Thanks Giovanni for your quick answer.
Still, it's not clear to me how to set the starting magnetization.
Putting just starting_magnetization=X will be useless because this will
set a starting magnetization in all Si atoms, that will break no
symmetry.
On the other hand, if I understood well I can define two atomic species,
say Si1 and Si2, and define the starting magnetization for only one of
the two. I think that this is the thing I should do, but I can not
figure out which atoms should belong to one group or the other and
wheather I need more than two groups for this specific problem.
I was hoping to get help from someone who had already done similar
simulations.
Cheers
Le 2025-04-19 17:25, Giovanni Cantele a écrit :
Dear Lorenzo,
the variable starting_magnetization is usually used to drive the
system
out of the non magnetic solution, in that starting_magnetization(i) =
0 for all atomic species
should always bring to a spin unpolarized system. The starting value
in some cases is not so important
(different values will produce the same magnetic ground state), but as
far as I remember it could be
in some (not so frequent) cases where different magnetic energy minima
exist.
For the other questions:
- no special attention paid to the pseudopotential choice, if you mean
to choose a pseudopotential "specific"
for a spin-polarized calculation
- I would not use the input_DFT variable unless you need it for
specific purposes (e.g. non local functionals, like vdw-DF).
Ciao,
Giovanni
--
Giovanni Cantele, PhD
CNR-SPIN
c/o Dipartimento di Fisica
Universita' di Napoli "Federico II"
Complesso Universitario M. S. Angelo - Ed. 6
Via Cintia, I-80126, Napoli, Italy
e-mail: [email protected]
Phone: +39 081 676910
Skype contact: giocan74
ResearcherID: http://www.researcherid.com/rid/A-1951-2009
Web page: https://sites.google.com/view/giovanni-cantele/home
Il giorno sab 19 apr 2025 alle ore 16:37 Lorenzo Sponza
<[email protected]> ha scritto:
Dear Quantum ESPRESSO users and developpers,
I need some help to set up a calculation of a Si(111) 1x1 surface.
This
surface is characterized by dangling bonds that spoil the electronic
states around Fermi. In literature, two approaches are usually
adopted.
One consists in saturating the surface with H atoms, the other
consists
in performing a spin polarized calculation.
I want to give both methods a try, but I stuck when it comes to set
up
the spin polarized input file. I set nspin=2, but I'm perplexed
about
the value to give to starting_magnetization since I have only Si
atoms
here, and in this specific case it is not clear to me how this
variable
is interpreted and used by the code.
Finally, is there any attention to be paid in choosing the
pseudopotential or in specifying the input_DFT variable? I've used
PBE
scalar relativistic PAW pseudos so far.
Many thanks for your help.
--
Dr. Lorenzo Sponza
Chargé de Recherche au CNRS
Université Paris-Saclay, ONERA, CNRS Laboratoire d'étude des
microstructures (LEM)
29 Avenue de la division Leclerc, 92322 Châtillon
Tel: +33146734464
ETSF Research Team Leader
European Theoretical Spectroscopy Facility
17 Sart-Tilman B-4000 Liège, Belgium
_______________________________________________________________________________
The Quantum ESPRESSO Foundation stands in solidarity with all
civilians worldwide who are victims of terrorism, military
aggression, and indiscriminate warfare.
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_______________________________________________________________________________
The Quantum ESPRESSO Foundation stands in solidarity with all
civilians worldwide who are victims of terrorism, military aggression,
and indiscriminate warfare.
--------------------------------------------------------------------------------
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
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--
Dr. Lorenzo Sponza
Chargé de Recherche au CNRS
Université Paris-Saclay, ONERA, CNRS Laboratoire d'étude des
microstructures (LEM)
29 Avenue de la division Leclerc, 92322 Châtillon
Tel: +33146734464
ETSF Research Team Leader
European Theoretical Spectroscopy Facility
17 Sart-Tilman B-4000 Liège, Belgium
_______________________________________________________________________________
The Quantum ESPRESSO Foundation stands in solidarity with all civilians
worldwide who are victims of terrorism, military aggression, and indiscriminate
warfare.
--------------------------------------------------------------------------------
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
