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Updated: Jul 4, 2026

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Local and density fitting approximations within the short-range/long-range hybrid scheme: application to large
Erich Goll1, Thierry Leininger, Frederick R Manby
1Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569, Stuttgart, Germany. goll@theochem.uni-stuttgart.de
Abstract:
We introduce local and density fitting approximations into a hybrid approach which couples short-range density functionals with long-range wave-functions. The use of density fitting methods within the local-correlation approximation makes it possible to tackle bigger systems than without these methods, so that we are now able to treat systems of biological interest within the DFT/ab initio scheme. In first benchmark calculations, we apply it to the S22 database of Hobza and co-workers for binding energies of weakly bound molecular clusters.
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