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<font style="font-family: tahoma; font-size: 10pt;"><div style="font-family:
tahoma; font-size: 10pt;">Hi</div><div> </div></font><pre>(Do you mean
that the frequency obtained for the same q vector (0,0,0 in this case) is
<br>different if you perform a single q-point calculation w.r.t the
frequency obtained when <br>that q-point is included in a q-point grid (like
the 221 you mention). This seems quite <br>improbable to me.)</pre><font
style="font-family: tahoma; font-size: 10pt;"><div style="font-family:
tahoma; font-size: 10pt;">Well, I have to say that unfortunately your first
assumption is correct <br> Mehrnaz</div><div>Iran University of science
& technology </div></font>
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