<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN" "http://www.w3.org/TR/REC-html40/strict.dtd"><html><head><meta name="qrichtext" content="1" /><style type="text/css">p, li { white-space: pre-wrap; }</style></head><body style=" font-family:'Sans Serif'; font-size:14pt; font-weight:400; font-style:normal;">On 2009/03/22 Sunday 09:58:46 孙阳 wrote:<br>
> By looking at the CELL_PARAMETER, we see that the crystal loose the<br>
> symmetry of orthorhombic but simply triclinic.<br>
><br>
> Can we do VC-relax by keeping the previous symmetry?<br>
<span style=" font-size:12pt;">maybe the variable '</span><span style=" font-size:12pt;">cell_dofree' </span><span style=" font-size:12pt;"> in namelist 'CELL' is something your are looking for. However, this option is not a robust enough, and it is not recommend to use it.</span><br>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-size:12pt;"><br></p><span style=" font-size:12pt;">you can try to restart with the cell parameters you got and ignore the </span><span style=" font-family:'Bitstream Vera Sans'; font-size:12pt;">divergence of </span><span style=" font-size:12pt;"> symmetry. </span><br>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-size:12pt;"><br></p><span style=" font-size:12pt;">>CELL_PARAMETERS (alat)</span><br>
<span style=" font-size:12pt;">> 0.496579626 0.283698921 -0.001038829</span><br>
<span style=" font-size:12pt;">> -0.496579626 0.283698921 -0.001038829</span><br>
<span style=" font-size:12pt;">> 0.000000000 -0.002166536 0.600253523</span><br>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-size:12pt;"><br></p><span style=" font-size:12pt;">CELL_PARAMETERS (alat)</span><br>
<span style=" font-size:12pt;"> 0.496579626 0.283698921 [0]</span><br>
<span style=" font-size:12pt;"> -0.496579626 0.283698921 [0]</span><br>
<span style=" font-size:12pt;"> 0.000000000 [0] 0.600253523</span><br>
<p style="-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0; font-size:12pt;"><br></p><span style=" font-size:12pt;">this is only a suggestion, I didn't try it out, so may be incorrect.</span></p></body></html>