<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">I may be wrong, but your problem could be due to subtelties of the US PP formalism. Using US PPs, I am afraid that PW calculations are variational with respect to PW expansion coefficients only when the augmentation charge is at convergence. Convergence with respect to the augmentation charge usually is a rather delicate issue. For sure, the cutoff for the charge-density distribution (ecutrho) should be taken larger (sometimes much larger) than the default value for norm-conserving PPs (4 x ecutwfc). In yor calculation, you seem to use just this value, which may turn out to be inadequate. Have you tried to test the convergence of your calcs wrt echutrho (keeping ecutwfc fixed)? SB<div><br><div><div>On Jun 22, 2008, at 11:06 AM, hania djani-ait aissa wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div class="hmmessage" style="font-size: 10pt; font-family: Tahoma; ">Dear Nicola,<br>I have tried startingwfc='random' and it gave me the same energies values as for startingwfc='atomic' with still the same problem of drop and rise of total energy. I also increase Ecutoff to 40Ry, the energies values are actually more accurate but the problem persist.<br> <br>Hania<br> <br> <br><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "><span lang="EN-GB"><font color="#000000"><font face="Courier New"><span> </span>&control<br><span> <span class="Apple-converted-space"> </span></span>calculation<span> <span class="Apple-converted-space"> </span></span>= 'scf'<br><span> <span class="Apple-converted-space"> </span></span>restart_mode = 'from_scratch'<br><span> <span class="Apple-converted-space"> </span></span>pseudo_dir<span> <span class="Apple-converted-space"> </span></span>= '/root/pwscf/pseudo/'<br><span> <span class="Apple-converted-space"> </span></span>outdir<span> <span class="Apple-converted-space"> </span></span>= '/root/tmp/'<br><span> </span>/<br><span> </span>&system<br><span> <span class="Apple-converted-space"> </span></span>ibrav=7<br><span> <span class="Apple-converted-space"> </span></span>celldm(1)=7.33, celldm(3)=8.54<br><span> <span class="Apple-converted-space"> </span></span>nat=19<br><span> <span class="Apple-converted-space"> </span></span>ntyp=3<br><span> <span class="Apple-converted-space"> </span></span>ecutwfc=25.0<br><span> <span class="Apple-converted-space"> </span></span>ecutrho=100.0<br><span> </span>/<br><span> </span>&electrons<br><span> <span class="Apple-converted-space"> </span></span>conv_thr = 1e-6,<br><span> <span class="Apple-converted-space"> </span></span>mixing_beta=0.2,<o:p></o:p></font></font></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "><span lang="EN-GB"><font color="#000000"><font face="Courier New"><span> <span class="Apple-converted-space"> </span></span>startingwfc=’random’<br><span> </span>/<br>ATOMIC_SPECIES<br><span> <span class="Apple-converted-space"> </span></span>Bi<span> <span class="Apple-converted-space"> </span></span>208.98<span> <span class="Apple-converted-space"> </span></span>Bi.pbe-d-mt.UPF<br><span> <span class="Apple-converted-space"> </span></span></font></font></span><font color="#000000"><font face="Courier New"><span lang="IT">Ti<span> <span class="Apple-converted-space"> </span></span>47.867<span> <span class="Apple-converted-space"> </span></span>Ti.pbe-sp-van_ak.UPF<br><span> <span class="Apple-converted-space"> </span></span>O<span> <span class="Apple-converted-space"> </span></span>15.9994<span> <span class="Apple-converted-space"> </span></span>O.pbe-van_ak.UPF<br></span>ATOMIC_POSITIONS<span class="Apple-converted-space"> </span><br><span> </span>Bi 0.00000000 0.00000000 0.5713404<br><span> </span>Bi 0.00000000 0.00000000 7.9816596<br><span> </span>Bi 0.00000000 0.00000000 1.8072489<br><span> </span>Bi 0.00000000 0.00000000 6.7457511<br><span> </span></font></font><font color="#000000"><font face="Courier New"><span lang="IT">Ti 0.00000000 0.00000000 3.1757289<br><span> </span>Ti 0.00000000 0.00000000 5.3772711<br><span> </span>Ti 0.00000000 0.00000000 4.2765000<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.50000000 0.00000000 0.0000<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.50000000 0.0000<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.50000000 0.00000000 2.13825<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.50000000 0.00000000 6.41475<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.00000000 3.771873<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.00000000 4.781127<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.00000000 2.7241305<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.00000000 5.8288695<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.50000000 0.00000000 1.0049775<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.50000000 0.00000000 7.5480225<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.50000000 1.0049775<br><span> </span>O<span> <span class="Apple-converted-space"> </span></span>0.00000000 0.50000000 7.5480225<br>K_POINTS {automatic}<br><span> <span class="Apple-converted-space"> </span></span></span>4 4 4 1 1 1<br><o:p> </o:p></font></font></div> <br><br><hr>Téléchargez le nouveau Windows Live Messenger !<span class="Apple-converted-space"> </span><a href="http://get.live.com/messenger/overview" target="_new">Téléchargez Messenger, c'est gratuit !</a>_______________________________________________<br>Pw_forum mailing list<br><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br><a href="http://www.democritos.it/mailman/listinfo/pw_forum">http://www.democritos.it/mailman/listinfo/pw_forum</a><br></div></span></blockquote></div><br></div><br><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">---</span></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">Stefano Baroni - SISSA</span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "> </span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">&</span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "> </span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">DEMOCRITOS National Simulation Center - Trieste</span></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "><a href="http://www.sissa.it/~baroni">http://www.sissa.it/~baroni</a> / [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype)</span></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; font-size: 12px; "><br style="font-size: 12px; "></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; font-size: 12px; "><span class="Apple-style-span" style="font-size: 14px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">La morale est une logique de l'action comme la logique est une morale de la pensée - Jean Piaget</span></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "><br></span></font></div></span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">Please, if possible, don't</span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "> </span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">send me MS Word or PowerPoint attachments</span></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; ">Why? See:</span></font><font class="Apple-style-span" size="3"><span class="Apple-style-span" style="font-size: 12px; "> </span></font><font class="Apple-style-span" color="#0023E9" size="3"><span class="Apple-style-span" style="font-size: 12px; "><a href="http://www.gnu.org/philosophy/no-word-attachments.html">http://www.gnu.org/philosophy/no-word-attachments.html</a></span></font></div><div><font class="Apple-style-span" color="#0023E9" size="3"><span class="Apple-style-span" style="font-size: 12px; "><br class="webkit-block-placeholder"></span></font></div></div></div></span><br class="Apple-interchange-newline"></div></span><br class="Apple-interchange-newline"></div></span><br class="Apple-interchange-newline"></div></span><br class="Apple-interchange-newline"> </div><br></body></html>