<div dir="ltr">It's impossible for space group #194 to have 15 atoms of one species and 1 atom of another species -- there aren't any Wyckoff positions in P6_3/mmc that contain only one point.<div><br></div><div>What you've done eliminates the inversion operation, which changes #194 to #187.</div><div><br></div><div>Take a look at both space groups in the International Tables or <a href="http://www.cryst.ehu.es/cryst/get_wp.html">http://www.cryst.ehu.es/cryst/get_wp.html</a> and you'll see this.</div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Feb 9, 2018 at 4:48 AM, Krishnendu Mukherjee <span dir="ltr"><<a href="mailto:krishnendu.mukherjee789@gmail.com" target="_blank">krishnendu.mukherjee789@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><div><br></div>Dear Experts,<br><br></div> I have created a Zr15Nb1 cell containing 15 Zr atoms and 1 Nb atom using the space group P 63/m m c, (space group number 194).<br><br></div> But, when I try to calculate the elastic constant of it using the thermo_pw, I find, pwscf recognizes wrong space group (No. 187). Please find below my input:<br><br></div></div></blockquote></div><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><span><div dir="ltr" style="margin-left:0pt"><span><div dir="ltr" style="margin-left:0pt"><table style="border:none;border-collapse:collapse"><colgroup><col width="73"><col width="240"></colgroup><tbody><tr style="height:0px"><td style="border-left:solid #ffffff 1px;border-right:solid #ffffff 1px;border-bottom:solid #ffffff 1px;border-top:solid #ffffff 1px;vertical-align:top;padding:7px 7px 7px 7px"><br><img src="https://lh4.googleusercontent.com/cWahY61df5ZQz3h0L--aoIVBK4j_u5sWfktSfeRgcbi3bi_PKu-Vtt8OPXlJEEX7_J8UVfbP6EYLXroCVHzqegMVgjl4KD3yBpnJZp0zwht66TTfYleiGnAbqPTj7TEwVxNRrdA6" width="57" height="80" style="border:none" alt="USNA_Gold_Seal.png"></td><td style="border-left:solid #ffffff 1px;border-right:solid #ffffff 1px;border-bottom:solid #ffffff 1px;border-top:solid #ffffff 1px;vertical-align:top;padding:7px 7px 7px 7px"><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Michael J. Mehl, Ph.D.     </span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Kinnear Chair in Physics</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">The United States Naval Academy</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Mail Stop 9C</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">572 Holloway Road</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Chauvenet Hall 257</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Annapolis MD 21402</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">(410)293-6685</span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent"><a href="mailto:mmehl@usna.edu" target="_blank">mmehl@usna.edu</a></span></p><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt"><a href="http://aflow.org/CrystalDatabase/" target="_blank">Library of Crystallographic Prototypes</a></p></td></tr></tbody></table></div></span></div></span></div><span><br></span></div></div></div></div></div></div></div>
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