[QE-users] Adhesion Work

[Giovanni Cantele]

Hi, I would say that you should divide by two, because you have two
interfaces per unit cell.

I'm just wondering what would happen for an "isolated" interface. In other
words, what you are considering is actually a
"superlattice" in that the A-B sequence is periodically repeated.
Consecutive replicas are separated by only 2-3 A distance.
How different would be the interface
energy you compute after adding a, let's say, 10 Ang vacuum (in this case
the interface energy should be computed without dividing by 2).
In other words, I would compare the interface energy as computed from the
A-B-A-B-A-B-..... superlattice [dividing by 2 as you said] with that
computed
from the A-B-10 Ang-A-B-10Ang-.....structure (10Ang = vacuum) [without
dividing by 2].

Giovanni
-- 

Prof. Giovanni Cantele
Dipartimento di Fisica "Ettore Pancini"
Universita' degli Studi di Napoli "Federico II"
Complesso Universitario M. S. Angelo - Ed. 6
Via Cintia, I-80126, Napoli, Italy
e-mail: giovanni.cantele at unina
Phone: +39 081 676910

Web page: https://sites.google.com/view/giovanni-cantele/home


Il giorno mar 21 ott 2025 alle ore 14:07 michele de angelis <
michele.deangelis.01 at alumni.uniroma2.eu> ha scritto:

> Dear all,
> I built a periodic supercell (no vacuum along z) with ASE, containing YBCO
> and STO slabs with identical terminations (and identical vaccum) on top and
> bottom (symmetric slabs) along (001) direction. Furthermore, the lattice
> parameter of the substrate (for the lattice mismatch) was imposed on the
> interface area. After relaxing the structure, I perform an scf calculation
> to determine the energy of the interface (all details on the calculation
> are in the attached file). I compute energies E_A (slab A, symmetric), E_B
> (slab B, symmetric), and E_AB (full supercell ). Now, I want to determine
> the adhesion work for this interface (with these terminations). If you look
> at the structure of the supercell, in the attached input file that
> dispatches the interface, you only see one interface. The cell therefore
> contains two equivalent interfaces (A|B and B|A) by PBC.
> My question:
> to report the adhesion work per unit area for a *single* interface, should
> I use:
> W = (E_A + E_B - E_AB) / (2*A)
> (i.e. divide by 2 because there are two equivalent interfaces in the
> cell)? or not?
> Thank you in advance for your support.
>  Best regards,
>
> Michele De Angelis
> PhD student, Dept. of Chemical Sciences and Technologies, Univesity of
> Rome Tor Vergata (Italy)
>
>
> _______________________________________________________________________________
> 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 users at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20251022/1509fa14/attachment.html>