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Theory and applications of the stress density

Alessio Filippetti·Vincenzo Fiorentini
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Abstract

Drawing on the theory of quantum mechanical stress, we introduce the stress density in density functional theory. In analogy with the Chetty-Martin energy density, the stress density provides a spatial resolution of the contributions to the integrated macroscopic stress tensor. We give specific prescriptions for a practical and efficient implementation in the plane wave ultrasoft pseudopotential method within the local-density approximation. We demonstrate the abilities of the stress density studying a set of representative test cases from surface and interface physics. In perspective, the stress density emerges as vastly more powerful and predictive than the integrated macroscopic stress.

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Alessio Filippetti, Vincenzo Fiorentini. 1999-12-21. Theory and applications of the stress density. https://doi.org/10.1103/physrevb.61.8433

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