Hi Laurence,
Sorry for the delay in getting back
I think the issue is that at present Wien2k does not really add a
constant charge background and calculate the self-energy of this
charge (in a given potential), it instead add the potential associated
with this charge.
Yes, sounds like
Thank you for the answers. The problem now becomes more clear to me.
The question is then how to do a realistic charged cell calculation
with meaningful energies taking account of the effect of a potential
shift? If vacuum is available one can determine the potential shift
and correct; one
I think the issue is that at present Wien2k does not really add a
constant charge background and calculate the self-energy of this
charge (in a given potential), it instead add the potential associated
with this charge. If one has N-1 electrons, a nuclear charge of N,
only N-1 eigenvalues are
Hi Peter,
In the integrals below, \rho is just the electronic charge density
(without nuclei).
Thus c \int{\rho] does NOT vanish and gives c * NE (number of
electrons).
However, if rho comes from electronic states, each eigenvalue is
shifted by the constant c
and thus the sum of
Thank you for the replies. I thought that such a correction was
already done in Wien2k. I should have noticed the warning in case.scf0
file:
:WARN :CHARGED CELL with -1.000
an energy correction like C Q**2/(L eps) is not included
(PRB51,4014; PRB73,35215)
I'm not sure if I
Dear Prof. Blaha,
I have another question on the topic. Does this problem also affect
the other quantities such as electron density, DOS and forces? If I
need to perform a geometric optimization after I have added a charge,
should I also apply the correction to the forces in order to get the
I think the forces are going to be OK, the issue is a constant energy
correction for the nominal background charge. Since this should be
constant, I don't think it will contribute at all to forces which
depend upon gradients.
On Thu, Feb 25, 2010 at 6:07 AM, Yurko Natanzon
yurko.natanzon at
As mentioned before, the potential (and thus the density) should be ok.
With respect to forces I'd suggest you run a simple test. Take a simple
compound which has forces,
charge it, and compare the forces and the total energy.
You can test it even better by taking eg. your GaN, reduce the
Dear Peter,
Yes, the background charge must be taken into account as part of the
net-neutral total charge in order to have well-defined total energy.
Then as long as the compensation charge is then in exactly the same
way as the remaining physical charge (i.e., enters all the same
Dear Prof. Blaha and Prof. Marks,
Thank you for your replies.
I'm afraid about the following thing: the Markove-Payne-like (Phys.
Rev. B 51, 4014) correction you propose should cancel the error which
exists due to the repulsion of charged defects in the periodic crystal
and results in some
In the integrals below, \rho is just the electronic charge density (without
nuclei).
Thus c \int{\rho] does NOT vanish and gives c * NE (number of electrons).
However, if rho comes from electronic states, each eigenvalue is shifted by the
constant c
and thus the sum of eigenvalues cancels the c
Dear Wien2k users and developers,
I'd like to refresh the discussion about the total energies of the
charged cells which took place three years ago:
http://zeus.theochem.tuwien.ac.at/pipermail/wien/2007-January/008711.html
I'm trying to calculate the formation energy of the Hydrogen vacancy
in
Please see the next email on the list:
http://zeus.theochem.tuwien.ac.at/pipermail/wien/2007-January/008713.html
I think this is right and you take V0 from case.output0 (it is printed
there). You should do an empty cell test (no electrons) to verify this
and the units of V0, perhaps also looking
I've started some tests after the first query and it seems we might miss a term
in the total
energy.
I created a clmsum-file (density) which is constant and is normalized to one
and put this into
a cell with a single H nucleus.
So it refers to the test case of a H+ ion in a lattice, where I do
14 matches
Mail list logo
