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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Thanks, Alex and Paolo,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve tried replying to both of you (Alex, I’ve replied to separately through his direct e-mail address) on the Forum through the “reply” feature of Outlook, but for some reason it’s not working. I suspect it may be that I have some old PW_Forum registrations littering things up.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Paolo, I found the portion of subroutine dyndiag you referred to, and it should have been obvious to me that a non-hermitian issue is present. This may be due to the fact that the system, polysulfur nitride, I’m studying is “quite” monoclinic, and the nq Monkhorst-Pack grid (2x2x2) I’ve used does not sufficiently reflect this low symmetry. Is there a “rule of thumb” for setting the MP phonon grid for non-cubic systems? For calculating band structures and Fermi surfaces, even for low-symmetry metals, “cubic” grids seem to work OK in pw.x, whatever the unit cell symmetry may be, and yield expected results. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-Paul Grant, W2AGZ Technologies, JPL/CalTech<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>