Dear Giuseppe, Thank you! Best, Michal
On Fri, 3 Apr 2020 at 12:00, Giuseppe Mattioli <giuseppe.matti...@ism.cnr.it> wrote: > > > Dear Michal > I'm a fan of esm. If you want to study the adsorption of molecules > inducing a strong vertical dipole you are forced to decouple such > dipole along the z direction of the cell, otherwise you experiment an > horrible "capacitor effect" on the potential curve. To use esm='bc1' > (a vacuum-slab-vacuum geometry) you need to confine the electronic > density of your system (the density, not the atoms...) between -l/4 > and l/4 (you can shift the 0 of the cell if you don't want to shift > the atoms), where l is the z edge of your supercell. I don't know if > you consider this as an "enormous vacuum padding"... > > Moreover, esm produces "for free" a very useful file (in the TMP_DIR), > namely prefix.esm1, where at the end of each scf iteration useful > quantities are plotted, such as the electrostatic potential and the > charge density integrated on x,y planes. You may want to have a look > to this recent paper (J. Phys. Chem. C 2020, 124, 3601) to see what > you can do with such data (e.g., calculate changes in the surface > workfunction upon the adsorption of polar molecules). > > Finally, during the first scf iteration you may experiment a bit of > instability, but it is generally not a dramatic problem... > > HTH > Giuseppe > > > Quoting Michal Krompiec <michal.kromp...@gmail.com>: > > > Hello, > > I was wondering which assume_isolated method is the preferred choice > > for calculation of adsorption energies of small molecules on 2D slabs > > of metals and oxides. > > So far, I've been using assume_isolated='2d', but it requires an > > enormous vacuum padding. Is esm less resource-hungry? Does anyone use > > a less accurate scheme first (e.g. no "assume_isolated" and a small > > vacuum padding) and moves later to the target large cell with > > assume_isolated=2d? > > I understand that it all depends on the system, and that a convergence > > test has to be done anyway, but I would be grateful for any tips. > > > > Thanks, > > Michal Krompiec > > Merck KGaA > > _______________________________________________ > > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) > > users mailing list users@lists.quantum-espresso.org > > https://lists.quantum-espresso.org/mailman/listinfo/users > > > > GIUSEPPE MATTIOLI > CNR - ISTITUTO DI STRUTTURA DELLA MATERIA > Via Salaria Km 29,300 - C.P. 10 > I-00015 - Monterotondo Scalo (RM) > Mob (*preferred*) +39 373 7305625 > Tel + 39 06 90672342 - Fax +39 06 90672316 > E-mail: <giuseppe.matti...@ism.cnr.it> > > _______________________________________________ > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) > users mailing list users@lists.quantum-espresso.org > https://lists.quantum-espresso.org/mailman/listinfo/users _______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users