Hi, I don't see a problem, I think you misinterpret what the numbers should be? The values are the sum of atomic vdW radii. Please see discussion in Grimme paper ~ Eq. 12. So it looks correct, no?
Thanks. / Nick Den fre. 15. dec. 2023 kl. 22.00 skrev Reza Behjatmanesh-Ardakani < [email protected]>: > Hi > I used "Grimme" code in the "Utils" directory to see the Grimme > parameters. I got the following results for a molecule on TiO2: > > ================= > MM.UnitsDistance Ang # what this program prints out DO NOT CHANGE > MM.UnitsEnergy eV # what this program prints out DO NOT CHANGE > MM.Grimme.S6 0.75 # Grimme-paper for PBE (correct for your functional) > MM.Grimme.D 20. # Grimme-paper (correct for your functional) > %block MM.Potentials > * 1 1 Grimme 111.94 3.124 # Ti, 10.1002/jcc.20495* > 1 2 Grimme 28.50 2.904 # Ti / O > 1 3 Grimme 45.06 3.014 # Ti / C > 1 4 Grimme 76.69 3.201 # Ti / Cl > 1 5 Grimme 12.74 2.563 # Ti / H > * 2 2 Grimme 7.26 2.684 # O, 10.1002/jcc.20495* > 2 3 Grimme 11.47 2.794 # O / C > 2 4 Grimme 19.53 2.981 # O / Cl > 2 5 Grimme 3.24 2.343 # O / H > 3 3 Grimme 18.14 2.904 # C, 10.1002/jcc.20495 > 3 4 Grimme 30.87 3.091 # C / Cl > 3 5 Grimme 5.13 2.453 # C / H > 4 4 Grimme 52.55 3.278 # Cl, 10.1002/jcc.20495 > 4 5 Grimme 8.73 2.640 # Cl / H > 5 5 Grimme 1.45 2.002 # H, 10.1002/jcc.20495 > %endblock MM.Potentials > ============================== > > I checked the reference of DOI: 10.1002/jcc.20495 for O and Ti atoms. > > I found that the R0 for the O atom is 1.324 A in the paper, but the above > code shows 2.684 A. > For the Ti atom, the paper shows 1.562 A, while the code shows 3.124 A. > I supposed that these R0 data are in Bohr, and convert them to Angstrom: > for O: 1.42 A > for Ti: 1.65 A > which again both are incorrect. > > Please correct the Grimme code in Utils. > > Thanks > > With the Best Regards > *Reza * > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence > (https://urldefense.com/v3/__http://www.max-centre.eu/__;!!D9dNQwwGXtA!S9P09VHly-w_rxj2KobbEaEaJ3xhfhmVwA2_p1DWgWYlBnLObDbJLYtMVPAEGTgFtvUJjfrOLOHmzJHyjQ$ > ) > -- Kind regards Nick
-- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
