Abstract
A semi-local kinetic energy density functional (KEDF) was constructed based on machine learning (ML). The present scheme adopts electron densities and their gradients up to third-order as the explanatory variables for ML and the Kohn-Sham (KS) kinetic energy density as the response variable in atoms and molecules. Numerical assessments of the present scheme were performed in atomic and molecular systems, including first- and second-period elements. The results of 37 conventional KEDFs with explicit formulae were also compared with those of the ML KEDF with an implicit formula. The inclusion of the higher order gradients reduces the deviation of the total kinetic energies from the KS calculations in a stepwise manner. Furthermore, our scheme with the third-order gradient resulted in the closest kinetic energies to the KS calculations out of the presented functionals.
Original language | English |
---|---|
Article number | 241705 |
Journal | Journal of Chemical Physics |
Volume | 148 |
Issue number | 24 |
DOIs | |
Publication status | Published - 2018 Jun 28 |
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry