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<p>Dear Erica, dear Lorenzo,</p>
<p>just to add to what Lorenzo said:</p>
<ul>
<li> as far as I know mostly the PAW coded write the
pseudo-wavefunction into the UNK files, therefore the number of
nodes cannot be reproduced in Wannier functions. At least it is
true for VASP and QuantumEspresso. The reasons are twofold: (i)
noone bothered to code plotting all-electron wavefunction, (ii)
the all-electron wavefunction strongly oscillates near the core,
therefore a very dense real-space grid is needed to represent
it. <br>
</li>
<li>The Wannier function may have additional nodes far from the
the center (usually near the neighboring atoms, or even further)
but those are not related to the nodes of atomic wavefunctions.</li>
<li>According to the page <a class="moz-txt-link-freetext" href="http://www.wannier.org/features/">http://www.wannier.org/features/</a> ,
Wannier90 is interfaced with Fleur and Wien2k, but I am not
familiar with those, I do not know if/how they write the UNK
files.</li>
<li>I fully agree with Lorenzo's conclusion:<br>
<blockquote type="cite">Finally, if all you need is a pretty
picture, I don't think it is worth it. If you need the correct
all-electron wavefunction close to the core, I'm not sure
wannierization is the best method.
<br>
</blockquote>
</li>
</ul>
Regards,
<p>Stepan</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 03.11.20 10:41, Lorenzo Paulatto
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:c1a83c24-8389-873e-56de-db2037c68a54@gmail.com">
<br>
<br>
On 11/3/20 7:55 AM, Erica Kotta wrote:
<br>
<blockquote type="cite">The plots in xcrysden I've come across
only show the lowest-level orbitals for each l-value (for
example only 2p orbital character, even when you know that the
bands of interest are 3p or 4p). I thought that by getting the
underlying xsf numerical data or recreating the plots from the
Umn/UNK files, I would be able to resolve the "missing" nodes.
<br>
</blockquote>
Hello Erica,
<br>
this is not a limitation of the wannierization method, but of the
pseudo-potential approximation. The Wannier90 only works with what
it gets from the total energy code.
<br>
<br>
I don't know if Wannier90 can interface with any all-electron code
<br>
<br>
In principle if you use PAW pseudopotential, or with a GIPAW-like
method, it is possible to reconstructs the all-electron
wavefunctions from a pseudopotential calculation, but I do not
think it has ever been done in conjunction with wannierization.
<br>
<br>
Finally, if all you need is a pretty picture, I don't think it is
worth it. If you need the correct all-electron wavefunction close
to the core, I'm not sure wannierization is the best method.
<br>
<br>
cheers
<br>
<br>
<br>
</blockquote>
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