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<DIV><FONT face=Arial size=2>dear list-users,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm trying to run vc-relax or vc-md
calculation on a mineral using pw.x, and my purpose is to</FONT></DIV>
<DIV><FONT face=Arial size=2>investigate what kind of structrues it would evolve
into upon applying a serise of pressures.</FONT></DIV>
<DIV><FONT face=Arial size=2>I know that because of finite-size effect the
transition pressure determined this way is </FONT></DIV>
<DIV><FONT face=Arial size=2>meaningless. I just want to get the possible
structures and then use total energy calculations</FONT></DIV>
<DIV><FONT face=Arial size=2>for different phases to determine the transition
pressures at 0K. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>But firstly I need to make clear the
</FONT><FONT face=Arial size=2>following questions:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>(1) I think, for my purpose, I may need to use
vc-relax, but what's the differences between </FONT></DIV>
<DIV><FONT face=Arial size=2> vc-relax and vc-md method in the
implementation because the PR dynamics is the same</FONT></DIV>
<DIV><FONT face=Arial size=2> for both methods (am I wrong)?</FONT></DIV>
<DIV><FONT face=Arial size=2>(2) Should I always set ibrav = 14 (trilinic
system) for variable cell calculation?</FONT></DIV>
<DIV><FONT face=Arial size=2>(3) Although in the manual INPUT_PW, tempw in
&ION, press, wmass in &CELL are said to </FONT></DIV>
<DIV><FONT face=Arial size=2> be used in MD runs, they also can
be </FONT><FONT face=Arial size=2>used in vc-relax runs (for controlling
temperature), right?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks!</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Huiqun Zhou</FONT></DIV></BODY></HTML>