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<DIV><FONT size=2>Dear all,</FONT></DIV>
<DIV><FONT size=2>I have some questions about Phonon calculation.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>1. If I use ph.x to run the graphene phonon dispersion and
pdos</FONT><FONT size=2>,</FONT></DIV>
<DIV><FONT size=2> should I use the q points which is
multiple of 6 because of the hexagonal shape of grathpene crystal?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>2. When I run phonon-dispersion calculation, it always cost
very long cpu time. Is that normal?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>3. </FONT><FONT size=2>Can QE calculate vibration
mode?</FONT></DIV>
<DIV><FONT size=2> How could I set terms in ph.in to get
vibration mode? </FONT></DIV>
<DIV><FONT size=2> And how could I plot the
vibration mode from the output file?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Thanks a lot.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>best regards,</FONT></DIV>
<DIV><FONT size=2>Yu Han Ho</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2></FONT> </DIV></BODY></HTML>