<html><head></head><body><div style="font-family:Helvetica Neue;font-size:medium;"><div><div>Thank you Dr. Gerhard for the advice. I did as you said and it worked.<br></div></div><div><br></div><div>Regards</div><div>Jameela Fatheema</div><div>University of Peshawar<br></div><div id="yahoo_quoted_0859929105" class="yahoo_quoted"><div style="font-family:'Helvetica Neue', Helvetica, Arial, sans-serif;font-size:13px;color:#26282a;"><div>On Monday, July 17, 2017, 2:04:35 PM GMT+5, Fecher, Gerhard <fecher@uni-mainz.de> wrote:</div><div><br></div><div><br></div><div><div dir='ltr'><html><body>you need first to initialize the "low symmetry" structure with the displaced atom(s),<br clear="none">and afterwards run the "high" symmetry structure with the atoms placed back (do not accept symmetry changes during initialisation). <br clear="none"><br clear="none">Ciao<br clear="none">Gerhard<br clear="none"><br clear="none">DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:<br clear="none">"I think the problem, to be quite honest with you,<br clear="none">is that you have never actually known what the question is."<br clear="none"><br clear="none">====================================<br clear="none">Dr. Gerhard H. Fecher<br clear="none">Institut of Inorganic and Analytical Chemistry<br clear="none">Johannes Gutenberg - University<br clear="none">55099 Mainz<br clear="none">and<br clear="none">Max Planck Institute for Chemical Physics of Solids<br clear="none">01187 Dresden<br clear="none">________________________________________<div class="yqt1705344498" id="yqtfd11444"><br clear="none">Von: Wien [<a shape="rect" ymailto="mailto:wien-bounces@zeus.theochem.tuwien.ac.at" href="mailto:wien-bounces@zeus.theochem.tuwien.ac.at">wien-bounces@zeus.theochem.tuwien.ac.at</a>] im Auftrag von Jameela Fatheema [<a shape="rect" ymailto="mailto:j.fatheema96@yahoo.com" href="mailto:j.fatheema96@yahoo.com">j.fatheema96@yahoo.com</a>]<br clear="none">Gesendet: Montag, 17. Juli 2017 10:11<br clear="none">An: A. Mailing List for WIEN2k Users<br clear="none">Betreff: [Wien] symmetry problem for spontaneous polarization<br clear="none"><br clear="none">Dear all,<br clear="none"><br clear="none">I am running wien version 14 on ubuntu 16.<br clear="none"><br clear="none">The purpose of my calculations is to calculate the spontaneous polarization for Bi4Ti3O12 tetragonal structure.<br clear="none"><br clear="none">I have followed the steps provided by the wien2k UG and the notes that are available on wien2k site. The space group is I4/mmm which genertaes 16 symmetry operations for the structure. For the noncentrosymmetric polarization, i displace the titanium and oxygen atoms in the z-direction, about 0.005. this changes the symmetry to 8 and i get the space group as I4mm. After the total polarization for I4mm is obtained i do the steps as mentioned in the notes and tutorial available. The problem is how do i avoid this symmetry change because as much i understand the symmetry needs to remain the same. If i dont do the initialization for the centrosyymetric calculations it shows the ROTDEF error in dstart which is due to the symmetry difference.<br clear="none"><br clear="none">Should i make the displacement even more smaller?<br clear="none"><br clear="none">I will be very thankful for any advice.<br clear="none"><br clear="none">Regards<br clear="none">Jameela Fatheema<br clear="none">University of Peshawar.</div><br clear="none"><br clear="none"><br clear="none">_______________________________________________<br clear="none">Wien mailing list<br clear="none"><a shape="rect" ymailto="mailto:Wien@zeus.theochem.tuwien.ac.at" href="mailto:Wien@zeus.theochem.tuwien.ac.at">Wien@zeus.theochem.tuwien.ac.at</a><br clear="none"><a shape="rect" href="http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien" target="_blank">http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</a><br clear="none">SEARCH the MAILING-LIST at: <a shape="rect" href="http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html" target="_blank">http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html</a><div class="yqt1705344498" id="yqtfd99485"><br clear="none"></div></body></html></div></div></div></div></div></body></html>