Matrix Structure Exploitation in Generalized Eigenproblems Arising in Density Functional Theory

Edoardo Di Napoli; Paolo Bientinesi

doi:10.1063/1.3498648

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arXiv · 1007.4400

Matrix Structure Exploitation in Generalized Eigenproblems Arising in Density Functional Theory

Edoardo Di Napoli·Paolo Bientinesi

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Abstract

In this short paper, the authors report a new computational approach in the context of Density Functional Theory (DFT). It is shown how it is possible to speed up the self-consistent cycle (iteration) characterizing one of the most well-known DFT implementations: FLAPW. Generating the Hamiltonian and overlap matrices and solving the associated generalized eigenproblems $Ax = λBx$ constitute the two most time-consuming fractions of each iteration. Two promising directions, implementing the new methodology, are presented that will ultimately improve the performance of the generalized eigensolver and save computational time.

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Edoardo Di Napoli, Paolo Bientinesi. 2010-07-26. Matrix Structure Exploitation in Generalized Eigenproblems Arising in Density Functional Theory. https://doi.org/10.1063/1.3498648

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