Dear Shyam, Nothing is wrong with your calculations. The message just states you have metallic system (find a line with "F" in your IFC file), but not semiconducting. "F" (FALSE) means your IFC file does not contain neither macroscopic dielectric constant, nor Born effective charges (hence, LO-TO splitting) which are relevant for semiconducting(insulating) system. Please have a look at a textbok, why?
Bests, Eyvaz. ------------------------------------------------------------------- Prof. Eyvaz Isaev, Theoretical Physics Department, Moscow State Institute of Steel & Alloys, Russia, Department of Physics, Chemistry, and Biology (IFM), Linkoping University, Sweden Condensed Matter Theory Group, Uppsala University, Sweden Eyvaz.Isaev at fysik.uu.se, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com --- On Tue, 1/26/10, Shyam Khambholja <physik.shyam at gmail.com> wrote: > From: Shyam Khambholja <physik.shyam at gmail.com> > Subject: [Pw_forum] About phonon dispersion > To: pw_forum at pwscf.org > Date: Tuesday, January 26, 2010, 10:57 AM > Dear all, > ??????????? I want to compute phonon > dispersion curves for nickel. when running q2r.in file, > ??????????? I am getting following > message. > ? > ?????????? reading?grid info from file > ni.dyn0 > ?????????? reading force constants from file > ni.dyn1 > ?????????? Dielectric tensor not > found. > ???????????nqs=1 > ????????? q = 0.00 0.00 0.00 > ????????? > ? > ?please tell me the error in ni.ph.in > file. > ? > ? Here is the ni.ph.in file > ################################################# > > &inputph > ? > tr2_ph=1.0d-14, > ? > prefix='ni', > ? > ldisp=.true., > ? > nq1=4, > ? > nq2=4, > ? > nq3=4, > ? > amass(1)=58.71, > ? > outdir='/home/birju/tmp/', > ? > fildyn='ni.dyn', > ?/ > ########################################### > ??????Also, when I am running matdyn.x > program,?I am getting following message. > ? > > ???? > from matdyn : info #??????? > -1 > ???? Z* not found in file > ni444.fc, TO-LO splitting at q=0 will be absent! > > ???? A direction for q was not > specified:TO-LO splitting will be absent > ???? from matdyn : info #??????? -1 > > ???? Z* not found in file > ni444.fc, TO-LO splitting at q=0 will be absent! > ???? A direction for q was not > specified:TO-LO splitting will be absent > > ??????????? > So, > please help me.? > Thanks > in advance. > -- > Shyam G Khambholja > Reseach student, > Depratment of Physics, > Sardar Patel University > > -----Inline Attachment Follows----- > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum >
