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<p>Dear all, <br>
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<p>Let's say we want to optimize a configuration (and find the equilibrium lattice constant) but we don't know the optimal value of ecut (ecutrho) and/or k-points. My question is which one of the following procedure should be followed in order to find the converged
values and is more accurate? <br>
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<p>1. Do the vc-relax calculation for different values of ecut. Find the one that gives the converged value of total energy and the corresponding value of CELL_PARAMETER is the final lattice constant.
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<p> or<br>
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<p>2. Do scf calculation for different values of cutoff, choose the converged value and then do the vc-relax with that converged value of ecut and find the lattice constant. </p>
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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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