<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div dir="ltr" id="yui_3_16_0_1_1425219817587_2927"><span id="yui_3_16_0_1_1425219817587_2926">Pang, when you advise to change mixing steps, are you suggesting to change mixing_ndim or mixing_fixed_ns ? I'm not sure the effect of either one, can you please explain?</span></div><div dir="ltr" id="yui_3_16_0_1_1425219817587_2927"><span id="yui_3_16_0_1_1425219817587_6335">Turning off spin polarization might get to a different ionic ground state -- I'm starting from a converged ionic ground state and then changing the doping by swapping out one atom per unit cell, so I'm already fairly close to a ground state, and I'm just trying to get the last increment of convergence.</span></div><div dir="ltr" id="yui_3_16_0_1_1425219817587_2927"><span><br></span></div><div dir="ltr" id="yui_3_16_0_1_1425219817587_2927"><span id="yui_3_16_0_1_1425219817587_4636">Thanks MVKondrin. etot_conv_thr, as I understand it, controls the delta E convergence threshold between ionic steps of a geometry relaxation (i.e. after electron SCF convergence in a given geometry). I'm seeing non-convergence in SCF steps, and I believe conv_thr (&electrons namelist) controls the SCF convergence. A fair question would be, "should I increase conv_thr?" -- to which I'm taking a conservative route and hoping to get good SCF convergence in each ion step.</span></div> <div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"> <font size="2" face="Arial"> On Sunday, February 22, 2015 6:53 AM, MKondrin <mkondrin@hppi.troitsk.ru> wrote:<br> </font> </div> <br><br> <div class="y_msg_container">talpha beta wrote:<div class="yqt0126999771" id="yqtfd98017"><br clear="none">> I'm having lots of trouble getting SCF convergence during a vc-relax <br clear="none">> calculation. The first ~30 geometry relaxation steps will converge, <br clear="none">> and then at some point, it doesn't reach convergence, and restarting <br clear="none">> from there doesn't obtain convergence with a variety of input <br clear="none">> parameters. I allow up to 400 steps for convergence; the calculation <br clear="none">> gets close to energy convergence in the first ~40 steps and then <br clear="none">> oscillates like this:<br clear="none">><br clear="none">><br clear="none">><br clear="none">> total energy = -3730.97262054 Ry<br clear="none">> total energy = -3730.97260717 Ry<br clear="none">> total energy = -3730.97261229 Ry<br clear="none">> total energy = -3730.97261830 Ry<br clear="none">> total energy = -3730.97258457 Ry<br clear="none">> total energy = -3730.97261372 Ry<br clear="none">> total energy = -3730.97268144 Ry<br clear="none">> total energy = -3730.97262740 Ry<br clear="none">> total energy = -3730.97259749 Ry<br clear="none">> total energy = -3730.97264306 Ry<br clear="none">> total energy = -3730.97263999 Ry<br clear="none">> total energy = -3730.97266124 Ry<br clear="none">> total energy = -3730.97263072 Ry<br clear="none">> total energy = -3730.97261754 Ry<br clear="none">> total energy = -3730.97260856 Ry<br clear="none">> total energy = -3730.97261221 Ry<br clear="none">> total energy = -3730.97282659 Ry<br clear="none">> total energy = -3730.97252377 Ry<br clear="none">> total energy = -3730.97259997 Ry<br clear="none">> total energy = -3730.97261600 Ry<br clear="none">> total energy = -3730.97264186 Ry<br clear="none">> total energy = -3730.97263070 Ry<br clear="none">> total energy = -3730.97260955 Ry<br clear="none">> total energy = -3730.97267593 Ry<br clear="none">> total energy = -3730.97263180 Ry<br clear="none">> total energy = -3730.97259580 Ry<br clear="none">> total energy = -3730.97269934 Ry<br clear="none">> total energy = -3730.97275706 Ry<br clear="none">> total energy = -3730.97245909 Ry<br clear="none">> total energy = -3730.97258422 Ry<br clear="none">> total energy = -3730.97257852 Ry<br clear="none">> total energy = -3730.97255901 Ry<br clear="none">> total energy = -3730.97259179 Ry<br clear="none">> total energy = -3730.97262199 Ry<br clear="none">> total energy = -3730.97259627 Ry<br clear="none">> total energy = -3730.97261363 Ry<br clear="none">> total energy = -3730.97262780 Ry<br clear="none">> total energy = -3730.97273314 Ry<br clear="none">> total energy = -3730.97251796 Ry<br clear="none">> total energy = -3730.97259430 Ry<br clear="none">> total energy = -3730.97258802 Ry<br clear="none">> total energy = -3730.97257319 Ry<br clear="none">> total energy = -3730.97257817 Ry<br clear="none">> total energy = -3730.97254693 Ry<br clear="none">> total energy = -3730.97253977 Ry<br clear="none">> total energy = -3730.97254394 Ry<br clear="none">> total energy = -3730.97254471 Ry<br clear="none">> total energy = -3730.97282186 Ry<br clear="none">> total energy = -3730.97250548 Ry<br clear="none">> total energy = -3730.97248482 Ry<br clear="none">> total energy = -3730.97247040 Ry<br clear="none">> total energy = -3730.97239243 Ry<br clear="none">> total energy = -3730.97226787 Ry<br clear="none">> total energy = -3730.97222104 Ry<br clear="none">> total energy = -3730.97219271 Ry<br clear="none">> total energy = -3730.97222772 Ry<br clear="none">> total energy = -3730.97244430 Ry<br clear="none">> total energy = -3730.97291917 Ry<br clear="none">> total energy = -3730.97279625 Ry<br clear="none">> total energy = -3730.97207455 Ry<br clear="none">> total energy = -3730.97249466 Ry<br clear="none">> total energy = -3730.97247870 Ry<br clear="none">> total energy = -3730.97252112 Ry<br clear="none">> total energy = -3730.97253986 Ry<br clear="none">> total energy = -3730.97254804 Ry<br clear="none">> total energy = -3730.97264250 Ry<br clear="none">> total energy = -3730.97257019 Ry<br clear="none">> total energy = -3730.97258495 Ry<br clear="none">> total energy = -3730.97282802 Ry<br clear="none">> total energy = -3730.97259481 Ry<br clear="none">> total energy = -3730.97254903 Ry<br clear="none">> total energy = -3730.97252576 Ry<br clear="none">> total energy = -3730.97249424 Ry<br clear="none">> total energy = -3730.97237618 Ry<br clear="none">> total energy = -3730.97263210 Ry<br clear="none">> total energy = -3730.97248594 Ry<br clear="none">> total energy = -3730.97240941 Ry<br clear="none">> total energy = -3730.97283533 Ry<br clear="none">> total energy = -3730.97270373 Ry<br clear="none">> total energy = -3730.97250770 Ry<br clear="none">> total energy = -3730.97252933 Ry<br clear="none">> total energy = -3730.97254547 Ry<br clear="none">> total energy = -3730.97250286 Ry<br clear="none">> total energy = -3730.97247847 Ry<br clear="none">> total energy = -3730.97244537 Ry<br clear="none">> total energy = -3730.97244642 Ry<br clear="none">> total energy = -3730.97241718 Ry<br clear="none">> total energy = -3730.97242648 Ry<br clear="none">> total energy = -3730.97296957 Ry<br clear="none">> total energy = -3730.97258207 Ry<br clear="none">> total energy = -3730.97250996 Ry<br clear="none">> total energy = -3730.97271424 Ry<br clear="none">> total energy = -3730.97258977 Ry<br clear="none">> total energy = -3730.97259733 Ry<br clear="none">> total energy = -3730.97264651 Ry<br clear="none">> total energy = -3730.97263695 Ry<br clear="none">> total energy = -3730.97259491 Ry<br clear="none">> total energy = -3730.97261988 Ry<br clear="none">> total energy = -3730.97272206 Ry<br clear="none">> total energy = -3730.97261538 Ry<br clear="none">> total energy = -3730.97256870 Ry<br clear="none">> total energy = -3730.97252499 Ry<br clear="none">> total energy = -3730.97252092 Ry<br clear="none">> total energy = -3730.97252172 Ry<br clear="none">> total energy = -3730.97257641 Ry<br clear="none">> total energy = -3730.97256721 Ry<br clear="none">> total