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Dynamical Matrices and Interatomic-Force Constants from Wave-Commensurate Supercells

Hadley M. Lawler·Eric K. Chang·Eric L. Shirley
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Abstract

We apply standard, first-principles calculations to a complete treatment of lattice dynamics in the harmonic approximation. The algorithm makes use of the straightforward ``frozen-phonon'' approach to the calculation of vibrational spectra and addresses some limitations of the method. Our prescription's validity is independent of crystal structure. It treats polar crystals in a general way, and it incorporates interatomic-force constants reaching beyond the supercell that is considered. For a range of materials, phonon dispersion exhibits the close agreement with experiment that is now characteristic of first-principles schemes. Results for graphite, Si and GaAs are presented.

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Hadley M. Lawler, Eric K. Chang, Eric L. Shirley. 2004-07-13. Dynamical Matrices and Interatomic-Force Constants from Wave-Commensurate Supercells. https://arxiv.org/abs/cond-mat/0407221

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