Hi Pietro,
Thank you for taking the time to respond. This has been a very enlightening
discussion for me. I will try the Wannier code and see what I get.
Best wishes,
Vahid
On Apr 16, 2020, at 3:52 AM, Pietro Delugas
mailto:pdelu...@sissa.it>> wrote:
CAUTION: The Sender of this email is not
Hi Vahid
In principle all occupied bands could contribute to the big difference
between the dynamical charges and the oxydation numbers. How much they
contribute depends on their polarizability. And I agree with you that
following what I said about the behavior of the S-3p band, the Pb-6s
Hi Pietro,
If I understand your argument correctly, then the same can be said of the 2
electrons of s-Pb localized just above 0eV. These 2 electrons are mainly
centered on Pb, hybridized with other orbitals and move with Pb (in addition to
10 d-electrons). So the dynamical charge for Pb is ~
Hello
from the pdos 2 electrons have /moved /from Pb 6p to fill the S 3p
band, as expected.
The 3p band is hybridized with 6s and 6p orbitals of Pb and vice versa.
So the S 3p is still made by orbitals centered on S ions but is spread
to neighboring Pb ions. If a S ion is displaced it goes
Dear Stefano,
Thank you for this quick response. I was following Xavier Gonze’s argument in
PRB58, 6224 (1998) Eq. 20 where
Z*(u)=dp/du, where p is the dipole moment and u is the displacement. Since
p=u.Z(u), we get
Z*(u)=Z(u)+udZ(u)/du, where Z(u) is the static charge.
So here the Born
I didnt follow completely your argument about the Bader charge but what
one should keep in mind is that the effective charge is the change in
polarization due to displacement not the change in charge...
think of a core electron shell (as the d orbitals of Pb can
approximately be considered)
Dear QE Community,
I have calculated the Born charges using the PHONON code for PbS. The only
non-zero elements are the diagonal ones and are 4.122 and -4.168, respectively.
In the zstar_eu.f90, Born charges consist of two terms as seen below: a part
due to polarization calculation (dynamic)
