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arXiv · 1711.06529

Variational projector augmented-wave method: theoretical analysis and preliminary numerical results

Xavier Blanc·Eric Cancès·Mi-Song Dupuy
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Abstract

In Kohn-Sham electronic structure computations, wave functions have singularities at nuclear positions. Because of these singularities, plane-wave expansions give a poor approximation of the eigenfunctions. In conjunction with the use of pseudo-potentials, the PAW (projector augmented-wave) method circumvents this issue by replacing the original eigenvalue problem by a new one with the same eigenvalues but smoother eigenvectors. Here a slightly different method, called VPAW (variational PAW), is proposed and analyzed. This new method allows for a better convergence with respect to the number of plane-waves. Some numerical tests on an idealized case corroborate this efficiency.

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Xavier Blanc, Eric Cancès, Mi-Song Dupuy. 2017-11-17. Variational projector augmented-wave method: theoretical analysis and preliminary numerical results. https://doi.org/10.1016/j.crma.2017.05.004

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