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<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><FONT
face=Calibri>Hi, folks!</FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN
lang=EN-US></SPAN> </P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><FONT
face=Calibri>I downloaded a XRD result of a crystal from CCDC. The cif file
shows it has a space group of P2_12_12_1. I found after geometry optimization in
PWscf, the symmetry has been reduced into P2_1. Is there any option or method to
keep the symmetry invariant during geometry optimization in
PWscf?</FONT></SPAN></P>
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face=Calibri> </FONT></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><FONT
face=Calibri>Thanks a lot in advance!</FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><o:p><FONT
face=Calibri> </FONT></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US><FONT
face=Calibri>Yin</FONT></SPAN></P><!--EndFragment--></DIV></SPAN></SPAN></BODY></HTML>