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Hello QE community,</div>
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I am trying to study the material under uni-axial strain. I put the atomic coordinates in crystal coordinate and then apply the strain to the lattice vectors.</div>
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For example,</div>
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If S is my original (unstrained) lattice vectors:</div>
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array([[ 1.98619742 , 7.132231003, 0. ],</div>
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[-1.986197815, 7.132230891, 0. ],</div>
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[ 0. , 0. , 13.586526936]])</div>
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Then applying 1% strain (tensile) to S along x-axis, would result</div>
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Strained_lattice=array([[ 2.0060593942, 7.132231003 , 0. ],</div>
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[-2.0060597931, 7.132230891 , 0. ],</div>
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[ 0. , 0. , 13.586526936 ]])</div>
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After this lattice determination, I want to relax (or vc-relax) structure in such a way that it respects Poisson's ratio (keeping constant Poisson's ratio).</div>
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My question is:</div>
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Do I just "relax" the structure? or</div>
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"vc-relax" with cell_dofree=<tt>
<div>'fixa' </div>
</tt></div>
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Or which cell_dofree would be appropriate?</div>
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Thank you.</div>
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Best</div>
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Rijan Karkee</div>
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