<html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div style="font-family: Helvetica, Arial, sans-serif; font-size: 16px;"><div>Dear Sir,</div><div><br></div><div>In one of the Phonopy exercise for SrTiO3, Peter Sir mentioned the "run_lapw -<g class="gr_ gr_30 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="30" data-gr-id="30">fc</g> 0.1" command to run scf for Phonopy generated structure files.</div><div><br></div><div>My query is: without <g class="gr_ gr_33 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar only-ins doubleReplace replaceWithoutSep" id="33" data-gr-id="33">min_lapw</g> switch, does "-fc0.1" switch will work? If it works then how it will affect the scf calculations?</div><div><br></div><div>If my case if SrTiO3 and I am getting three new structure files with Phonopy then do I need to do scf calculation</div><div><br></div><div>with "min_lapw -j "run_lapw -fc 0.1 ...." or simply with "run_lapw -fc 0.1"?</div><div><br></div><div><br></div><div>I see in case of SrTiO3 all three generated structure is having high atomic positions but in one my other case the newly generated structures are having some flexible positions (see below part of structure file) so I am not sure how to proceed for scf.</div><div><br></div><div><br></div><div>My doubt arises as I read a statement in Phonopy UG .Below is <g class="gr_ gr_190 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar only-ins doubleReplace replaceWithoutSep" id="190" data-gr-id="190">statement</g> which I am not getting well.</div><div> <br></div><div>"Note that supercells with displacements must not be relaxed in the force calculations because atomic forces induced by a small atomic displacement are what we need for phonon calculation."</div><div> <br></div><div>=== part of struct file =====</div><div><br></div><div>ATOM 9: X=0.24520000 Y=0.00000000 Z=0.00000000<br> MULT= 6 ISPLIT=-2<br>ATOM 9: X=0.75480000 Y=0.00000000 Z=0.00000000<br>ATOM 9: X=0.00000000 Y=0.24520000 Z=0.00000000<br>ATOM 9: X=0.00000000 Y=0.75480000 Z=0.00000000<br>ATOM 9: X=0.00000000 Y=0.00000000 Z=0.24520000<br>ATOM 9: X=0.00000000 Y=0.00000000 Z=0.75480000<br>I NPT= 781 R0=0.00001000 RMT= 2.5000 Z: 53.0<br>LOCAL ROT MATRIX: 0.0000000 0.0000000 1.0000000<br> 0.0000000 1.0000000 0.0000000<br> -1.0000000 0.0000000 0.0000000<br>ATOM 10: X=0.74520000 Y=0.50000000 Z=0.00000000<br> MULT= 6 ISPLIT=-2<br>ATOM 10: X=0.25480000 Y=0.50000000 Z=0.00000000<br>ATOM 10: X=0.50000000 Y=0.74520000 Z=0.00000000<br>ATOM 10: X=0.50000000 Y=0.25480000 Z=0.00000000<br>ATOM 10: X=0.50000000 Y=0.50000000 Z=0.24520000<br>ATOM 10: X=0.50000000 Y=0.50000000 Z=0.75480000<br>I NPT= 781 R0=0.00001000 RMT= 2.5000 Z: 53.0<br>LOCAL ROT MATRIX: 0.0000000 0.0000000 1.0000000<br> 0.0000000 1.0000000 0.0000000<br> -1.0000000 0.0000000 0.0000000<br>ATOM 11: X=0.74520000 Y=0.00000000 Z=0.50000000<br> MULT= 6 ISPLIT=-2<br>ATOM 11: X=0.25480000 Y=0.00000000 Z=0.50000000<br>ATOM 11: X=0.50000000 Y=0.24520000 Z=0.50000000<br>ATOM 11: X=0.50000000 Y=0.75480000 Z=0.50000000<br>ATOM 11: X=0.50000000 Y=0.00000000 Z=0.74520000<br>ATOM 11: X=0.50000000 Y=0.00000000 Z=0.25480000<br>I NPT= 781 R0=0.00001000 RMT= 2.5000 Z: 53.0<br>LOCAL ROT MATRIX: 0.0000000 0.0000000 1.0000000<br> 0.0000000 1.0000000 0.0000000<br> -1.0000000 0.0000000 0.0000000<br>ATOM 12: X=0.24520000 Y=0.50000000 Z=0.50000000<br> MULT= 6 ISPLIT=-2<br>ATOM 12: X=0.75480000 Y=0.50000000 Z=0.50000000<br>ATOM 12: X=0.00000000 Y=0.74520000 Z=0.50000000<br><br><div><br></div><div>As the phonon calculations are time demanding so I will start the calculations after getting a response from you!!!</div><div><br></div><div><br></div></div><div>Thanks in advance!!</div><div><br></div><div><br></div><div>Chin S.</div><div><br></div><div><br></div><div> <br></div><div><br></div></div></div></body></html>