<div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif;font-size:small"><div class="gmail_default">Dear Shuai:</div><div class="gmail_default"><br></div><div class="gmail_default">I'm also a new learner.</div>
<div class="gmail_default"><br></div><div class="gmail_default">As for your first question, my experience is 'relax' is not equal to 'vc-relax'.</div><div class="gmail_default"><br></div><div class="gmail_default">
For short, 'relax' only change the atomic position, while 'vc-relax' has a variable unit cell as well as variable position.</div><div class="gmail_default"><br></div><div class="gmail_default">So if you <span style="font-family:arial,sans-serif;font-size:12.800000190734863px">do scf calculations by modifying the lattice constant and obtain the lattice constant with the lowest energy, in my opinion, vc-relax may be get similar result while the initial lattice constant is closed to the real one.</span></div>
<div class="gmail_default"><span style="font-family:arial,sans-serif;font-size:12.800000190734863px"><br></span></div><div class="gmail_default"><span style="font-family:arial,sans-serif;font-size:12.800000190734863px">Rds.</span></div>
<div><span style="font-family:arial,sans-serif;font-size:12.800000190734863px"><br></span></div></div><div class="gmail_extra"><br clear="all"><div><div dir="ltr"><div><i>————</i><br></div><div><i><br></i></div><div><font face="georgia, serif">徐健 Jian XU</font></div>
<div><font face="georgia, serif"><br></font><div><font face="georgia, serif">Dr. Eng.<br></font><div><font face="georgia, serif">Department of Metallurgical Engineering<br></font><div><font face="georgia, serif">College of Materials Science and Engineering<br>
</font><span style="font-family:georgia,serif">Faculty of Engineering, </span><font face="georgia, serif">Chongqing University<br><div class="gmail_default" style="font-family:georgia,serif;font-size:small;display:inline">
<br></div></font></div></div></div></div></div></div>
<br><br><div class="gmail_quote">On Sun, Jun 1, 2014 at 12:22 PM, Shuai <span dir="ltr"><<a href="mailto:zhao-shuai@edu.life.kyutech.ac.jp" target="_blank">zhao-shuai@edu.life.kyutech.ac.jp</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Dear QE users,<br>
<br>
I am a new learner and I have two questions about the relax/vc-relax
calculation.<br>
<br>
The first is that if I do scf calculations by modifying the lattice
constant and I could obtain the lattice constant with the lowest
energy. And then on this basis if I do a relax calculation (not
vc-relax), does its work equal to that of vc-relax?<br>
<br>
The second one is about the vc-relax calculation. After got the
vc-relax result, I could find the new cell_parameters and atomic
positions from the <i>vc-relax.out</i>. Thus do I need to set the
new cell_parameters and atomic positions as the new parameters in
the file of <i><a href="http://nscf.in" target="_blank">nscf.in</a></i>? or maybe the nscf calculation can read
the cell_parameters and atomic positions automatically from the
vc-relax.out?<br>
<br>
Thanks in advance.<br>
<br>
Best regards,<br>
<br>
Shuai<br>
<br>
--<br>
<div style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:14px;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255)">
<b>Graduate School of Life
Science and Systems Engineering</b></div>
<div style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:14px;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;background-color:rgb(255,255,255)">
<b>Kyushu Institute of
Technolog, Japan</b></div>
</div>
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