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<p class="MsoNormal">Hello,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My question is how to calculate scf energy of water molecule in large cell size of 12 angstrom. The energy cutoff is at 160 ry. The dft method I used is scan. Mixing_beta=0.1 and diagonalization = 'cg’. When the cell size is beyond 16
bohr the program reported ‘too many bands are not converged and estimated scf accuracy is too large.
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m wondering if there is any other options I can add in my input to make scf energy converged for water molecule in large box?</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal">Jing</p>
<p class="MsoNormal">University of delaware</p>
<p class="MsoNormal"><o:p></o:p></p>
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