<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Here, a list of the ibrav values that you can choose<div class=""><a href="https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm200" class="">https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm200</a></div><div class=""><br class=""></div><div class="">It seems that you have a simple orthorhombic lattice, that should correspond to ibrav = 8.</div><div class="">Than you can specify the variables</div><div class="">a</div><div class="">b</div><div class="">c</div><div class="">as crystal axes lengths in Angstrom units.</div><div class=""><br class=""></div><div class="">Giovanni</div><div class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 18 Mar 2021, at 10:03, Offermans Willem <<a href="mailto:willem.offermans@vito.be" class="">willem.offermans@vito.be</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><div class=""><br class=""></div><div class="">Dear Quantum Espresso friends,</div><div class=""><br class=""></div><div class="">In most of my calculations, I’m dealing with metallic slabs, representing</div><div class="">surfaces, derived from fcc metals, such as (221) or (533).</div><div class=""><br class=""></div><div class="">In these calculations, I’m dealing with structures with symmetry.</div><div class="">The single symmetry element is an inversion center. S_2 is the Schönfließ symbol,</div><div class="">if I recall correctly. </div><div class=""><br class=""></div><div class="">In the output file of pw.x, I encounter the following note:</div><div class=""><br class=""></div><div class=""><snip></div><div class="">...</div><div class=""> Message from routine setup:</div><div class=""> using ibrav=0 with symmetry is DISCOURAGED, use correct ibrav instead</div></div><div class="">…</div><div class=""></snip></div><div class=""><br class=""></div><div class=""><div class="">The unitcell is defined as:</div><div class=""><br class=""></div><div class=""><snip></div><div class="">...</div><div class=""> celldm(1)= 10.627880 celldm(2)= 0.000000 celldm(3)= 0.000000</div><div class=""> celldm(4)= 0.000000 celldm(5)= 0.000000 celldm(6)= 0.000000</div><div class=""><br class=""></div><div class=""> crystal axes: (cart. coord. in units of alat)</div><div class=""> a(1) = ( 1.000000 0.000000 0.000000 ) </div><div class=""> a(2) = ( 0.000000 1.500000 0.000000 ) </div><div class=""> a(3) = ( 0.000000 0.000000 4.596194 ) </div></div><div class="">…</div><div class=""></snip></div><div class=""><br class=""></div><div class="">I would like to follow the advice to use the correct ibrav, but I need some help</div><div class="">to determine the correct ibrav. </div><div class=""><br class=""></div><div class="">Can someone help me to determine the correct Ibrav?</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><br class=""><div class="">
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letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">Met vriendelijke groeten,</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">Mit freundlichen Grüßen,</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">With kind regards,</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; 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font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">Researcher Electrocatalysis SCT</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">VITO NV | Boeretang 200 | 2400 Mol</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; 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<div style="text-align: start; text-indent: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><span style="color: rgb(0, 0, 0); letter-spacing: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" 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=""><a href="mailto:giovanni.cantele@spin.cnr.it" class="">e-mail: giovanni.cantele@spin.cnr.it</a><br class="">Phone: +39 081 676910<br class="">Skype contact: giocan74<br class=""><br class="">ResearcherID: http://www.researcherid.com/rid/A-1951-2009<br class="">Web page:<span class="Apple-converted-space"> </span></span><a href="https://sites.google.com/view/giovanni-cantele/home" class="">https://sites.google.com/view/giovanni-cantele/home</a></div>
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