Density-Based Basis-Set Incompleteness Correction for GW Methods

• DOI: 10.1021/acs.jctc.9b01067
• Publication Date: 2019-12-31T21:01:07Z
• Authors: Pierre-François Loos; Barthélémy Pradines; Anthony Scemama; Emmanuel Giner; Julien Toulouse
• Keywords: Electronic correlation; Thymine; Basis (linear algebra); Nucleobase; Basis function

Similar to other electron correlation methods, many-body perturbation theory methods based on Green's functions, such as the so-called GW approximation, suffer from usual slow convergence of energetic properties with respect size one-electron basis set. This displeasing feature is due lack explicit electron-electron terms modeling infamous Kato cusp and Coulomb hole around it. Here, we propose a computationally efficient density-based basis-set correction short-range density functionals which significantly speeds up energetics toward complete set limit. The performance this illustrated by computing ionization potentials 20 smallest atoms molecules GW100 test at perturbative (or G0W0) level using increasingly large sets. We also compute five canonical nucleobases (adenine, cytosine, thymine, guanine, uracil) show that, here again, significant improvement obtained.