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<div class="">Dear Quantum Espresso Friends,</div>
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<div class="">I’m relatively new to Quantum Espresso, so please excuse my ignorance.</div>
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<div class="">I have performed a series of geometry optimisations with increased accuracy. The series consists of the same system with originally S2 Symmetry (inversion center).</div>
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<div class="">During the optimisations, the system loses its S2 symmetry. This is not logical to my opinion. If I put a system with S2 symmetry in and perform a geometry optimisation, how can this symmetry disappear.</div>
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<div class="">Can someone point out what the reason of this might be?</div>
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<div class="">The first input file is:</div>
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<div class=""><snip></div>
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<div class="">&CONTROL</div>
<div class=""> tprnfor = .true.</div>
<div class=""> pseudo_dir = ‘./'</div>
<div class="">/</div>
<div class="">&SYSTEM</div>
<div class=""> ecutwfc = 25</div>
<div class=""> ecutrho = 100</div>
<div class=""> occupations = 'smearing'</div>
<div class=""> degauss = 1e-05</div>
<div class=""> ntyp = 2</div>
<div class=""> nat = 22</div>
<div class=""> ibrav = 0</div>
<div class="">/</div>
<div class="">&ELECTRONS</div>
<div class=""> conv_thr = 0.0001</div>
<div class="">/</div>
<div class="">&IONS</div>
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<div class="">&CELL</div>
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<div class="">ATOMIC_SPECIES</div>
<div class="">Pd 106.42 Pd.pbe-n-kjpaw_psl.0.2.2.UPF</div>
<div class="">O 15.999 O.pbe-n-kjpaw_psl.0.1.UPF</div>
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<div class="">K_POINTS automatic</div>
<div class="">5 5 1 0 0 0</div>
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<div class="">CELL_PARAMETERS angstrom</div>
<div class="">5.58600000000000 0.00000000000000 0.00000000000000</div>
<div class="">2.79300000000000 4.83761790553987 0.00000000000000</div>
<div class="">0.00000000000000 0.00000000000000 18.24379960424911</div>
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<div class="">ATOMIC_POSITIONS angstrom</div>
<div class="">Pd -0.0335794144 -0.0194045402 4.5434337591 </div>
<div class="">Pd 2.8214009258 -0.0184323442 4.5449980368 </div>
<div class="">Pd 1.3950257690 2.4527388071 4.5453108255 </div>
<div class="">Pd 4.1923282610 2.4205853877 4.6209194390 </div>
<div class="">Pd 1.4011208738 0.8092502291 6.8896667876 </div>
<div class="">Pd 4.1905782218 0.8048960573 6.8423310749 </div>
<div class="">Pd 2.7922495046 3.2267803491 6.8425771368 </div>
<div class="">Pd 5.5950417579 3.2300318834 6.8469560609 </div>
<div class="">Pd 2.7967155055 1.6150488112 9.1443519061 </div>
<div class="">Pd 5.5836118435 1.6172941601 9.1216875069 </div>
<div class="">Pd 4.1918881565 4.0265933964 9.1221120974 </div>
<div class="">Pd 6.9787844945 4.0288387452 9.0994476982 </div>
<div class="">Pd 4.1804582421 2.4138556731 11.3968435434 </div>
<div class="">Pd 6.9832504954 2.4171072073 11.4012224674 </div>
<div class="">Pd 5.5849217782 4.8389914992 11.4014685293 </div>
<div class="">Pd 8.3743791262 4.8346373274 11.3541328167 </div>
<div class="">Pd 5.5831717390 3.2233021688 13.6228801653 </div>
<div class="">Pd 8.3804742310 3.1911487494 13.6984887788 </div>
<div class="">Pd 6.9540990742 5.6623199007 13.6988015674 </div>
<div class="">Pd 9.8090794144 5.6632920967 13.7003658451 </div>
<div class="">O 1.3998448637 0.8084019389 3.3512841183 </div>
<div class="">O 8.3756551363 4.8354856176 14.8925154859 </div>
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<div class="">In the first output file:</div>
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<div class="">...</div>
<div class="">2 Sym. Ops., with inversion, found ( 1 have fractional translation)</div>
<div class="">…</div>
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Met vriendelijke groeten,</div>
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Mit freundlichen Grüßen,</div>
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Willem Offermans</div>
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Researcher Electrocatalysis SCT</div>
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VITO NV | Boeretang 200 | 2400 Mol</div>
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Phone:+32(0)14335263 Mobile:+32(0)492182073 </div>
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<a href="mailto:Willem.Offermans@Vito.be" class="">Willem.Offermans@Vito.be</a></div>
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<font color="#999999" size="-2" face="Arial, Helvetica, sans-serif">Indien u VITO Mol bezoekt, hou aub er dan rekening mee dat de hoofdingang voortaan enkel bereikbaar is vanuit de richting Dessel-Retie, niet vanuit richting Mol, zie
<a href="http://www.vito.be/route">vito.be/route.</a><br>
If you plan to visit VITO at Mol, then please note that the main entrance can only be reached coming from Dessel-Retie and no longer coming from Mol, see
<a href="http://www.vito.be/en/contact/locations">vito.be/en/contact/locations.</a><br>
</font><font color="#999999" size="-2" face="Arial, Helvetica, sans-serif">VITO Disclaimer:
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