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<DIV><FONT face=Verdana color=#0000ff size=2>Dear Paolo Giannozzi,</FONT></DIV>
<DIV><FONT face=Verdana color=#0000ff size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=Verdana color=#0000ff size=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
Thank you for your kindly reply, the information about wyckoff position is 
really helpful. You mean the point group might not be found by the Q-E with the 
right label, So we could disregard the label found in the output file, the 
program should give the right results as long as the atomic postion was created 
correctly under the specific point group. By the way,URL &nbsp;<A 
href="http://cst-www.nrl.navy.mil/lattice/struk/LiNbO3f.html">http://cst-www.nrl.navy.mil/lattice/struk/LiNbO3f.html</A>&nbsp;could 
not be connected. Thank you again.</FONT></DIV>
<DIV><FONT face=Verdana color=#0000ff size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=Verdana color=#0000ff size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=Verdana color=#0000ff size=2>&nbsp;Best regards</FONT></DIV>
<DIV><FONT face=Verdana color=#0000ff size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=Verdana color=#0000ff size=2>Hongkien Feng</FONT></DIV>
<DIV align=left>
<DIV align=left><FONT face=Verdana size=2>
<HR style="WIDTH: 122px; HEIGHT: 2px" SIZE=2>
</FONT></DIV>
<DIV><FONT color=#c0c0c0><FONT face=Verdana size=2>fenghongjian</FONT></DIV>
<DIV><FONT face=Verdana size=2>2007-08-03</FONT></FONT></DIV></DIV>
<DIV><FONT face=Verdana size=2>
<HR>
</FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2><STRONG>发件人:</STRONG> Paolo 
Giannozzi</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2><STRONG>发送时间:</STRONG> 
2007-08-03&nbsp;17:39:42</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2><STRONG>收件人:</STRONG> PWSCF 
Forum</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2><STRONG>抄送:</STRONG> </FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2><STRONG>主题:</STRONG> Re: [Pw_forum] BiFeO3 
problem</FONT></FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=Verdana size=2>
<DIV>&nbsp;</DIV>
<DIV>On&nbsp;Aug&nbsp;3,&nbsp;2007,&nbsp;at&nbsp;10:15&nbsp;,&nbsp;Xunlei&nbsp;Ding&nbsp;wrote:</DIV>
<DIV>&nbsp;</DIV>
<DIV>&gt;&nbsp;Another&nbsp;question&nbsp;is:&nbsp;whether&nbsp;R3c&nbsp;symmetry&nbsp;is&nbsp;included&nbsp;in&nbsp;PWSCF,</DIV>
<DIV>&gt;&nbsp;or&nbsp;whether&nbsp;"c"&nbsp;can&nbsp;be&nbsp;recognized&nbsp;by&nbsp;PWSCF.</DIV>
<DIV>&nbsp;</DIV>
<DIV>ALL&nbsp;point&nbsp;symmetries&nbsp;that&nbsp;are&nbsp;relevant&nbsp;for&nbsp;periodic&nbsp;systems</DIV>
<DIV>are&nbsp;included&nbsp;in&nbsp;PWscf.&nbsp;PWscf&nbsp;may&nbsp;not&nbsp;be&nbsp;able&nbsp;to&nbsp;recognize</DIV>
<DIV>a&nbsp;given&nbsp;point&nbsp;group&nbsp;and&nbsp;to&nbsp;assign&nbsp;the&nbsp;correct&nbsp;label,&nbsp;but&nbsp;this</DIV>
<DIV>has&nbsp;no&nbsp;effect&nbsp;on&nbsp;the&nbsp;final&nbsp;results.&nbsp;PWscf&nbsp;will&nbsp;find&nbsp;all&nbsp;point</DIV>
<DIV>symmetries&nbsp;that&nbsp;are&nbsp;there.&nbsp;If&nbsp;it&nbsp;doesn't&nbsp;find&nbsp;them,&nbsp;it&nbsp;is</DIV>
<DIV>because&nbsp;they&nbsp;are&nbsp;not&nbsp;there.</DIV>
<DIV>&nbsp;</DIV>
<DIV>BiFeO3&nbsp;should&nbsp;have&nbsp;the&nbsp;same&nbsp;structure&nbsp;as&nbsp;LiNbO3:</DIV>
<DIV><A 
href="http://cst-www.nrl.navy.mil/lattice/struk/LiNbO3f.html">http://cst-www.nrl.navy.mil/lattice/struk/LiNbO3f.html</A></DIV>
<DIV>&nbsp;</DIV>
<DIV>Paolo</DIV>
<DIV>---</DIV>
<DIV>Paolo&nbsp;Giannozzi,&nbsp;Democritos&nbsp;and&nbsp;University&nbsp;of&nbsp;Udine,&nbsp;Italy</DIV>
<DIV>&nbsp;</DIV>
<DIV>&nbsp;</DIV>
<DIV>_______________________________________________</DIV>
<DIV>Pw_forum&nbsp;mailing&nbsp;list</DIV>
<DIV>Pw_forum@pwscf.org</DIV>
<DIV><A 
href="http://www.democritos.it/mailman/listinfo/pw_forum">http://www.democritos.it/mailman/listinfo/pw_forum</A></DIV></FONT></DIV></BODY></HTML>