All-electron density functional theory and time-dependent density functional theory with high-order finite elements

Lauri Lehtovaara; Ville Havu; Martti Puska

doi:10.1063/1.3176508

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arXiv · 0902.2306

All-electron density functional theory and time-dependent density functional theory with high-order finite elements

Lauri Lehtovaara·Ville Havu·Martti Puska

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Abstract

We present for static density functional theory and time-dependent density functional theory calculations an all-electron method which employs high-order hierarchical finite element bases. Our mesh generation scheme, in which structured atomic meshes are merged to an unstructured molecular mesh, allows a highly nonuniform discretization of the space. Thus it is possible to represent the core and valence states using the same discretization scheme, i.e., no pseudopotentials or similar treatments are required. The nonuniform discretization also allows the use of large simulation cells, and therefore avoids any boundary effects.

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Lauri Lehtovaara, Ville Havu, Martti Puska. 2009-08-06. All-electron density functional theory and time-dependent density functional theory with high-order finite elements. https://doi.org/10.1063/1.3176508

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