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arXiv · 2503.05278

First-principles theory of ionic thermoelectricity

Byeoksong Lee·Joongoo Kang
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Abstract

Symmetry plays a crucial role in shaping the theories of fundamental forces. For example, general covariance -- the equivalence of all possible coordinate systems of spacetime -- dictates the law of gravity. Here, we extend this concept to nonequilibrium thermodynamics by developing a theory of ionic thermoelectricity (thermoelectricity without electrons) in electronically gapped ionic conductors. Within the Green-Kubo formalism, we show that energy gauge invariance -- the equivalence of all possible ways of distributing energy among atoms -- primarily determines the expressions for ionic thermoelectric coefficients. This symmetry-dictated theory is generally applicable, regardless of specific ion transport mechanisms, and provides a rigorous conceptual and computational framework for describing ionic thermoelectricity from first principles.

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Byeoksong Lee, Joongoo Kang. 2025-03-07. First-principles theory of ionic thermoelectricity. https://arxiv.org/abs/2503.05278

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