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<p>Thank you for your reply. After doing vc-relax, how do you find the final lattice constant in the output file?
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<p>Best,<br>
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<p>Amir M. Mofrad<span> <br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> pw_forum-bounces@pwscf.org <pw_forum-bounces@pwscf.org> on behalf of Максим Арсентьев <ars21031960@gmail.com><br>
<b>Sent:</b> Tuesday, August 2, 2016 2:13:47 AM<br>
<b>To:</b> PWSCF Forum<br>
<b>Subject:</b> Re: [Pw_forum] Equilibrium Lattice Constant</font>
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<div dir="ltr">For me vc-relax is practically more convenient: you do not need make additional operations</div>
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<div class="gmail_quote">2016-08-02 2:07 GMT+04:00 Mofrad, Amir Mehdi (MU-Student)
<span dir="ltr"><<a href="mailto:amzf5@mail.missouri.edu" target="_blank">amzf5@mail.missouri.edu</a>></span>:<br>
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<p>Dear all, <br>
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<p>Based on the materials available on the internet, I have realized that apparently there are two ways to find the lattice constant:
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<p>1. After finding the the converged cutoff from scf calculations, use that value for different lattice parameters and find the corresponding minimum energy.</p>
<p>2. Use "vc-relax" for different values of cutoff and find the lattice constant that gives you the minimum energy.
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<p>Which one is more accurate? And, is there more than that to do find the lattice parameter?
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<p>P.S. I want to find the lattice constant of a material consisting only of Si and O.<br>
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<p>Any help would be thoroughly appreciated. <br>
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<p>Best,<br>
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<p>Amir M. Mofrad<span> <br>
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<div>Best wishes,</div>
<div>Maxim Arsent'ev, Ph.D. (Chemistry)</div>
<div>Laboratory of research of nanostructures</div>
<div>Institute of Silicate Chemistry of RAS</div>
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