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Dear QE users,</div>
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I am trying to understand the relation between the electron-phonon matrix elements stored in elph.#iq.#irr.xml and the values printed by ph.x using electron_phonon='prt'.</div>
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QE version: 7.5</div>
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q-point: Gamma</div>
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>From elph.1.3.xml, I obtain:</div>
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7.891896321880264E-03 -3.187338227203423E-16</div>
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However, the value printed by ph.x for the same Gamma point is:</div>
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0.5937940455E-01 meV</div>
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I have checked that:</div>
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- both correspond to the Gamma point</div>
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- the same perturbation/mode is used</div>
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- the band indices are consistent</div>
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My question is:</div>
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what transformations are applied between the raw matrix elements in elph.xml and the printed values in ph.x?</div>
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Can the printed value be reconstructed directly from the XML data?</div>
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In particular, I see many k-points stored in the XML file, while the output file only provides the value of g at the Gamma point when setting kx=0, ky=0, kz=0. How should the matrix elements at other k-points be interpreted or used?</div>
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Thank you very much for your help.</div>
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Best regards,</div>
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Qi</div>
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