<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On 25 May 2017, at 12:08, <a href="mailto:aprateek@iisermohali.ac.in" class="">aprateek@iisermohali.ac.in</a> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Hi,<br class="">I am beginner in using Quantum Espresso. I am giving coordinates of one<br class="">atom (Si 0.0 0.0 0.0) in angstrom/crystal.<br class="">With ibrav=1 it forms Simple Cubic<br class="">With ibrav=2 it forms Face Centred Cubic<br class="">With ibrav=3 it forms Body Centred Cubic<br class="">and with ibrav=1 and<br class="">Si 0.0 0.0 0.0<br class="">Si 5.0 5.0 0.0<br class="">Si 5.0 0.0 5.0<br class="">Si 0.0 5.0 5.0<br class=""><br class="">it forms face centred lattice. I would like to know the algorithim which<br class="">Xcrysden follows during visualization?<br class=""><br class="">what if I want to control the no of atoms 3 or 4 in a Unit cell. ?<br class=""><br class="">_______________________________________________<br class="">Pw_forum mailing list<br class=""><a href="mailto:Pw_forum@pwscf.org" class="">Pw_forum@pwscf.org</a><br class="">http://pwscf.org/mailman/listinfo/pw_forum<br class=""></div></div></blockquote></div><div class=""><br class=""></div><div class=""><br class=""></div>Maybe in the last for positions you meant 0.5, not 5.0. By the way, there is no algorithm, but simply at each ibrav<div class="">corresponds a lattice. For example ibrav=1 corresponds to a simple cubic lattice. The list of ibrav <-> lattice</div><div class="">correspondences can be found here:</div><div class=""><a href="http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#idm140629872541472" class="">http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#idm140629872541472</a></div><div class=""><br class=""></div><div class="">It is true that the lattice sites of a face centered lattice can be described, besides using the obvious face centred lattice,</div><div class="">with a simple cubic lattice with four atoms in the unit cell.</div><div class=""><br class=""></div><div class="">I suggest you to read the relevant documentation/tutorials that are available.</div><div class=""><br class=""></div><div class="">Giovanni</div><div class=""><br class=""><div class="">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">-- <br class=""><br class="">Giovanni Cantele, PhD<br class="">CNR-SPIN<br class="">c/o Dipartimento di Fisica<br class="">Universita' di Napoli "Federico II"<br class="">Complesso Universitario M. S. Angelo - Ed. 6<br class="">Via Cintia, I-80126, Napoli, Italy<br class="">e-mail: <a href="mailto:giovanni.cantele@spin.cnr.it" class="">giovanni.cantele@spin.cnr.it</a><br class="">Phone: +39 081 676910<br class="">Skype contact: giocan74<br class=""><br class="">ResearcherID: <a href="http://www.researcherid.com/rid/A-1951-2009" class="">http://www.researcherid.com/rid/A-1951-2009</a><br class="">Web page: <a href="http://people.fisica.unina.it/~cantele" class="">http://people.fisica.unina.it/~cantele</a><br class=""></div>
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