Phonons in Crystalline Solids
Phonons, as quantized vibrational modes in crystalline materials, play a crucial role in determining a wide range of physical properties, such as thermal and electrical conductivity, making their study a cornerstone in materials science. In this study, we present a simple yet effective strategy for deep learning harmonic phonons in crystalline solids by leveraging existing phonon databases and state-of-the-art machine learning techniques. The key of our method lies in transforming existing phonon datasets, primarily represented in interatomic force constants, into a force-displacement representation suitable for training machine learning universal interatomic potentials. By applying our approach to one of the largest phonon databases publicly available, we demonstrate that the resultant machine learning universal harmonic interatomic potential not only accurately predicts full harmonic phonon spectra but also calculates key thermodynamic properties with remarkable precision. Furthermore, the restriction to a harmonic potential energy surface in our model provides a way of assessing uncertainty in machine learning predictions of vibrational properties, essential for guiding further improvements and applications in materials science.  more » « less
Award ID(s):
2317008
NSF-PAR ID:
10534580
Author(s) / Creator(s):
;
Editor(s):
Grein, Christoph
Publisher / Repository:
American Institute of Physics (AIP)
Date Published:
Journal Name:
Applied physics letters
Volume:
124
Issue:
10
ISSN:
0003-6951
Page Range / eLocation ID:
102202-1-6
Subject(s) / Keyword(s):
Vibrational properties, Potential energy surfaces, Electrical conductivity, Phonons, Thermodynamic properties, Deep learning, Machine learning, Crystalline solids, Interatomic force constants, Interatomic potentials
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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