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<p class="MsoNormal">Hello everyone,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">To study diffusion barrier using NEB, to prepare the initial and final states, I am performing “relax” calculations with interstitials inserted into a vc-relaxed pure bcc W cell structure.<o:p></o:p></p>
<p class="MsoNormal">I have used k-points, cut-offs and cells size after verifying the convergence, but with interstitial added, I am having issues.<o:p></o:p></p>
<p class="MsoNormal">I have tried “mv” and “mp” smearing options, and I am USPP pseuodopotentials. With pure cell, convergence is usually between 16 to 40 iterations.<o:p></o:p></p>
<p class="MsoNormal">I tried the possibility of W being magnetic, and spin polarization option as well.<o:p></o:p></p>
<p class="MsoNormal">With an interstitial atom added, it doesn’t converge well. I have retried with finer k-point grids as well, but no luck.<o:p></o:p></p>
<p class="MsoNormal">With the interstitial setup, I realize that the cell has odd number of valence electrons. Does the odd number of valence electrons in a cell matter?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have searched through the mailing list archives, but can’t seem to find any related posts on treating interstitials.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have attached the input and output files, if someone could see what I am missing.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="background:white"><span style="color:black">Regards,<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="color:black">Tejas R<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="color:black">PhD Student</span><o:p></o:p></p>
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