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<p><b>Short answer</b><br>
</p>
<p>The WIEN2k webpage has the sentence [1]:<br>
</p>
<p><i>The linearized augmented plane wave (LAPW) method is among the
most accurate methods for performing electronic <b>structure
calculations for crystals</b>.</i></p>
<p>Amorphous is defined in [2] as non-crystalline and in [3] it
means "shapeless" and defined an arrangement of particles that do
not form crystals. Thus, a strict definition of <b>amorphous is
not a crystal</b>.<br>
</p>
<p>Under this strict definition the calculation would not be
possible. WIEN2k requires you to provide a crystal structure with
a periodic arrangement using lattice parameters and atomic
positions (e.g. StructGen). A completely amorphous material would
be a non-periodic arrangement with randomly positioned atomic
positions such that there would no lattice parameters.</p>
<p><b>Long answer</b></p>
<p>Directly quoting [4] that uses a less strict definition of
amorphous which states:</p>
<p><i>It is often said that amorphous materials have no structure.
This is not strictly true...</i><br>
</p>
<p>As described by [5], amorphous is not all the way random and has
some order.</p>
<p>With WIEN2k, multiple supercell calculations and averaging can be
used for an amorphous solid but it can be expected to be
computational expensive. Thus, it is only be possible if you have
the computational resources for the computation. This is
paraphrased from the following cited references which you can look
to for more information:<br>
</p>
<p>At [6], it has ... <i>average over all inequivalent occupations
of the sites but this may need large number of calculations for
large supercells</i>...<br>
</p>
<p>Link [7] has ... <i>you can also make an averaging over few
calculations of few different unit cells</i> ....</p>
<p>Per [8], ... <i>An alloy is DISORDERED and you need to simulate
that by some random distribution of the atoms in a supercell
which should be as large as possible.</i></p>
<p>Within section I. INTRODUCTION in [9] there is: <i>... the
WIEN2k code is an example of the latter. We represent the solid
by a unit cell, which is repeated in all three directions,
corresponding to periodic boundary conditions. This assumes that
the solid is perfect, ordered, and infinite; however, a real
crystal differs from this ideal situation, since it is finite,
may contain defects or impurities, and may deviate from its
ideal stoichiometry. For these important aspects and how to
handle them using supercells, see Chap. 8.2 of Ref. 4.</i><br>
<br>
While [10] has: <i>One needs to use larger supercells and either
a "quasi-random structure" or at least test a couple of
arrangements of your impurities (more nearest-neigbors or far
away, ...)</i> <br>
</p>
<p>A reference for quasi-random structure is [11].</p>
<p>There is other literature that may be of interest to you such as
[12,13], "Monte Carlo study of magnetic structures in rare-earth
amorphous alloys<i>"</i> by A. Bondarev et. al. [14], "Recent
Developments in Computer Modeling of Amorphous Materials" by D. A.
Brabold et. al. [15], and "Materials modeling by design:
applications to amorphous solids" by P. Biswas et. al. [16].<br>
</p>
[1] <a class="moz-txt-link-freetext" href="http://susi.theochem.tuwien.ac.at/lapw/index.html">http://susi.theochem.tuwien.ac.at/lapw/index.html</a><br>
[2] Slide 9:
<a class="moz-txt-link-freetext" href="https://www.feis.unesp.br/Home/departamentos/engenhariamecanica/maprotec/5aula_cme.pdf">https://www.feis.unesp.br/Home/departamentos/engenhariamecanica/maprotec/5aula_cme.pdf</a><br>
[3] <a class="moz-txt-link-freetext" href="https://www.ck12.org/chemistry/solid/lesson/Solids-MS-PS/">https://www.ck12.org/chemistry/solid/lesson/Solids-MS-PS/</a><br>
- Of note, "amorphous" is Greek for "without shape":
<a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Amorphous_solid">https://en.wikipedia.org/wiki/Amorphous_solid</a><br>
[4] <a class="moz-txt-link-freetext" href="http://pd.chem.ucl.ac.uk/pdnn/diff1/recip.htm">http://pd.chem.ucl.ac.uk/pdnn/diff1/recip.htm</a><br>
[5]
<a class="moz-txt-link-freetext" href="https://www.doitpoms.ac.uk/tlplib/atomic-scale-structure/intro.php">https://www.doitpoms.ac.uk/tlplib/atomic-scale-structure/intro.php</a><br>
[6]
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg05007.html">https://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg05007.html</a><br>
[7]
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg12106.html">https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg12106.html</a><br>
[8]
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg09398.html">https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg09398.html</a><br>
[9] <a class="moz-txt-link-freetext" href="https://doi.org/10.1063/1.5143061">https://doi.org/10.1063/1.5143061</a><br>
[10]
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg19766.html">https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg19766.html</a><br>
[11] <span class="doi-field"><a class="moz-txt-link-freetext" href="https://doi.org/10.1103/PhysRevLett.65.353">https://doi.org/10.1103/PhysRevLett.65.353</a></span><br>
<span class="doi-field">[12] <a class="moz-txt-link-freetext" href="https://doi.org/10.5402/2012/736341">https://doi.org/10.5402/2012/736341</a></span><br>
<span class="doi-field">[13] <a class="moz-txt-link-freetext" href="https://arxiv.org/pdf/2201.06986v1.pdf">https://arxiv.org/pdf/2201.06986v1.pdf</a></span><br>
<span class="doi-field">[14]
<a class="moz-txt-link-freetext" href="https://doi.org/10.1051/epjconf/201818504017">https://doi.org/10.1051/epjconf/201818504017</a></span><br>
<span class="doi-field">[15]
<a class="moz-txt-link-freetext" href="https://arxiv.org/ftp/cond-mat/papers/0312/0312607.pdf">https://arxiv.org/ftp/cond-mat/papers/0312/0312607.pdf</a></span><br>
<span class="doi-field">[16]
<a class="moz-txt-link-freetext" href="https://doi.org/10.1088/0953-8984/21/8/084207">https://doi.org/10.1088/0953-8984/21/8/084207</a></span><br>
<p><span class="doi-field">Kind Regards,</span></p>
<span class="doi-field">Gavin</span><br>
<span class="doi-field">WIEN2 user<br>
</span>
<p><span class="doi-field"></span></p>
<div class="moz-cite-prefix">On 1/19/2022 8:56 AM, sherif Yehia
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAGGXTFJD+AaP5ptseU1m344MVcarOrUtyeJ-eS9RsHvdWBd0eA@mail.gmail.com">
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<div dir="ltr">Dear Wien2k experts and users<br>
</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">I would like to ask your kind help to clarify the
following question to me.<br>
</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">We are interested in calculating some physical
properties of amorphous binary rare-earth transition metal
alloys e.g. GdxCo1-x , for example Gd0.16Co 0.84 using
Wien2k code. Is there a possibility to calculate the magnetic
moment, DOS and/or other magnetic properties of amorphous
materials in general and for the above-mentioned alloys in
particular? Any comment or advice is appreciated.<br>
</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Thanks all for your help and guidance <br>
</div>
<div dir="ltr"><br>
</div>
<div>Sherif Yehia<br>
</div>
</div>
</blockquote>
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