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Dear all,<div><br></div><div>I am using the EPW package in conjunction with QE to calculate electron phonon coefficients for systems. The "scf", "ph" and "nscf" run quite smoothly; however when I execute the last step which is using the "epw.x" command I get the error:</div><div><br></div><div>"Q(r) pseudized with 0 coefficients</div><div><br></div><div>     EPW          :     6.72s CPU time,   17.23s wall time</div><div><br></div><div>     EPW          :    14.08s CPU time,   28.02s wall time</div><div><br></div><div>     EPW          :    14.08s CPU time,   28.02s wall time</div><div><br></div><div><br></div><div> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%</div><div>     from setphases_wrap : error #         1</div><div>     only one proc per pool</div><div> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%"</div><div><br></div><div>"The parallel execution is such that:</div><div><br></div><div><div>Program EPW       v.2.3.5  starts ...</div><div>     Today is 12Nov2012 at  2:27:22</div><div><br></div><div>     Parallel version (MPI)</div><div><br></div><div>     Number of processors in use:      16</div><div>     R & G space division:  proc/pool =   16"</div></div><div><br></div><div>However when I reduce the number to 8 processors (that is 1 node on the cluster I am working on), I get another error from davcio:</div><div><br></div><div>"<span style="font-size: 10pt;">%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%</span></div><div>     from davcio : error #        20</div><div>     error while reading from file</div><div> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%</div><div>"</div><div><br></div><div>Mind you that the previous scf , nscf and ph steps were done with 16 processors. Could that be the error? Would repeating everything with 8 processors work?</div><div><br></div><div>Thanks in advance</div><div><br></div><div>Elias ALbert</div><div>Uniiversity of Derby</div><div>DE12 4ER</div><div>UK</div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div>                                           </div></body>
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