001     21585
005     20221109161712.0
037 _ _ |a PreJuSER-21585
100 1 _ |0 P:(DE-Juel1)144723
|a Di Napoli, E.
|b 0
|u FZJ
111 2 _ |c Argonne, USA
|d 2012-04-05
245 _ _ |a Eigenproblems and Eigensolvers in Density Functional Theory
260 _ _ |c 2012
295 1 0 |a Seminar at Argonne Leadership Computing Facility
336 7 _ |a Talk (non conference)
|0 PUB:(DE-HGF)31
|2 PUB:(DE-HGF)
|x Invited
336 7 _ |a Conference Paper
|0 33
|2 EndNote
336 7 _ |a Other
|2 DataCite
336 7 _ |a Other
|2 DINI
336 7 _ |a INPROCEEDINGS
|2 BibTeX
336 7 _ |a LECTURE_SPEECH
|2 ORCID
500 _ _ |a Record converted from VDB: 12.11.2012
500 _ _ |3 Talk (non conference)
520 _ _ |a In DFT based simulations each SCF cycle comprises dozens of large generalized eigenproblems. In a recent study, it has been proposed to consider simulations as made of dozens of sequences of eigenvalue problems, where each sequence groups together eigenproblems with equal k-vector and increasing iteration index i. It was then demonstrated that successive eigenproblems in a sequence are strongly correlated to one another. In particular, by tracking the evolution over iterations of the angle between eigenvectors of adjacent iterations, it was shown the angles decrease noticeably after the first few iterations and become close to collinear. This last result suggests we could use the eigenvectors solution of a problem in a sequence as an educated guess for the eigenvectors of the successive problem. In this talk we present preliminary results that would eventually open the way to a widespread use of iterative solvers in ab initio electronic structure codes. We provide numerical examples where opportunely selected iterative solvers benefit from the reuse of eigenvectors when applied to sequences of eigenproblems extracted from simulations of real-world materials.
536 _ _ |0 G:(DE-Juel1)FUEK411
|2 G:(DE-HGF)
|a Scientific Computing
|c P41
|x 0
536 _ _ |a Simulation and Data Laboratory Quantum Materials (SDLQM) (SDLQM)
|0 G:(DE-Juel1)SDLQM
|c SDLQM
|f Simulation and Data Laboratory Quantum Materials (SDLQM)
|x 2
909 C O |o oai:juser.fz-juelich.de:21585
|p VDB
913 1 _ |0 G:(DE-Juel1)FUEK411
|1 G:(DE-HGF)POF2-410
|2 G:(DE-HGF)POF2-400
|b Schlüsseltechnologien
|k P41
|l Supercomputing
|v Scientific Computing
|x 0
914 1 _ |y 2012
920 1 _ |0 I:(DE-Juel1)JSC-20090406
|g JSC
|k JSC
|l Jülich Supercomputing Centre
|x 0
970 _ _ |a VDB:(DE-Juel1)137602
980 _ _ |a VDB
980 _ _ |a ConvertedRecord
980 _ _ |a talk
980 _ _ |a I:(DE-Juel1)JSC-20090406
980 _ _ |a UNRESTRICTED


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