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<p>Dear QE-developers,</p>
<p>the flag "lsym" in projwfc.x turns ON/OFF (default: ON) the
symmetrization of the atomic states.<br>
</p>
<p>If .false., the partialdos is not computed. While this check is
generally necessary to compute the DOS integrated on the full BZ
by performing the summation only over the irreducible one, it is
too restrictive when computing the DOS in special cases.</p>
<p>In particular, if you want to compute the bands of a system that
has some symmetry (e.g. px=py for a square lattice) that is not
retained by the k-point path for example from k=(0,0,0) to
k=(1/2,0,0). In that case, lsym=.true. would produce the same
result for px and py also at k/=(0,0,0). To disentangle them, it
is sufficient to remove the check(*). This applies to the case
"kresolveddos=.true".<br>
</p>
<p>Practically, my tiny suggestion is to replace the check "IF
(lsym) THEN" in PP/src/projwfc.f90 with "IF (lsym .OR.
kresolveddos) THEN"<br>
</p>
<p><br>
</p>
<p><br>
</p>
<pre> ELSE IF ( lsym .OR. kresolveddos ) THEN
IF (noncolin) THEN
CALL partialdos_nc (Emin, Emax, DeltaE, kresolveddos, filpdos)
ELSE
CALL partialdos (Emin, Emax, DeltaE, kresolveddos, filpdos)
ENDIF
ENDIF
</pre>
<p><br>
</p>
<p>and to change the specification of the variable in the input file
PP/Doc/INPUT_PROJWFC.def as:<br>
</p>
<pre style="margin-bottom: -1em;">if .true. the projections are symmetrized and partial density of states computed.
if .false. the projections are symmetrized; partial density of state are computed only in the k-resolved case.
</pre>
<p>On the contrary, I still don't see a case where one would set
lsym=.false., kresolveddos=.false., and still like to compute the
partial DOS.<br>
</p>
<p>Kind regards,</p>
<p>Guido</p>
<p><br>
</p>
<p>(*) alternatively, one could remove the symmetry by straining the
lattice. I tested it by taking a square lattice, lsym=.false., and
the same strained by 0.01% and the results are indeed equivalent.<br>
</p>
<pre class="moz-signature" cols="72">--
Guido Fratesi
Dipartimento di Fisica
Universita` degli Studi di Milano
Via Celoria 16, 20133 Milano, Italy
Phone: +39 02 503 17348
email: <a class="moz-txt-link-abbreviated" href="mailto:guido.fratesi@unimi.it">guido.fratesi@unimi.it</a>
web: <a class="moz-txt-link-freetext" href="https://sites.google.com/site/guidofratesi/">https://sites.google.com/site/guidofratesi/</a>
</pre>
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