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Journal articles
Ab initio calculations of electronic excitations: Collapsing spectral sums
Abstract : We present a method for the evaluation of electronic excitations of advanced materials by reformulating spectral sum-over-states expressions such that only occupied states appear. All empty states are accounted for by one effective energy. Thus we keep the simplicity and precision of the sum-over-states approach while speeding up calculations by more than an order of magnitude. We demonstrate its power by applying it to the GW method, where a huge summation over empty states appears twice (screening and self-energy). The precision is shown for bulk Si and solid and atomic Ar. We then use it to determine the band gap of the technologically important oxide SnO2.
https://hal-polytechnique.archives-ouvertes.fr/hal-00562657
Contributor : Gaëlle Bruant Connect in order to contact the contributor
Submitted on : Thursday, February 3, 2011 - 5:13:12 PM
Last modification on : Thursday, September 30, 2021 - 9:02:02 PM
Contributor : Gaëlle Bruant Connect in order to contact the contributor
Submitted on : Thursday, February 3, 2011 - 5:13:12 PM
Last modification on : Thursday, September 30, 2021 - 9:02:02 PM