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Filtering a distribution simultaneously in real and Fourier space

Eduardo Anglada·Jose M. Soler
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Abstract

We present a method to filter a distribution so that it is confined within a sphere of given radius r_c and, simultaneously, whose Fourier transform is optimally confined within a sphere of radius k_c. Our procedure may have several applications in the field of electronic structure methods, like the generation of optimized pseudopotentials and localized pseudocore charge distributions. As an example, we describe a particular application within the SIESTA method for density functional calculations, in removing the spurious rippling of the energy surface generated by the integrations in a real space grid.

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Eduardo Anglada, Jose M. Soler. 2005-12-22. Filtering a distribution simultaneously in real and Fourier space. https://doi.org/10.1103/physrevb.73.115122

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