<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=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 13 Feb 2019, at 09:50, Offermans Willem <<a href="mailto:willem.offermans@vito.be" class="">willem.offermans@vito.be</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
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<div class="">Dear Quantum Espresso friends,</div></div></div></blockquote><div><br class=""></div>Dear Wilem:</div><div><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">
<div class="">I made a mistake in my previous e-mail.</div>
<div class="">The atom coordinates are not in Angstrom but in Bohr.</div></div></div></blockquote><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">
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<div class="">I have corrected this in my calculations, but still no symmetry found.</div></div></div></blockquote><div><br class=""></div>I would be surprised if you found the contrary. I cannot imagine that the point symmetry of any system could depend on units: do you?</div><div><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">
<div class="">$ grep "ymmetr" pd_?/PW.out </div>
<div class="">pd_1/PW.out: No symmetry found</div>
<div class="">pd_2/PW.out: No symmetry found</div>
<div class="">pd_3/PW.out: No symmetry found</div>
<div class="">pd_4/PW.out: No symmetry found</div>
<div class="">pd_5/PW.out: No symmetry found</div>
<div class="">pd_6/PW.out: No symmetry found</div>
<div class="">pd_7/PW.out: No symmetry found</div>
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<div class="">So the question remains. What is the reason that the symmetry cannot be detected?</div>
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<div class="">As an extra check I have made a scf calculation on the last image.</div>
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<div class="">$ grep "Sym. Ops." pd.out </div>
<div class=""> 2 Sym. Ops., with inversion, found ( 1 have fractional translation)</div>
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<div class="">So pw.x can find the symmetry whereas neb.x cannot!</div></div></div></blockquote><div><br class=""></div>Just guessing: maybe for some reasons neb restricts its search to pure rotations (no fractional translations involved). Also, I have the impression that inversion symmetry does not help save any computer time, because in practice it has the same effects as time-reversal symmetry, which always holds.</div><div><br class=""></div><div>Just my worthless 5 cents …</div><div>SB</div><div><br class=""></div><br class=""><div class="">
<span class="Apple-style-span" style="border-collapse: separate; font-variant-ligatures: normal; font-variant-position: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; line-height: normal; orphans: 2; text-indent: 0px; widows: 2; border-spacing: 0px;"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><div class=""><span class="Apple-style-span" style="border-collapse: separate; font-variant-ligatures: normal; font-variant-position: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; line-height: normal; orphans: 2; text-indent: 0px; widows: 2; border-spacing: 0px;"><span class="Apple-style-span" style="border-collapse: separate; font-variant-ligatures: normal; font-variant-position: normal; font-variant-numeric: normal; font-variant-alternates: normal; font-variant-east-asian: normal; line-height: normal; orphans: 2; text-indent: 0px; widows: 2; border-spacing: 0px;"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><span style="font-size: 12px;" class="">— </span></div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><div style="margin: 0px;" class=""><font class="Apple-style-span"><span style="font-size: 12px;" class="">Stefano Baroni - Trieste — </span><a href="http://stefano.baroni.me" style="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-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-stroke-width: 0px;" class="">http://stefano.baroni.me</a><span style="font-size: 12px;" class=""> </span></font></div></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-stroke-width: 0px;" class=""><br class=""></div></div></div></div></div></div></div></span></span></div></div></div></span><br class="Apple-interchange-newline"><br class="Apple-interchange-newline">
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