energy = -3730.97257116 Ry<br clear="none">> total energy = -3730.97256679 Ry<br clear="none">> total energy = -3730.97274213 Ry<br clear="none">> total energy = -3730.97253146 Ry<br clear="none">> total energy = -3730.97249600 Ry<br clear="none">> total energy = -3730.97250428 Ry<br clear="none">> total energy = -3730.97254304 Ry<br clear="none">> total energy = -3730.97256978 Ry<br clear="none">> total energy = -3730.97273656 Ry<br clear="none">> total energy = -3730.97248342 Ry<br clear="none">> total energy = -3730.97240302 Ry<br clear="none">> total energy = -3730.97243408 Ry<br clear="none">> total energy = -3730.97241248 Ry<br clear="none">> total energy = -3730.97238562 Ry<br clear="none">> total energy = -3730.97251359 Ry<br clear="none">> total energy = -3730.97247234 Ry<br clear="none">> total energy = -3730.97264369 Ry<br clear="none">> total energy = -3730.97259674 Ry<br clear="none">> total energy = -3730.97266736 Ry<br clear="none">> total energy = -3730.97257325 Ry<br clear="none">> total energy = -3730.97247542 Ry<br clear="none">> total energy = -3730.97252150 Ry<br clear="none">> total energy = -3730.97248097 Ry<br clear="none">> total energy = -3730.97246945 Ry<br clear="none">> total energy = -3730.97253380 Ry<br clear="none">> total energy = -3730.97255385 Ry<br clear="none">> total energy = -3730.97254624 Ry<br clear="none">> total energy = -3730.97277355 Ry<br clear="none">> total energy = -3730.97261952 Ry<br clear="none">> total energy = -3730.97255316 Ry<br clear="none">> total energy = -3730.97253355 Ry<br clear="none">> total energy = -3730.97247700 Ry<br clear="none">> total energy = -3730.97253033 Ry<br clear="none">> total energy = -3730.97247318 Ry<br clear="none">> total energy = -3730.97244662 Ry<br clear="none">> total energy = -3730.97246907 Ry<br clear="none">> total energy = -3730.97244103 Ry<br clear="none">> total energy = -3730.97306304 Ry<br clear="none">> total energy = -3730.97245649 Ry<br clear="none">> total energy = -3730.97247788 Ry<br clear="none">> total energy = -3730.97281807 Ry<br clear="none">> total energy = -3730.97269524 Ry<br clear="none">> total energy = -3730.97274703 Ry<br clear="none">> total energy = -3730.97267068 Ry<br clear="none">> total energy = -3730.97251186 Ry<br clear="none">> total energy = -3730.97245086 Ry<br clear="none">> total energy = -3730.97258230 Ry<br clear="none">><br clear="none">> I input a starting_magentization value close to the converged values <br clear="none">> from previous runs<br clear="none">> I increase the number of bands (nbnd) to well above #electrons/2<br clear="none">> diagonalization = 'cg' or 'david'<br clear="none">> electron_maxstep = 400<br clear="none">> mixing_mode = 'plain' or 'local-TF'<br clear="none">> mixing_beta = as low as 0.05<br clear="none">><br clear="none">> what are the other tricks/tips to obtain convergence? </div><br clear="none">><br clear="none">><br clear="none">> ------------------------------------------------------------------------<br clear="none">><br clear="none">> _______________________________________________<br clear="none">> Pw_forum mailing list<br clear="none">> <a shape="rect" ymailto="mailto:Pw_forum@pwscf.org" href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br clear="none">> <a shape="rect" href="http://pwscf.org/mailman/listinfo/pw_forum" target="_blank">http://pwscf.org/mailman/listinfo/pw_forum</a><br clear="none">Wouldn't you just increase etot_conv_thr (in &control namelist) to some <br clear="none">larger value? The total energy is high enough so the oscillation at the <br clear="none">level of 1e-8 of the absolute value may be due to the calculation errors.<br clear="none"><br clear="none">M. V. Kondrin<div class="yqt0126999771" id="yqtfd82896"><br clear="none"></div><br><br></div> </div> </div> </div> </div></body></html>