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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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