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arXiv · 1610.03756

Lattice Dynamics Calculations based on Density-functional Perturbation Theory in Real Space

Honghui Shang·Christian Carbogno·Patrick Rinke·Matthias Scheffler
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Abstract

A real-space formalism for density-functional perturbation theory (DFPT) is derived and applied for the computation of harmonic vibrational properties in molecules and solids. The practical implementation using numeric atom-centered orbitals as basis functions is demonstrated exemplarily for the all-electron Fritz Haber Institute ab initio molecular simulations (FHI-aims) package. The convergence of the calculations with respect to numerical parameters is carefully investigated and a systematic comparison with finite-difference approaches is performed both for finite (molecules) and extended (periodic) systems. Finally, the scaling tests and scalability tests on massively parallel computer systems demonstrate the computational efficiency.

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Honghui Shang, Christian Carbogno, Patrick Rinke, Matthias Scheffler. 2016-10-12. Lattice Dynamics Calculations based on Density-functional Perturbation Theory in Real Space. https://doi.org/10.1016/j.cpc.2017.02.001

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