I think the Ecut is small. Did you test the its convergence to total energy? Otherwise, your large electric field maybe lead to the convergence harder. Try large Ecut and small field, good luck!<p>ÔÚ2014-10-21 18:11:15£¬plgong<a href="mailto:plgong@theory.issp.ac.cn" target="_blank">plgong@theory.issp.ac.cn</a>дµÀ£º</p><blockquote name="replyContent" style="padding-left: 1ex;margin: 0px 0px 0px 0.8ex;border-left: 1px solid #ccc;"><div>
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<div dir="ltr">Dear all<FONT style="FONT-SIZE: 12pt" size="3">,<BR></FONT><BR><FONT size="3">I am wanting to get the Dos of silicene under the effect of an external electric field. I have done the scf calculations without electric field , then again did the scf calculation with an electric field included in the z-direction (with value 0.008ua). But the convergence is not achieved and it stopped after 800 iterations and giving it this message:<BR></FONT><BR><FONT size="3"><BR></FONT><BR><I><FONT size="3">"total cpu time spent up to now is 20409.6 secs </FONT></I><BR><I></I><I><FONT size="3"></FONT></I><BR><I></I><I><FONT size="3">total energy = -64.27063591 Ry </FONT></I><BR><I></I><I><FONT size="3">Harris-Foulkes estimate = -62.93460760 Ry </FONT></I><BR><I></I><I><FONT size="3">estimated scf accuracy < 0.00003422 Ry </FONT></I><BR><I></I><I><FONT size="3"></FONT></I><BR><I></I><I><FONT size="3">End of self-consistent calculation </FONT></I><BR><I></I><I><FONT size="3"></FONT></I><BR><I></I><I></I><FONT size="3"><I>convergence NOT achieved after 800 iterations: stopping"</I><BR></FONT><BR><FONT size="3"><BR></FONT><BR><FONT size="3"><BR></FONT><BR><FONT size="3">You will find below in file for the scf calculation when an electric field is applied:</FONT><BR><FONT size="3">&control </FONT><BR><FONT size="3">calculation='scf' </FONT><BR><FONT size="3">restart_mode='from_scratch', </FONT><BR><FONT size="3">prefix='elec0.08', </FONT><BR><FONT size="3">lelfield=.true., </FONT><BR><FONT size="3">nberrycyc=3 </FONT><BR><FONT size="3">pseudo_dir ='/home/siham/Desktop/espresso-5.0.1-GPU/pseudo', </FONT><BR><FONT size="3">outdir='/home/siham/Desktop/espresso-5.0.1-GPU/tmp' </FONT><BR><FONT size="3">/ </FONT><BR><FONT size="3">&system </FONT><BR><FONT size="3">ibrav= 1, celldm(1)=10.18, nat= 8, ntyp= 1, </FONT><BR><FONT size="3">ecutwfc = 20.0 </FONT><BR><FONT size="3">/ </FONT><BR><FONT size="3">&electrons </FONT><BR><FONT size="3">electron_maxstep=800, </FONT><BR><FONT size="3">diagonalization='david', </FONT><BR><FONT size="3">conv_thr = 1.0d-8, </FONT><BR><FONT size="3">mixing_beta = 0.5, </FONT><BR><FONT size="3">startingwfc='random', </FONT><BR><FONT size="3">efield_cart(1)=0.d0,efield_cart(2)=0.d0,efield_cart(3)=0.008d0 </FONT><BR><FONT size="3">/ </FONT><BR><FONT size="3">ATOMIC_SPECIES </FONT><BR><FONT size="3">Si 28.086 Si.pbe-rrkj.UPF </FONT><BR><FONT size="3">ATOMIC_POSITIONS </FONT><BR><FONT size="3">Si -0.125 -0.125 -0.125 </FONT><BR><FONT size="3">Si 0.375 0.375 -0.125 </FONT><BR><FONT size="3">Si 0.375 -0.125 0.375 </FONT><BR><FONT size="3">Si -0.125 0.375 0.375 </FONT><BR><FONT size="3">Si 0.125 0.125 0.125 </FONT><BR><FONT size="3">Si 0.625 0.625 0.125 </FONT><BR><FONT size="3">Si 0.625 0.125 0.625 </FONT><BR><FONT size="3">Si 0.125 0.625 0.625 </FONT><BR><FONT size="3">K_POINTS {automatic} </FONT><BR><FONT size="3">3 3 7 0 0 0</FONT><BR><BR><BR><FONT style="FONT-SIZE: 12pt" size="3">Thanks in advance</FONT><BR><BR>
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