<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt">Dear Ehsan,<br><br>I think there is no need for you to increase the maximum number of iterations for self consistency. You have bad input data. The periodic replica of atoms overlap with the others!!!<br><br>Graphene is a relatively small system. I will suggest that you modify your input file to describe the system within the <span style="font-weight: bold;">hexagonal symmetry (ibrav=4) and only two atoms</span> in the unit cell and a substantial vaccum in the z-direction. This is the normal representation of graphene.<br><br>HTH,<br><br>Bertrand<br><div><span><br></span></div><div> </div><div><span style="font-size:13px;"><span style="font-family:garamond, new york, times, serif;">***************************</span><span style="font-family:garamond, new york, times,
serif;">********</span><br><span style="font-family:garamond, new york, times, serif;"><b><span style="font-family:garamond, new york, times, serif;"><span style="font-family:garamond, new york, times, serif;"></span></span><span style="color:rgb(139, 139, 139);"><span style="font-weight:bold;">Bertrand SITAMTZE YOUMBI</span></span></b><span style="color:rgb(139, 139, 139);"><span style="font-weight:bold;"><br>PhD Materials Sciences</span><br></span><br><span style="color:rgb(115, 115, 115);">******CURRENT ADDRESS<br>IMMM, UMR CNRS 6283<br> Université du Maine<br>Le Mans, France<br>Tél: +33 6 67 61 52 15<br></span>*******************************</span><span style="font-family:garamond, new york, times, serif;">*********</span></span><span style="font-size:13px;"><span style="font-family:garamond, new york, times, serif;"></span></span></div><div style="display: block;" class="yahoo_quoted"> <br> <br> <div style="font-family: HelveticaNeue,
Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12pt;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12pt;"> <div dir="ltr"> <font face="Arial" size="2"> Le Lundi 25 novembre 2013 10h53, Lorenzo Paulatto <lorenzo.paulatto@impmc.upmc.fr> a écrit :<br> </font> </div> <div class="y_msg_container">On 11/24/2013 08:03 PM, ehsan targholi wrote:<br clear="none">> dear all pw users,<br clear="none">> my relax calculation is not converge after 100 iteration . please help me<br clear="none">> to find problem in input.<br clear="none">> my input is :<br clear="none"><br clear="none">Dear Ehsan,<br clear="none">there is something seriously wrong with your structure: the atoms appear<br clear="none">to be more or less on top of each other. If I double the size of the<br clear="none">first two unit cell axes it looks much more reasonable. Are you sure you<br
clear="none">did not apply the Bohr to Agstrom conversion twice?<br clear="none"><br clear="none">P.S. you normally need a small smearing to converge graphene. I think<br clear="none">there is a discussion of this in Phys. Rev. Lett. 93, 185503 (2004)<br clear="none"><br clear="none"><br clear="none">-- <br clear="none">Dr. Lorenzo Paulatto<br clear="none">IdR @ IMPMC -- CNRS & Université Paris 6<br clear="none">phone:+33 (0)1 44275 084 / skype: paulatz<br clear="none">www: <a shape="rect" href="http://www-int.impmc.upmc.fr/~paulatto/" target="_blank">http://www-int.impmc.upmc.fr/~paulatto/</a><br clear="none">mail: 23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 5<div class="yqt1242663730" id="yqtfd68368"><br clear="none">_______________________________________________<br clear="none">Pw_forum mailing list<br clear="none"><a shape="rect" ymailto="mailto:Pw_forum@pwscf.org"
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